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Fluorescein, one of the brightest fluorescent dye molecules, is a widely used fluorophore for various applications from biomedicine to industry. The dianionic form of fluorescein is responsible for its high fluorescence quantum yield. Interestingly, the molecule was found to be nonfluorescent in the gas phase. This characteristic is attributed to the photodetachment process, which out-competes the fluorescence emission in the gas phase. In this work, we show that the calculated vertical and adiabatic detachment energies of fluorescein dianion in the gas and solvent phases account for the drastic differences observed in their fluorescence characteristics. The functional dependence of these detachment energies on the dianion's microsolvation was systematically investigated. The performance of different solvent models was also assessed. The higher thermodynamic stability of fluorescein dianion over the monoanion doublet in the solvent phase plays a crucial role in quenching photodetachment and activating the radiative channel with a high fluorescence quantum yield. [ABSTRACT FROM AUTHOR]

Synthetic Notch (SynNotch) receptors function like natural Notch proteins and can be used to install customized sense-and-respond capabilities into mammalian cells. Here, we introduce an adaptor-based strategy for regulating SynNotch activity via fluorescein isomers and analogs. Using an optimized fluorescein-binding SynNotch receptor, we describe ways to chemically control SynNotch signaling, including an approach based on a bio-orthogonal chemical ligation and a spatially controllable strategy via the photo-patterned uncaging of an o-nitrobenzyl-caged fluorescein conjugate. We further show that fluorescein-conjugated extracellular matrix (ECM)-binding peptides can be used to regulate SynNotch activity depending on the folding state of collagen-based ECM networks. To demonstrate the utility of these tools, we apply them to activate dose-dependent gene expression responses and to induce myogenic-like phenotypes in multipotent fibroblasts with spatiotemporal and microenvironmental control. Overall, we introduce an optimized fluorescein-binding SynNotch as a versatile tool for regulating transcriptional responses to ligands based on the clinically-approved fluorescein dye. Synthetic Notch (SynNotch) receptors can be used to endow cells with custom sense-and-respond capabilities. Here, the authors introduce a fluorescein-binding SynNotch as a versatile tool for controlling gene expression responses to diverse stimuli via ligands based on fluorescein-conjugates. [ABSTRACT FROM AUTHOR]

Visible light-mediated photocatalysis leads to the efficient hydrogel coating of individual mammalian cells, functionalized with biocompatible anchor molecules tagged with fluorescein serving as a trifecta: photocatalyst, initiator, and fluorophore. NIH3T3 fibroblast cells are encapsulated within hydrogel shells of poly(ethylene glycol) diacrylate (PEGDA) and N-vinylpyrrolidone without any noticeable decrease in cell viability. [ABSTRACT FROM AUTHOR]

Crayfish are emerging as model organisms for various disciplines. Moreover, decapod crustaceans also exhibit pain‐like reactions and heightened anxiety when exposed to harmful stimuli, leading to short‐term or persistent behavioral shifts. Awareness of decapod crustacean sentience and thus, suffering calls for refinement of current laboratory protocols. This study aims to enhance the standard methodology for injecting substances into crayfish by minimizing stress‐inducing manipulation. We examined the impacts of various administration routes on the persistence of injected chemicals in marbled crayfish, its excretion, and animal survival. Fluorescein dye was used as a visual marker. It was administered via three alternative injection routes—intracoelomic (IC), intrapericardial administration through areola (IP‐A), and intrapericardial administration through arthrodial membrane (IP‐AM). Continuous video observations were made for a 4‐h period under UV light, followed by intermittent observations at 12‐h intervals over 48 h. The highest mortality (20%) was observed in IP‐A administration. The IP‐A method also provided the fastest systemic distribution of the dye in the body. Results indicated visibly higher urination frequency in IP‐AM compared to IP‐A. IC mirrored IP‐AM outcomes without any observed mortality. We conclude that IC administration proved superior to intrapericardial methods, offering the least harmful but effective approach for crayfish injections. Summary: Results indicated that the administration route matters in the research of model crayfish. The IC‐administered crayfish performed better in terms of mortality, urine release, and retention time. The present study provided data beneficial for crayfish use in experimental works by identifying a proper administration route to reduce the suffering/stress to the animals without compromising the efficacy of the injected substance. [ABSTRACT FROM AUTHOR]

