Sample records for fluorophotometry

  1. Corneal permeability changes in dry eye disease: an observational study.

    PubMed

    Fujitani, Kenji; Gadaria, Neha; Lee, Kyu-In; Barry, Brendan; Asbell, Penny

    2016-05-13

    Diagnostic tests for dry eye disease (DED), including ocular surface disease index (OSDI), tear breakup time (TBUT), corneal fluorescein staining, and lissamine staining, have great deal of variability. We investigated whether fluorophotometry correlated with previously established DED diagnostic tests and whether it could serve as a novel objective metric to evaluate DED. Dry eye patients who have had established signs or symptoms for at least 6 months were included in this observational study. Normal subjects with no symptoms of dry eyes served as controls. Each eye had a baseline fluorescein scan prior to any fluorescein dye. Fluorescein dye was then placed into both eyes, rinsed with saline solution, and scanned at 5, 10, 15, and 30 min. Patients were administered the following diagnostic tests to correlate with fluorophotometry: OSDI, TBUT, fluorescein, and lissamine. Standard protocols were used. P < 0.05 was considered significant. Fifty eyes from 25 patients (DED = 22 eyes, 11 patients; Normal = 28 eyes, 14 patients) were included. Baseline scans of the dry eye and control groups did not show any statistical difference (p = 0.84). Fluorescein concentration of DED and normal patients showed statistical significance at all time intervals (p < 10(-5), 0.001, 0.002, 0.049 for 5, 10, 15, & 30 min respectively). Fluorophotometry values converged towards baseline as time elapsed, but both groups were still statistically different at 30 min (p < 0.01). We used four fluorophotometry scoring methods and correlated them with OSDI, TBUT, fluorescein, and lissamine along with adjusted and aggregate scores. The four scoring schemes did not show any significant correlations with the other tests, except for correlations seen with lissamine and 10 (p = 0.045, 0.034) and 15 min (p = 0.013, 0.012), and with aggregate scores and 15 min (p = 0.042, 0.017). Fluorophotometry generally did not correlate with any other DED tests, even though it showed capability of differentiating between DED and normal eyes up to 30 min after fluorescein dye instillation. There may be an aspect of DED that is missed in the current regimen of DED tests and only captured with fluorophotometry. Adding fluorophotometry may be useful in screening, diagnosing, and monitoring patients with DED.

  2. Noninvasive monitoring of intraocular pharmacokinetics of daunorubicin using fluorophotometry.

    PubMed

    Kizhakkethara, I; Li, X; el-Sayed, S; Khoobehi, B; Moshfeghi, D M; Rahimy, M; Peyman, G A

    Daunorubicin is a cytotoxic drug, which, in nontoxic doses, is effective in preventing cellular proliferation in experimental vitreoretinopathy. We studied dose and clearance of daunorubicin in various ocular tissues using fluorophotometry techniques. In vitro tests: The emission of fluorescence from the daunorubicin solution having a concentration range of 0.1 to 10 micrograms/mL in phosphate buffer was measured using an excitation wavelength range of 489 +/- 10 nm. The emission of fluorescence was measured at 514 nm; the linearity of the response was determined using linear regression analysis. There is a fluorescence peak of daunorubicin at 485 nm. The validity and reproducibility of the method were examined. In vivo tests: The rabbits were randomized into three groups and daunorubicin concentrations of 4, 6, or 8 micrograms/mL were injected into the vitreous. Fluorophotometry scanning from the retina to the anterior chamber was performed with a commercially available fluorophotometer at various times up to 48 hours after injection to quantify fluorescence emission of daunorubicin. The standard curve of fluorescence versus concentration of daunorubicin was linear in the range of 0.1 to 8 micrograms/mL. It was sensitive up to 0.1 microgram. The daunorubicin time concentration profile showed a dose response relationship over the 48-hour period studied. The half-life of daunorubicin in the vitreous was about 5 hours. We performed fluorophotometry using a fluorophotometer whose exciter emits light at 489 nm, which is very close to an absorption peak of daunorubicin. These two values are close enough to obviate the need for modifying the commercial fluorophotometer. Therefore the concentration of daunorubicin in the vitreous cavity can be measured noninvasively.

  3. Study of lens autofluorescence by fluorophotometry in pregnant patients with diabetes.

    PubMed

    Beneyto, P; Alonso, I; Pérez, T M; López, L; Fonseca, A

    1996-05-01

    Lens autofluorescence originates from an accumulation of fluorescent substances such as the tryptophan-derived residues and glycosylated protein aggregations, which are associated with the process of cataractogenesis and lens aging. The purpose of this investigation is to determine whether pregnancy alters the typical constituents of the lens autofluorescence in patients with diabetes and, if so, to what degree this may occur. Lens autofluorescence was studied with fluorophotometry in 127 eyes of 72 individuals: 23 control subjects, 6 healthy pregnant women, 21 patients with diabetes, and 44 pregnant patients with diabetes. The autofluorescence values were 311 +/- 130 ng/ml, 253 +/- 40 ng/ml, 378 +/- 110 ng/ml, and 562 +/- 164 Eq ng/ml (Eq ng/ml = Ng/ml equivalent fluorescein) in the four groups, respectively. The difference between the nonpregnant and pregnant patients with diabetes was significant (P < 0.001). These results suggest that there is an important deterioration in the metabolic state of the lens during gestation in patients with diabetes, as is the case for diabetic retinopathy.

  4. Functionalized Ni@SiO2 core/shell magnetic nanoparticles as a chemosensor and adsorbent for Cu2+ ion in drinking water and human blood.

    PubMed

    Park, Minsung; Seo, Sungmin; Lee, Soo Jin; Jung, Jong Hwa

    2010-11-01

    Fluorogenic based nitrobenzofuran-functionalized Ni@SiO(2) core/shell magnetic nanoparticles have been prepared by sol-gel grafting reaction. Their ability to detect and remove metal ions was evaluated by fluorophotometry. The nanoparticles exhibited a high affinity and selectivity for Cu(2+) over competing metal ions. Furthermore, the nanoparticles efficiently removed Cu(2+) in drinking water and human blood.

  5. Specialized Diagnostic Investigations to Assess Ocular Status in Hypertensive Diseases of Pregnancy.

    PubMed

    Bakhda, Rahul Navinchandra

    2016-04-22

    This review describes specialized diagnostic investigations to assess ocular status in hypertensive diseases of pregnancy. Ocular assessment can aid in early detection for prompt multidisciplinary treatment, obstetric intervention and follow-up. The investigations accurately predict the possible causes of blindness in hypertensive diseases of pregnancy. The investigations include fluorescein angiography, ophthalmodynamometry, fluorophotometry, imaging modalities, OCT, ultrasonography, doppler velocimetry and blood chemistry analysis. The review includes a summary of imaging techniques and related recent developments to assess the neuro-ophthalmic aspects of the disease. The imaging modalities have been instrumental in understanding the complex neuropathophysiological mechanisms of eclamptic seizures. The importance of blood chemistry analysis in hypertensive diseases of pregnancy has been emphasized. The investigations have made a significant contribution in improving the standards of antenatal care and reducing maternal and fetal morbidity and mortality.

  6. Specialized Diagnostic Investigations to Assess Ocular Status in Hypertensive Diseases of Pregnancy

    PubMed Central

    Bakhda, Rahul Navinchandra

    2016-01-01

    This review describes specialized diagnostic investigations to assess ocular status in hypertensive diseases of pregnancy. Ocular assessment can aid in early detection for prompt multidisciplinary treatment, obstetric intervention and follow-up. The investigations accurately predict the possible causes of blindness in hypertensive diseases of pregnancy. The investigations include fluorescein angiography, ophthalmodynamometry, fluorophotometry, imaging modalities, OCT, ultrasonography, doppler velocimetry and blood chemistry analysis. The review includes a summary of imaging techniques and related recent developments to assess the neuro-ophthalmic aspects of the disease. The imaging modalities have been instrumental in understanding the complex neuropathophysiological mechanisms of eclamptic seizures. The importance of blood chemistry analysis in hypertensive diseases of pregnancy has been emphasized. The investigations have made a significant contribution in improving the standards of antenatal care and reducing maternal and fetal morbidity and mortality. PMID:28933399

  7. [Clinical study of the effectiveness of a dexpanthenol containing artificial tears solution (Siccaprotect) in treatment of dry eyes].

    PubMed

    Göbbels, M; Gross, D

    1996-01-01

    In this controlled, randomized, double-masked study the effect of dexpanthenol-containing artificial tears (Siccaprotect) on patients with dry eyes was examined. 50 patients applied either dexpanthenol-containing artificial tears (Siccaprotect) or the identical, but free of dexpanthenol, eye drops five times daily into the conjunctival sac. No other ophthalmics were administered. The corneal epithelial permeability was measured by fluorophotometry and Schirmer-Test, Rose Bengal staining, tear film break-up time and the patients' subjective complaints were determined before and after 6 weeks of treatment. The dexpanthenol-containing artificial tears (Siccaprotect) improved disturbances of the corneal epithelial permeability significantly in comparison to the dexpanthenol-free eyes drops. The other parameters didn't show relevant differences. These data suggest that, in dry eyes, treatment with dexpanthenol-containing eye drops leads to a favorable and comparing with dexpanthenol-free eye drops superior improvement in disturbances of corneal epithelium permeability.

  8. Tear exchange and contact lenses: A review

    PubMed Central

    Muntz, Alex; Subbaraman, Lakshman N.; Sorbara, Luigina; Jones, Lyndon

    2015-01-01

    Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses. PMID:25575892

  9. [Effect of protopine on rabbit platelet function].

    PubMed

    Ma, G Y; Zhang, Z Z; Chen, Z H

    1994-07-01

    Protopine (Pro) inhibited dose-dependently rabbit platelet aggregation induced by ADP, arachidonic acid (AA), collagen, or aggregoserpentin of Trimeresurus mucrosquamatus venom (TMVA) in vitro. Their IC50 were 25.3, 30.5, 46.9, 33.4 mumol.L-1, respectively. Pro 10, 20 mg.kg-1 iv also inhibited the platelet aggregation induced by these inducers. The effects (maximal at 5 min) lasted 1 h. By using fluorophotometry and RIA, it was seen that Pro suppressed the release of 5-HT from platelets during aggregation induced by collagen, AA, or TMVM in vitro. Pro did not block the formation of thromboxane A2 during aggregation induced by AA and did not increase the content of cAMP in rabbit platelet, but increased the content of cGMP in rabbit platelets. The antiplatelet effect of Pro may be related to an increase cGMP in rabbit platelets and the suppression of the release of the active substances from platelets.

  10. Summary of studies on the blue-green autofluorescence and light transmission of the ocular lens

    NASA Astrophysics Data System (ADS)

    Van Best, Jaap A.; Kuppens, Esmeralda V.

    1996-07-01

    This paper reviews previous work done to demonstrate the clinical relevance of the measurement of blue-green autofluorescence and light transmission of the ocular lens. These can be determined quantitatively with fluorophotometry in a few seconds. Autofluorescence and transmission values are determined in healthy volunteers, in patients with insulin-dependent diabetes mellitus, and in patients with untreated glaucoma or untreated ocular hypertension. The lens autofluorescence of healthy volunteers increased linearly and transmission decreased exponentially with age. Each year of diabetes induced an increase of autofluorescence equal to one extra year of age. Untreated glaucoma or ocular hypertension had no significant effect on lens autofluorescence and transmission. Increased autofluorescence and decreased transmission values in comparison with values of a healthy population are proved to be indicative for an increased risk of developing cataract and the clinical usefulness of these measures is demonstrated. Diabetes is a risk factor for developing cataracts while untreated glaucoma or ocular hypertension is not.

  11. Tear exchange and contact lenses: a review.

    PubMed

    Muntz, Alex; Subbaraman, Lakshman N; Sorbara, Luigina; Jones, Lyndon

    2015-01-01

    Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  12. Topical timolol with and without benzalkonium chloride: epithelial permeability and autofluorescence of the cornea in glaucoma.

    PubMed

    de Jong, C; Stolwijk, T; Kuppens, E; de Keizer, R; van Best, J

    1994-04-01

    Epithelial permeability and autofluorescence of the cornea were determined by fluorophotometry in 21 patients with open-angle glaucoma or ocular hypertension using timolol medication with the preservative benzalkonium chloride (BAC) and 2 weeks after changing to timolol medication without BAC. The investigation was performed to determine whether removal of BAC would reduce toxic effects on the cornea and complaints of sensations of burning or dry eye. Corneal epithelial permeability decreased significantly after changing medication (mean decrease per patient 27%, P = 0.025). Corneal autofluorescence increased significantly after changing medication suggesting an alteration in corneal metabolism (mean increase per patient 6%, P = 0.003). Timolol without BAC was found to be as effective as timolol with BAC in reducing intraocular pressure (P = 0.4). Removal of BAC from timolol resulted in an improvement of corneal epithelial barrier function and in a reduction of complaints. The improvement was found to be proportional to the duration of the preceding BAC-containing therapy.