Purpose: To compare the anatomical and functional results of the use of Autostable-II self-retaining stent (A-II SRS) and bicanalicular silicone tube (BST) in the treatment of epiphora due to distal or common canalicular obstruction. Setting and design: This prospective, comparative, interventional study was conducted at El Minia University, Faculty of Medicine, Department of Ophthalmology. Patients and methods: This study included 80 eyes of 65 patients and was performed from March 2020 to June 2021 in Minia University Hospital. Detailed history taking, anterior segment examination, lacrimal probing, and syringing were done. The patients were evaluated 1 day, 1 week, 1 month, and 3 months postoperatively when A-II SRS and BST were removed and 3 months after their removal. Results: Eighty eyes of 56 patients with distal canalicular obstruction were evaluated in this study. Patients in group A were treated using A-II SRS (FCI), and patients in group B were treated by BST (EAGLE LABS). Results revealed a highly statistically significant difference between the two groups in epiphora grading 1 day postoperatively (P =0.013) and no significant difference between the two groups postoperatively at 1 week, 1 month, 3 months, and 6 months. Objective improvement indicated by fluorescein dye disappearance test by the end of the follow-up period revealed no significant difference between the two studied groups (P =0.39). Regarding tube position, in group A, two (5%) stents were extruded. In group B, only one (2.5%) was prolapsed and removed by the end of the first month. Conclusion: The advantage of A-II SRS set over BST intubation surgery for lacrimal canalicular obstruction is easy placement without general anesthesia. However, extra costs are needed for A-II SRS, which is an important issue in areas with low economic income. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fluorescence angiography has limitations due to rapid clearance of fluorescein. • TiO 2 nanoparticles and sodium fluorescein (NPTiO 2 -FL) were successfully conjugated. • Conjugating fluorescein with NPTiO 2 enhances fluorescence photostability. • NPTiO2-FL increases retention time in the retina, improving exam duration. • NPTiO 2 -FL are safe for the intended application. Fundus Fluorescein Angiography (FFA) has been extensively used for the identification, management, and diagnosis of various retinal and choroidal diseases, such as age-related macular degeneration, diabetic retinopathy, retinopathy of prematurity, among others. This exam enables clinicians to evaluate retinal morphology and the pathophysiology of retinal vasculature. However, adverse events, including from mild to severe reactions to sodium fluorescein, have been reported. Titanium dioxide nanoparticles (NPTiO 2) have shown significant potential in numerous biological applications. Coating or conjugating these nanoparticles with small molecules can enhance their stability, photochemical properties, and biocompatibility, as well as increase the hydrophilicity of the nanoparticles, making them more suitable for biomedical applications. This work demonstrates the potential use of ultrasmall titanium dioxide nanoparticles conjugated with sodium fluorescein to improve the quality of angiography exams. The strategy of conjugating fluorescein with NPTiO 2 successfully enhanced the fluorescence photostability of the contrast agent and increased its retention time in the retina. Preliminary in vivo and in vitro safety tests suggest that these nanoparticles are safe for the intended application demonstrating low tendency to hemolysis, and no significant changes in the retina thickness or in the electroretinography a-wave and b-wave amplitudes. Overall, the conjugation of fluorescein to NPTiO 2 has produced a nanomaterial with favorable properties for use as an innovative contrast agent in FFA examinations. By providing a clear description of our methodology of analysis, we also aim to offer better perspectives and reproducible conditions for future research. [ABSTRACT FROM AUTHOR]

Purpose: To compare the efficacy, safety, and tolerability of lifitegrast 5% versus carboxymethylcellulose (CMC) 0.5% in adult patients with dry eye disease (DED). Methods: A total of 370 eligible patients with DED were randomized equally to receive twice-daily doses of a single drop in each eye of either lifitegrast 5% or CMC 0.5% for 12 weeks. Follow-up at weeks 2, 6, and 12 evaluated changes from baseline in primary [eye dryness score (EDS), ocular discomfort score (ODS), ocular surface disease index (OSDI), and tear film break-up time (TFBUT)] and secondary [Schirmer tear test (STT) score and corneal fluorescein staining (CFS) score] endpoints. Global improvement, safety, and tolerability were also assessed. Results: At week 2, values of ocular discomfort score, OSDI, and conjunctival redness were significantly more favorable in patients treated with lifitegrast compared to CMC. At week 6, values of all study variables were better in patients treated with lifitegrast compared to CMC; differences between the groups were statistically significant for all except photophobia. This trend was also maintained at week 12. Global improvement and tolerability were found to be better with lifitegrast than with CMC. No serious safety concerns were reported in any treatment group. Conclusion: To our knowledge, this is the first active-controlled trial informing on the efficacy, safety, and tolerability of lifitegrast 5%. Significantly more favorable values for EDS (except photophobia), ODS, OSDI, TFBUT, STT score, CFS score, and conjunctival redness score were achieved at week 12 with lifitegrast 5% compared to CMC 0.5%. [ABSTRACT FROM AUTHOR]