  13. Study on the interaction between albendazole and eosin Y by fluorescence, resonance Rayleigh scattering and frequency doubling scattering spectra and their analytical applications

    NASA Astrophysics Data System (ADS)

    Tian, Fengling; Huang, Wei; Yang, Jidong; Li, Qin

    In pH 3.25-3.35 Britton-Robinson (BR) buffer solution, albendazole (ABZ) could react with eosin Y (EY) to form a 1:1 ion-association complex, which not only results in the quenching of fluorescence, but also resulted in the great enhancement of resonance Rayleigh scattering (RRS) and frequency doubling scattering (FDS). Furthermore, a new RRS spectrum will appear, and the maximum RRS wavelength was located at about 356 nm. The detection limit for ABZ were 21.51 ng mL-1 for the fluorophotometry, 6.93 ng mL-1 for the RRS method and 12.89 ng mL-1 for the FDS method. Among them, the RRS method had the highest sensitivity. The experimental conditions were optimized and effects of coexisting substances were evaluated. Meanwhile, the influences of coexisting substances were tested. The methods have been successfully applied to the determination of ABZ in capsules and human urine samples. The composition and structure of the ion-association complex and the reaction mechanism were discussed.

  14. The tear turnover and tear clearance tests - a review.

    PubMed

    Garaszczuk, Izabela K; Montes Mico, Robert; Iskander, D Robert; Expósito, Alejandro Cerviño

    2018-03-01

    The aim is to provide a summary of methods available for the assessment of tear turnover and tear clearance rates. The review defines tear clearance and tear turnover and describes their implication for ocular surface health. Additionally, it describes main types of techniques for measuring tear turnover, including fluorescein tear clearance tests, techniques utilizing electromagnetic spectrum and tracer molecule and novel experimental techniques utilizing optical coherence tomography and fluorescein profilometry. Areas covered: Internet databases (PubMed, Science Direct, Google Scholar) and most frequently cited references were used as a principal resource of information on tear turnover rate and tear clearance rate, presenting methodologies and equipment, as well as their definition and implications for the anterior eye surface health and function. Keywords used for data-search were as follows: tear turnover, tear clearance, fluorescein clearance, scintigraphy, fluorophotometry, tear flow, drainage, tear meniscus dynamics, Krehbiel flow and lacrimal functional unit. Expert commentary: After decades, the topic of tear turnover assessment has been reintroduced. Recently, new techniques have been developed to propose less invasive, less time consuming and simpler methodologies for the assessment of tear dynamics that have the potential to be utilized in clinical practice.

  15. Corneal epithelial barrier function after oxybuprocaine provocation in diabetics.

    PubMed

    Stolwijk, T R; van Best, J A; Boor, J P; Lemkes, H H; Oosterhuis, J A

    1990-03-01

    Corneal epithelial permeability for fluorescein was determined after provocation by a local anesthetic in 18 non-insulin-dependent diabetes mellitus (NIDDM) patients, 23 insulin-dependent diabetes mellitus (IDDM) patients, and 22 healthy controls to evaluate the corneal epithelial barrier function in diabetes. All volunteers had Oxybuprocaine instilled into one eye and saline into the other eye. The epithelial permeability values were determined by fluorophotometry, and the ratio between both eyes was calculated for each individual. The mean permeability values of the saline-instilled eyes in the diabetic patients did not differ significantly from those in the healthy controls (P greater than 0.2). The individual ratios between Oxybuprocaine- and saline-instilled eyes in the NIDDM and IDDM patients differed significantly from those in the healthy controls (mean ratios: 2.6, 1.9, and 1.0, respectively; P less than 0.002). The permeability ratios and the percentage glycosylated hemoglobin (HbAlc) were linearly correlated in the NIDDM patients but not in the IDDM patients (r = 0.73, P less than 0.001, and r = 0.09, P greater than 0.68, respectively). The results showed that the corneal epithelial barrier function in the diabetic patients was not impaired compared with that in the healthy controls. After provocation by a local anesthetic, the barrier function was impaired in the diabetic patients only.

  16. Synthesis of superparamagnetic iron oxide nanoparticles coated with a DDNP-carboxyl derivative for in vitro magnetic resonance imaging of Alzheimer's disease.

    PubMed

    Zhou, Jingting; Fa, Huanbao; Yin, Wei; Zhang, Jin; Hou, Changjun; Huo, Danqun; Zhang, Dong; Zhang, Haifeng

    2014-04-01

    Superparamagnetic iron oxide nanoparticles (SPIONs) have been proposed for use in magnetic resonance imaging as versatile ultra-sensitive nanoprobes for Alzheimer's disease imaging. In this work, we synthetized an efficient contrast agent of Alzheimer's disease using 1,1-dicyano-2-[6-(dimethylamino)naphthalene-2-yl]propene (DDNP) carboxyl derivative to functionalize the surface of SPIONs. The DDNP-SPIONs are prepared by conjugating DDNP carboxyl derivative to oleic acid-treated SPIONs through ligand exchange. The structure, size distribution and magnetic property were identified by IR, TGA-DTA, XRD, TEM, Zetasizer Nano and VSM. TEM and Zetasizer Nano observations indicated that the DDNP-SPIONs are relatively mono-dispersed spherical distribution with an average size of 11.7nm. The DDNP-SPIONs were then further analyzed for their MRI relaxation properties using MR imaging and demonstrated high T2 relaxivity of 140.57s(-1)FemM(-1), and the vitro experiment that DDNP-SPIONs binding to β-Amyloid aggregates were then investigated by fluorophotometry, the results showed that the combination had induced the fluorescence enhancement of the DDNP-SPIONs and displayed tremendous promise for use as a contrast agent of Alzheimer's disease in MRI. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Photocoagulation as treatment of diabetic retinopathy

    NASA Astrophysics Data System (ADS)

    Sanchez, J.; Fernandez, L.; de Pedraza, Maria L.; Gamella, C.; Santervas, R.

    1992-03-01

    Diabetes Mellitus is a chronic disease that is revealed with a lot of alterations due to factors such as an absolute or relative reduction of the insulin. It is usually accompanied by generalized arteriosclerosis and prepares for certain microvasculares pathologies such as retinopathy, nefropathy, and neuropathy. The first effects of diabetes in the retina seem to act on the capillaries. The functional modifications of the retinal circulation appear before the structural ones. These consist of the blood flux damage and the obligation of the hematorretinal barrier with extravasacy as can be proved in the fluorophotometry of the vitreous humor. Nowadays, medical treatments are more effective and only vitrectomy and photocoagulation are used in diabetic retinopathy. For that, the argon laser and the xenon arch are used. The treatment is usually spread panretine, with coagulation in a grid pattern around the eye, avoiding the macula and other vital structures, and treating the neoformed blood vessels. The rate of grave visual loss in the studies carried out with there techniques was 12 in relation to 28 in the non-treated cases. The most important factors of risk found, were the discal neoformed blood vessels and the hemorrhage of the vitreous humor. Adverse effects were found such as the reduction of visual sharpness and the contrition of the visual field, these are greater in patients treated with the xenon arch than in those treated with the argon laser.

  18. [Effect of Coriolus versicolor polysaccharide B on membrane glycosaminoglycans and cellular glutathione changes in RAW264.7 macrophages exposed to angiotensin II].

    PubMed

    Lou, Ning; Ma, Gang; Wang, Dao-feng; Zhu, Zhi-wei; Su, Quan-guan; Fang, Yi

    2007-12-01

    To investigate the effect of Coriolus versicolor polysaccharide B (CVP-B) on increased membrane glycosaminoglycans (GAG) expression and intracellular glutathione (GSH) of RAW264.7 macrophages exposed to angiotensin II (Ang II). The plasma membrane of RAW264.7 macrophages exposed to Ang II treatment was isolated by ultracentrifugation, and the membrane GAG expression was analyzed using 1, 9-dimethylmethylene blue (DMMB) spectrophotometric assay for sulfated GAG. The intracellular reduced GSH was determined using fluorophotometry. The GAG content in the macrophage membranes increased by up to 54% following cell exposure to 1.0 micromol/L Ang II, whereas in presence of 1.0 micromol;/L Ang II, CVP-B at 1, 10, and 50 microg/ml decreased the GAG content by 13%, 43% (P<0.01), and 52% (P<0.01), respectively. The macrophage GSH activity decreased by 69% following incubation with 1.0 micromol;/L Ang II for 24 h, and CVP-B treatment at 1, 10, and 50 microg/ml in presence of 1.0 micromol;/L Ang II resulted in significant increment of GSH activity by 31%(P<0.05), 104% (P<0.01), and 168% (P<0.01), respectively. These data provide the first evidence that CVP-B inhibits elevated GAG expression in RAW264.7 macrophage membrane induced by Ang II.

  19. Sildenafil Stimulates Aqueous Humor Turnover in Rabbits

    PubMed Central

    Alvarez, Lawrence J.; Zamudio, Aldo C.; Candia, Oscar A.

    2013-01-01

    Sildenafil citrate increases ocular blood flow and accelerates the rate of anterior chamber refilling after paracentesis. The latter effect could have resulted from a reduction in outflow facility or from an increase in aqueous humor (AH) production. In this study, we used scanning ocular fluorophotometry to examine the effects of sildenafil on AH turnover, and thus, AH production in eyes of live normal rabbits. For this, the rate of aqueous humor flow (AHF) was quantified with a commercially available fluorophotometer that measured the rate of fluorescein clearance from the anterior segment, which predominantly occurs via the trabecular meshwork. After ≈ 2 hrs of control scans to determine the baseline rate of AHF, the rabbits were fed 33 mg of sildenafil and allowed ≈ 45 min for the drug to enter the systemic circulation. Thereafter, fluorescence scans were retaken for an additional 90–120 min. Sildenafil ingestion increased AHF by about 36%, from 2.31 μL/min to 3.14 μL/min (P< 0.001, as two-tailed paired data, n= 20 eyes). This observation indicates that sildenafil citrate, which is a phosphodiesterase type-5 inhibitor currently marketed as a vasodilator (e.g., Viagra, Revatio), stimulates AHF in rabbits. Our results seem consistent with reports indicating that the drug dilates intraocular arteries and augments intraocular vascular flow. These physiological responses to the agent apparently led to increased fluid entry into the anterior chamber. As such, the drug might have utility in patients with ocular hypotony resulting from insufficient AH formation. PMID:23562660

  20. Fluorophotometric determination of aqueous humor flow rates in red-tailed hawks (Buteo jamaicensis).

    PubMed

    Jones, Michael P; Ward, Daniel A

    2012-04-01

    To determine aqueous humor flow rate (AHFR) in an avian species by use of anterior segment fluorophotometry. 9 healthy red-tailed hawks (Buteo jamaicensis; 4 males and 5 females) that ranged from 8 months to 8 years of age. A protocol was developed for fluorophotometric determination of AHFR. Topical administration of 10% fluorescein was used to load the corneas, and corneal and aqueous humor fluorescein concentrations were measured approximately 5, 6.5, and 8 hours later. Concentration-versus-time plots were generated, and slopes and cornea-to-aqueous humor concentration ratios from these plots were used to manually calculate flow rates. Mean ± SD AHFRs for the right eye, left eye, and both eyes were 3.17 ± 1.36 μL/min (range, 1.67 to 6.21 μL/min), 2.86 ± 0.88 μL/min (range, 2.04 to 4.30 μL/min), and 2.90 ± 0.90 μL/min (range, 1.67 to 4.42 μL/min), respectively. The AHFRs were similar for right and left eyes. These flow rates represented a mean aqueous humor transfer coefficient of 0.0082/min, which is similar to that of mammalian species. The AHFR in red-tailed hawks was similar to that of most mammalian species, and the fractional egress was almost identical to that of other species. This information will allow a greater understanding of aqueous humor flow in avian eyes, which is crucial when evaluating diseases that affect avian eyes as well as medications that alter aqueous humor flow.

  1. Sepsis-induced alteration in T-cell Ca(2+) signaling in neonatal rats.

    PubMed

    Alattar, M H; Ravindranath, T M; Choudhry, M A; Muraskas, J K; Namak, S Y; Dallal, O; Sayeed, M M

    2001-01-01

    Sepsis-induced suppression in T-cell proliferation follows deranged Ca(2+) signaling in adult rats. In preliminary studies, we observed suppression in T-cell proliferation in septic neonatal rats as well. In this study, we assessed splenic T-cell cytosolic Ca(2+) concentration, [Ca(2+)](i), as its elevation plays an important role in T-cell proliferation. Also, we investigated the role of PGE(2) in sepsis-related changes in T-cell [Ca(2+)](i) in animals pretreated with cyclooxygenase-1 (COX-1) inhibitor (resveratrol) and cyclooxygenase-2 (COX-2) inhibitor (NS-398). Sepsis was induced in 15-day-old rat pups by intraperitoneal implantation of fecal pellets containing Escherichia coli and Bacteroides fragilis. The sham group consisted of pups implanted with sterile fecal pellets. Septic and sham pups were sacrificed 24 h after implantation and their spleens were removed. The spleens from sham and septic pups, along with spleens from unoperated control pups, were processed for single cell suspensions, and T cells were isolated using nylon wool columns. Fura-2 fluorophotometry was employed for the measurement of [Ca(2+)](i) (in nM units) in T cells stimulated with concanavalin A (ConA). Our results show that ConA-mediated T-cell [Ca(2+)](i) response is significantly suppressed in septic neonatal rats. Pretreatment of pups with COX-2, but not COX-1 inhibitor, prevented the decrease in the [Ca(2+)](i) response. These findings suggest that PGE(2) might induce the attenuation in T-cell Ca(2+) signaling during sepsis in neonatal rats. Copyright 2001 S. Karger AG, Basel

  2. The effect of rebamipide ophthalmic suspension on ocular surface mucins in soft contact lens wearers.

    PubMed

    Shigeyasu, Chika; Yamada, Masakazu; Akune, Yoko; Fukui, Masaki

    2017-12-13

    To evaluate the changes in ocular surface mucins with 2%rebamipide ophthalmic suspension treatment in soft contact lens (SCL) wearers. Rebamipide suspension is a mucin secretagogue approved for the treatment of dry eye syndrome in Japan. In this study, the fluorescence intensity of wheat germ agglutinin conjugate of fluorescein (F-WGA) was used as a marker of membrane-associated mucins, and sialic acid concentration in tear fluids as a marker of secreted mucins. Thirty-two eyes of 16 SCL wearers with discomfort were treated with rebamipide suspension at a dose of one drop in each eye four times daily for two weeks. The parameters of clinical efficacy were tear break-up time, fluorescein staining scores for the cornea and conjunctiva, and Schirmer test values. Fluorescence intensities in the central cornea were measured by fluorophotometry after the application of 5% F-WGA solution. Tears collected by Schirmer test strips were analyzed by high-performance liquid chromatography, and the concentrations of sialic acid, total protein, and the four major tear proteins, namely secretory IgA, lactoferrin, lipocalin-1, and lysozyme were measured. Significant increases in F-WGA fluorescence intensities (p < 0.005) were seen in the corneal surfaces. Sialic acid concentrations increased over time; however, the differences were not statistically significant. Except for a slight increase in kerato-conjunctival staining scores (p < 0.05) and secretory IgA (p < 0.05), no other significant differences were seen among clinical parameters or tear proteins. Topical application of rebamipide suspension significantly increased F-WGA intensity, a marker of membrane-associated mucins in SCL wearers. Copyright © 2017 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  3. Nanoparticles in Porous Microparticles Prepared by Supercritical Infusion and Pressure Quench Technology for Sustained Delivery of Bevacizumab

    PubMed Central

    K.Yandrapu, Sarath; Upadhyay, Arun K.; Petrash, J. Mark; Kompella, Uday B.

    2014-01-01

    Nanoparticles in porous microparticles (NPinPMP), a novel delivery system for sustained delivery of protein drugs, was developed using supercritical infusion and pressure quench technology, which does not expose proteins to organic solvents or sonication. The delivery system design is based on the ability of supercritical carbon dioxide (SC CO2) to expand poly(lactic-co-glycolic) acid (PLGA) matrix but not polylactic acid (PLA) matrix. The technology was applied to bevacizumab, a protein drug administered once a month intravitreally to treat wet age related macular degeneration. Bevacizumab coated PLA nanoparticles were encapsulated into porosifying PLGA microparticles by exposing the mixture to SC CO2. After SC CO2 exposure, the size of PLGA microparticles increased by 6.9 fold. Confocal and scanning electron microscopy studies demonstrated the expansion and porosification of PLGA microparticles and infusion of PLA nanoparticles inside PLGA microparticles. In vitro release of bevacizumab from NPinPMP was sustained for 4 months. Size exclusion chromatography, fluorescence spectroscopy, circular dichroism spectroscopy, SDS-PAGE, and ELISA studies indicated that the released bevacizumab maintained its monomeric form, conformation, and activity. Further, in vivo delivery of bevacizumab from NPinPMP was evaluated using noninvasive fluorophotometry after intravitreal administration of Alexa Flour 488 conjugated bevacizumab in either solution or NPinPMP in a rat model. Unlike the vitreal signal from Alexa-bevacizumab solution, which reached baseline at 2 weeks, release of Alexa-bevacizumab from NPinPMP could be detected for 2 months. Thus, NPinPMP is a novel sustained release system for protein drugs to reduce frequency of protein injections in the therapy of back of the eye diseases. PMID:24131101

  4. Nanoparticles in porous microparticles prepared by supercritical infusion and pressure quench technology for sustained delivery of bevacizumab.

    PubMed

    Yandrapu, Sarath K; Upadhyay, Arun K; Petrash, J Mark; Kompella, Uday B

    2013-12-02

    Nanoparticles in porous microparticles (NPinPMP), a novel delivery system for sustained delivery of protein drugs, was developed using supercritical infusion and pressure quench technology, which does not expose proteins to organic solvents or sonication. The delivery system design is based on the ability of supercritical carbon dioxide (SC CO2) to expand poly(lactic-co-glycolic) acid (PLGA) matrix but not polylactic acid (PLA) matrix. The technology was applied to bevacizumab, a protein drug administered once a month intravitreally to treat wet age related macular degeneration. Bevacizumab coated PLA nanoparticles were encapsulated into porosifying PLGA microparticles by exposing the mixture to SC CO2. After SC CO2 exposure, the size of PLGA microparticles increased by 6.9-fold. Confocal and scanning electron microscopy studies demonstrated the expansion and porosification of PLGA microparticles and infusion of PLA nanoparticles inside PLGA microparticles. In vitro release of bevacizumab from NPinPMP was sustained for 4 months. Size exclusion chromatography, fluorescence spectroscopy, circular dichroism spectroscopy, SDS-PAGE, and ELISA studies indicated that the released bevacizumab maintained its monomeric form, conformation, and activity. Further, in vivo delivery of bevacizumab from NPinPMP was evaluated using noninvasive fluorophotometry after intravitreal administration of Alexa Fluor 488 conjugated bevacizumab in either solution or NPinPMP in a rat model. Unlike the vitreal signal from Alexa-bevacizumab solution, which reached baseline at 2 weeks, release of Alexa-bevacizumab from NPinPMP could be detected for 2 months. Thus, NPinPMP is a novel sustained release system for protein drugs to reduce frequency of protein injections in the therapy of back of the eye diseases.

  5. Effects of dorzolamide on choroidal blood flow, ciliary blood flow, and aqueous production in rabbits.

    PubMed

    Reitsamer, Herbert A; Bogner, Barbara; Tockner, Birgit; Kiel, Jeffrey W

    2009-05-01

    To determine the effects of topical dorzolamide (a carbonic anhydrase inhibitor) on choroidal and ciliary blood flow and the relationship between ciliary blood flow and aqueous flow. The experiments were performed in four groups of pentobarbital-anesthetized rabbits treated with topical dorzolamide (2%, 50 microL). In all groups, intraocular pressure (IOP) and mean arterial pressure (MAP) at the eye level were measured continuously by direct cannulation. In group 1, aqueous flow was measured by fluorophotometry before and after dorzolamide treatment. In group 2, aqueous flow was measured after dorzolamide at normal MAP and while MAP was held constant at 80, 55, or 40 mm Hg with occluders on the aorta and vena cava. In group 3, the same MAP levels were used, and ciliary blood flow was measured transsclerally by laser Doppler flowmetry (LDF). In group 4, choroidal blood flow was measured by LDF with the probe tip positioned in the vitreous over the posterior pole during ramp increases and decreases in MAP before and after dorzolamide. Dorzolamide lowered IOP by 19% (P < 0.01) and aqueous flow by 17% (P < 0.01), and increased ciliary blood flow by 18% (P < 0.01), which was associated with a significant reduction in ciliary vasculature resistance (-7%, P < 0.01). Dorzolamide shifted the relationship between ciliary blood flow and aqueous flow downward relative to the previously determined control relationship in the rabbit. Dorzolamide did not alter choroidal blood flow, choroidal vascular resistance, or the choroidal pressure flow relationship. Acute topical dorzolamide is a ciliary vasodilator and has a direct inhibitory effect on aqueous production, but it does not have a detectable effect on choroidal hemodynamics at the posterior pole in the rabbit.

  6. A sensitive and selective chemosensor for GSSG detection based on the recovered fluorescence of NDPA-Fe₃O₄@SiO₂-Cu(II) nanomaterial.

    PubMed

    Ma, Ya; Zheng, Baozhan; Zhao, Yan; Yuan, Hongyan; Cai, Yuqing; Du, Juan; Xiao, Dan

    2013-10-15

    A sensitive and selective sensor for oxidized glutathione (GSSG) detection based on the recovered fluorescence of naphthalimide-DPA (NDPA)-Fe₃O₄@SiO₂-Cu(II) system is reported. NDPA-Fe3Fe₃O₄@SiO₂ was characterized by X-ray power diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectra (FT-IR) and fluorophotometry. The fluorescence of NDPA-Fe₃O₄@SiO₂ could be quenched by Cu²⁺ due to the coordination of Cu²⁺ with the tridentate receptor DPA. This coordination process reduced the electron-donating ability of the nitrogen atom in the DPA moiety, thus suppressing the internal charge transfer (ICT) process in NDPA-Fe₃O₄@SiO₂. In the presence of GSSG, the fluorescence of NDPA-Fe₃O₄@SiO₂-Cu(II) was recovered because of strong coordination of Cu²⁺ with GSSG, which promoted the decomplexation between NDPA-Fe₃O₄@SiO₂ and Cu²⁺, and enhanced the ICT process. The NDPA-Fe₃O₄@SiO₂-Cu(II) nanomaterial exhibited high sensitivity towards GSSG, and a good linear relationship was obtained from 5 nM to 60 μM. The limit of detection, based on a signal-to-noise ratio of 3, was 50 pM. In addition, the presence of magnetic Fe₃O₄ nanoparticles (NPs) in NDPA-Fe₃O₄@SiO₂ NPs would also facilitate the magnetic separation of NDPA-Fe₃O₄@SiO₂ from the solution. Through the use of added internal standards, we successfully determined the concentration of GSSG in HEK 293 cell lysate to be 1.15 μM by the prepared chemsensor NDPA-Fe₃O₄@SiO₂-Cu(II). The proposed method is anticipated to fabricate other sensitive fluorescence sensors based on organic-inorganic hybrid magnetic nanoparticles. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Effects of head down tilt on episcleral venous pressure in a rabbit model.

    PubMed

    Lavery, W J; Kiel, J W

    2013-06-01

    In humans, changing from upright to supine elicits an approximately 10 mmHg increase in cephalic venous pressure caused by the hydrostatic column effect, but episcleral venous pressure (EVP) and intraocular pressure (IOP) rise by only a few mmHg. The dissociation of the small increases in IOP and EVP compared to the larger increase in cephalic venous pressure suggests a regulatory mechanism controlling EVP. The aim of the present study was to determine if the rabbit model is suitable to study the effects of postural changes on EVP despite its short hydrostatic column. In anesthetized rabbits (n = 43), we measured arterial pressure (AP), IOP, and orbital venous pressure (OVP) by direct cannulation; carotid blood flow (BFcar) by transit time ultrasound, heart rate (HR) by digital cardiotachometer, and EVP with a servonull micropressure system. The goal of the protocol was to obtain measurement of supine EVP for ≈10 min, followed by ≈10 min of EVP measurement with the rabbit in a head down tilt. The data were analyzed by paired t-tests and the results reported as the mean ± standard error of the mean. In a separate group of animals (n = 35), aqueous flow was measured by fluorophotometry. This protocol entailed measurement of aqueous flow in the supine position for ≈60 min, followed by ≈60 min of aqueous flow measurement with the rabbit in a head down tilt. From supine to head down tilt, AP and BFcar were unchanged, IOP increased by 2.3 ± 0.4 mmHg (p < 0.001), EVP increased by 2.4 ± 0.4 mmHg (p < 0.001), OVP increased by 2.5 ± 0.2 mmHg (p < 0.001) and HR decreased by 9 ± 3 bpm (p = 0.002). Head down tilt caused no significant change in aqueous flow. Although the hydrostatic column in the rabbit is shorter than humans, the rabbit model permits sufficiently sensitive measurements of the pressures and systemic parameters likely involved in the EVP responses to posture change. The present results indicate directionally similar EVP and IOP responses to tilt as occur in humans and, as in humans, the responses are smaller than would be expected from the change in the hydrostatic column height. Also, as in humans, the model reveals no change in aqueous flow during head down tilt. We conclude the rabbit model is appropriate for studying the mechanisms responsible for the relative immunity of EVP and IOP to posture change. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Suprachoroidal delivery in a rabbit ex vivo eye model: influence of drug properties, regional differences in delivery, and comparison with intravitreal and intracameral routes

    PubMed Central

    Kadam, Rajendra S.; Williams, Jason; Tyagi, Puneet; Edelhauser, Henry F.

    2013-01-01

    Purpose First, to determine the influence of drug lipophilicity (using eight beta-blockers) and molecular weight (using 4 kDa and 40 kDa fluoroscein isothiocyanate [FITC]-dextrans) on suprachoroidal delivery to the posterior segment of the eye by using a rabbit ex vivo eye model. Second, to determine whether drug distribution differs between the dosed and undosed side of the eye following suprachoroidal delivery. Third, to compare the suprachoroidal delivery of sodium fluorescein (NaF) with the intracameral and intravitreal routes by using noninvasive fluorophotometry. Methods Using a small hypodermic 26G needle (3/8”) with a short bevel (250 µm), location of the suprachoroidal injection in an ex vivo New Zealand white rabbit eye model was confirmed with India ink. Ocular tissue distribution of NaF (25 µl of 1.5 µg/ml) at 37 °C was monitored noninvasively using the Fluorotron MasterTM at 0, 1, and 3 h following suprachoroidal, intravitreal, or intracameral injections in ex vivo rabbit eyes. For assessing the influence of lipophilicity and molecular size, 25 µl of a mixture of eight beta-blockers (250 µg/ml each) or FITC-dextran (4 kDa and 40 kDa, 30 mg/ml) was injected into the suprachoroidal space of excised rabbit eyes and incubated at 37 °C. Eyes were incubated for 1 and 3 h, and frozen at the end of incubation. Ocular tissues were isolated in frozen condition. Beta-blocker and FITC-dextran levels in excised ocular tissue were measured by liquid chromatography–tandem mass spectrometry and spectrofluorometry, respectively. Results Histological sections of India ink-injected albino rabbit eye showed the localization of dye as a black line in the suprachoroidal space. Suprachoroidal injection of NaF showed signal localization to the choroid and retina at 1 and 3 h post injection when compared with intravitreal and intracameral injections. Drug delivery to the vitreous after suprachoroidal injection decreased with an increase in solute lipophilicity and molecular weight. With an increase in drug lipophilicity, drug levels in the choroid–retinal pigment epithelium (RPE) and retina generally increased with some exceptions. Beta-blockers and FITC-dextrans were localized more to the dosed side when compared to the opposite side of the sclera, choroid–RPE, retina, and vitreous. These differences were greater for FITC-dextrans as compared to the beta-blockers. Conclusions The suprachoroidal route of injection allows localized delivery to the choroid–RPE and retina for small as well as large molecules. Suprachoroidal drug delivery to the vitreous declines with an increase in drug lipophilicity and molecular weight. Drug delivery differs between the dosed and opposite sides following suprachoroidal injection, at least up to 3 h. PMID:23734089

  9. [Studies on clinical pathophysiology of pseudophakic/aphakic eyes--a journey of 4 decades].

    PubMed

    Miyake, Kensaku

    2008-03-01

    My prime years as an ophthalmologist began as intraocular lenses (IOLs) were just entering into the developmental stage, and I took on as my mission to contribute to perfecting safe and reproducible cataract/IOL implantation surgery. Identifying surgical and/or IOL-related complications consumed time; however, these complications soon became predictable and even preventable with the use of sensitive biological parameters and preclinical evaluation. This was a simple goal for me to pursue my studies on cataract/IOL implantation surgery. I discuss in this review article, based on my previous research, clinico-pathophysiological problems of these intra- and postoperative eyes. The early phase of cataract/IOL implantation surgery development began with a debate as to which is physiologically superior: intracapsular cataract extraction (ICCE) or extracapsular cataract extraction (ECCE). From the perspective of transporting substances from intraocular fluids to extraocular space, which we studied using a nonphysiological substance, fluorescein, ECCE was confirmed to be physiologically superior to ICCE. The transport mechanism of both physiological and nonphysiological substances from intraocular fluids (such as vitreous and aqueous humor) is believed to be related to the pathogenesis of various ocular disorders. Following the fluorescein study, I next focused my attention on biosynthesis and active transport of prostaglandin (PG), which are inflammatory mediators. My studies revealed that PG were more likely to accumulate in ICCE eyes than in ECCE eyes; higher intraocular concentration of PG was also confirmed in eyes with persistent aphakic or pseudophakic cystoid macular edema (CME). While conducting the above studies and having made some observations, I postulated another hypothesis on the pathogenesis of aphakic or pseudophakic CME as follows: topical application of nonsteroidal antiinflammatory drugs (NSAIDs) to eyes with PG, which are biosynthesized intra- and postoperatively during the healing process of uveal tissues and lens epithelial cells, prevents CME. Based on this hypothesis experimental studies were then started, and in 1977 I became the first in the world to prove that topical application of indomethacin, one of the NSAIDs, controls the incidence of CME in ICCE eyes. Thereafter, some 40 follow-up studies have been conducted worldwide, and recent meta-analysis has established the efficacy of indomethacin. Macular edema and CME are recently of significant interest as complications in various ocular disorders. Compared to other forms of CME, the pathophysiology of CME associated with aphakic/ pseudophakic eyes is relatively simple, its natural history is well understood and its reproducibility is high. It is possible that the other forms of macular edema or CME having more complicated pathogenesis may be interpreted by understanding the formation mechanism of aphakia/pseudophakic CME. Our studies have shown how chemical mediators (PG) are systematically involved in the development of aphakic/pseudophakic CME, and that they concurrently cause blood-aqueous barrier disruption and CME, decrease oscillatory potential of the full field ERG, and decrease choroidal blood flow at an early postoperative period, and this has recently been proven. All these phenomena, however, can be effectively prevented by topical application of NSAIDs. I believe these findings provide significant information when considering the pathogenesis and treatment of CME associated with other ocular disorders. Using the primitive method of an early phase, I discovered that anti-PG eye drops can treat disrupted blood-aqueous barrier, and confirmed that the blood-aqueous barrier function is indeed a very sensitive function. I next applied fluorophotometry and laser flaremetry. Using blood-aqueous barrier function as a parameter, the following were evaluated: consensual reaction of blood-aqueous barrier disruption, method of IOL fixation, racial differences in disruption of the aqueous barrier function, drugs used perioperatively, biocompatibility of IOL materials, and effects of preservative agents. Research on preservative agents disclosed that the preservative agent in anti-glaucoma drops more strong by induced pseudophakic CME than the anti-glaucoma agent itself. Thus, this introduced a new concept called Our desire to closely observe the endosurface of the iris, ciliary processes and anterior vitreous face, all of which are closely related to phacoemulsification techniques, posterior chamber lens fixation, and active transport of PG, led me to the development of "Posterior video technique" (Miyake-Apple View). The technique since then has been used to evaluate cataract surgical techniques, to analyze complications, to review IOL designs and fixation techniques, to pre-clinically evaluate surgical devices, and to study variations of local anatomy related to cataract/IOL surgery. The method is also useful as an educational as well as a presentational tool, and it has now been accepted world-wide. The pathogenesis of aphakic/pseudophakic CME, physiological evaluation centering on blood-aqueous barrier function, and preclinical evaluation using the Posterior video technique have all played a significant role in establishing today's safe cataract/IOL implantation surgery.

  10. Turning calcium carbonate into a cost-effective wastewater-sorbing material by occluding waste dye.

    PubMed

    Zhao, Dan-Hua; Gao, Hong-Wen

    2010-01-01

    Over the years, organic pollution in the environment has aroused people's concern worldwide, especially persistent organic pollutants (POPs). Particularly in developing countries, plenty of concentrated organic wastewaters treated noneffectively are discharged into aquatic environments from chemical, textile, paper-making, and other industries to seriously threaten the surface and drinking water. The conventional wastewater treatment techniques are often helpless due to high cost with multilevel processing. Adsorption as an efficient method is often applied to the treatment of wastewater. The aim of this work is to develop an eco-friendly and cost-effective wastewater-sorbing material with weak acidic pink red B (APRB) and calcium carbonate (CaCO(3)) by reusing highly concentrated dye wastewater. On the basis of the chemical coprecipitation of APRB with growing CaCO(3) particles, an inclusion material was prepared. The composition of material was determined by atomic absorption spectrometry, thermogravimetric analysis, and transmission electron microscopy (TEM)-energy dispersive X-ray, and its morphology characterized by X-ray diffraction, scanning electron microscopy, TEM, and particle-size analysis. Two cationic dyes, ethyl violet (EV) and methylene blue (MB), and four POPs, phenanthrene (Phe), fluorene (Flu), biphenyl (Bip), and biphenol A (Bpa), were used to investigate the adsorption selectivity, capacity, and mechanism of the new material, where spectrophotometry, fluorophotometry, and high-performance liquid chromatography were used for determination. An APRB-producing wastewater was reused for preparing the cost-effective wastewater-sorbing material instead of the APRB reagent and then treating cationic dye wastewaters. The remove rates of colority and chemical oxygen demand (COD) were evaluated. The CO(3) (2-)-APRB-Ca(2+) addition sequence is most favorable for the occlusion of APRB into the growing CaCO(3) particles, and the occlusion of APRB corresponded to the Langmuir isothermal adsorption with the binding constant (K) of 5.24 x 10(4) M(-1) and the Gibbs free energy change (Delta G) of -26.9 kJ/mol. The molar ratio of Ca(2+) to CO(3) (2-) and APRB was calculated to be 1:0.94:0.0102, i.e., approximately 92 CaCO(3) molecules occluded only one APRB. Approximately 78% of the inclusion aggregates are between 3 and 20 mm and the particles are global-like with 50-100 nm. The element mapping on Ca, S, and C indicated APRB distributed a lot of CaCO(3), i.e., the APRB layer may be pressed between both sides of CaCO(3) layers. The molar ratio of Ca to S was calculated to 44, i.e., 88 CaCO(3) molecules carried one APRB, according to the above data. During the growing of CaCO(3) particles, APRB may be attracted into the temporary electric double layer in micelle form by the strong charge interaction between sulfonic groups of APRB and Ca(2+) and the hydrophobic stack of long alkyl chains. Four dyes were adsorbed: reactive brilliant red X-3B and weak acid green GS as anionic dyes and EV and MB as cationic dyes. The removals of EV and MB are extremely obvious and the saturation adsorption of EV and MB just neutralized all the negative charges in the inclusion particles. The selectivity demonstrated the ion-pair attraction, i.e., the cationic adsorption capacity depends on the negative charge number of the inclusion material. By fitting the Langmuir isotherm model, the monolayer adsorptions of EV and MB were confirmed. Their K values were calculated to be 2.4 x 10(6) and 7.3 x 10(5) M(-1), and Delta G was calculated to be 36.4 and -33.4 kJ/mol. The adsorption of four POPs on the material obeyed the lipid-water partition law, and their partition coefficients (K (pw)) were calculated to be 9,342 L/kg for Phe, 7,301 L/kg for Flu, 1,226 L/kg for Bip, and 870 L/kg for Bpa. The K (pw) is the direct ratio to their lipid-water partition coefficients (K (ow)) with 0.314 of slope. Besides this, a cost-effective CaCO(3)/APRB inclusion material was prepared with an APRB-producing wastewater instead of APRB reagent, and it was used in the treatment of two practical cationic dye wastewaters (samples A and B). The colority and COD in sample B are 18 and 13 times high as those of sample A. The decolorization of sample A is over 96%, and the removal of COD is between 70% and 80% when more than 0.3% adsorbent was added. However, those of sample B are over 98% and 88% in the presence of over 1% adsorbent. The adsorbent added in sample B, which was only two to three times as high as that in sample A, brought a similar removal rate of colority and COD. The inclusion material is more efficient for treatment of a highly concentrated dye wastewater because it may adsorb the most cationic dye up to saturation. A cost-effective onion-like inclusion material was synthesized with the composition ratio 90 +/- 2 of CaCO(3) to APRB, and it carried a lot of negative charges and lipophilic groups. It has a high adsorption capacity and rapid saturation for cationic dye and POPs. The adsorption of cationic dyes corresponded to the Langmuir isothermal model and that of POPs to the lipid-water partition law. The adsorbent is suitable for treatment of concentrated cationic dye and POPs wastewater in neutral media. The addition quantity of the calcium carbonate-APRB adsorbent was suggested below: only 3-5 kg per ton of wastewater (<1,000 colority or <2 mg/L POPs) and 20-30 kg per ton of highly concentrated wastewater (>20,000 colority or >50 mg/L POPs). The skeleton reactants are low-cost, easily available, and harmless to the ecological environment; additionally, the APRB reactant can reuse APRB-producing wastewater. The dye-contaminated sludge can potentially be reused as the color additive in building material and rubber and plastics industries. However, the APRB and dye contaminant would be released from the sludge when exposed to an acidic media (pH <4) for long time. This work has developed a simple, eco-friendly and practical method for the production of a cost-effective wastewater-sorbing material.

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