Cellulose acetate butyrate is a biodegradable cellulose ester bioplastic produced from plentiful natural plant-based resources. Solvent-exchange-induced in situ gels are particularly promising for periodontitis therapy, as this dosage form allows for the direct delivery of high concentrations of antimicrobial agents to the localized periodontal pocket. This study developed an in situ gel for periodontitis treatment, incorporating a combination of metronidazole and doxycycline hyclate, with cellulose acetate butyrate serving as the matrix-forming agent. Consequently, assessments were conducted on the physicochemical properties, gel formation, drug permeation, drug release, morphological topography, and antimicrobial activities of the formulation. The formulation demonstrated an increased slope characteristic of Newtonian flow at higher bioplastic concentrations. The adequate polymer concentration facilitated swift phase inversion, resulting in robust, solid-like matrices. The mechanical characteristics of the transformed in situ gel typically exhibit an upward trend as the polymer concentration increased. The utilization of sodium fluorescein and Nile red as fluorescent probes effectively tracked the interfacial solvent–aqueous movement during the phase inversion of in situ gels, confirming that the cellulose acetate butyrate matrix delayed the solvent exchange process. The initial burst release of metronidazole and doxycycline hyclate was minimized, achieving a sustained release profile over 7 days in in situ gels containing 25% and 40% cellulose acetate butyrate, primarily governed by a diffusion-controlled release mechanism. Metronidazole showed higher permeation through the porcine buccal membrane, while doxycycline hyclate exhibited greater tissue accumulation, both influenced by polymer concentration. The more highly concentrated polymeric in situ gel formed a uniformly porous structure. Metronidazole and doxycycline hyclate-loaded in situ gels showed synergistic antibacterial effects against S. aureus and P. gingivalis. Over time, the more highly concentrated polymeric in situ gel showed superior retention of antibacterial efficacy due to its denser cellulose acetate butyrate matrix, which modulated drug release and enhanced synergistic effects, making it a promising injectable treatment for periodontitis, particularly against P. gingivalis. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the study was to systematically review the evidence from randomized controlled trials that evaluate the efficacy and safety of perfluorohexyloctane in the treatment of dry eye disease. Methods: Literature search was conducted on PubMed and Scopus in April 2024 with the search strategy (“perfluorohexyloctane” or “NOV03” or “semifluorinated alkane”) and “dry eye.” Extension and paired-eyes study were excluded. The risk of bias was assessed using the Cochrane risk-of-bias tool. Forest plots and a summary of findings were prepared for total corneal fluorescein staining (tCFS), tear film break-up time (TFBUT), eye dryness score (EDS), and Ocular Surface Disease Index (OSDI). Results: The pooled standardized mean difference (SMD) for tCFS after 8 weeks of treatment was −0.53 (95% CI: −0.68 to −0.38; p < 0.001), indicating a significant improvement in patients treated with perfluorohexyloctane. The between-study heterogeneity was moderately high (I2 = 52.0%). No significant differences in TFBUT were observed (SMD = 0.05; 95% CI: −0.16 to 0.25; p = 0.654). Regarding symptoms, patients treated with NOV03 had significantly lower EDS compared to controls (SMD = −0.49; 95% CI: −0.66 to −0.32; p < 0.001), with moderately high heterogeneity (I2 = 71.1%). Conversely, the pooled SMD of OSDI was −0.13 (95% CI: −0.43 to 0.17; p = 0.412), indicating no significant difference. Conclusion: Perfluorohexyloctane is an effective and safe alternative for the treatment of evaporative dry eye disease due to MGD that can significantly reduce tCFS and eye dryness symptoms. More well-designed non-sponsored randomized clinical trials are required to investigate the impact on other ocular surface parameters. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effects of rebamipide ophthalmic suspension on optical quality and efficacy of patients with dry eye under different conditions. Methods: A comprehensive search across five databases (PubMed, Cochrane Library, Web of Science, China National Knowledge Infrastructure, and Wan Fang) was conducted for studies published through May 13, 2024, focusing on rebamipide for dry eye treatment. Results: A total of 11 studies including 334 patients with dry eye were included. Tear breakup time (TBUT) values of patients with dry eye increased significantly after 2 weeks (standardized mean difference [SMD] =1.07, 95% confidence interval [CI] = [0.05, 2.09]), 4 weeks (SMD = 1.26, 95% CI = [0.77, 1.75]), and 12 weeks (SMD = 1.04, 95% CI = [0.37, 1.71]) of rebamipide treatment. Subgroup analysis revealed that patients with dry eye wearing soft contact lens (SCL) exhibited higher TBUT values after 4 weeks of rebamipide treatment compared with those who received rebamipide alone. In addition, rebamipide significantly improved fluorescein staining score of patients with dry eye after 4 weeks of treatment (SMD = −0.34, 95% CI = [−0.63, −0.06]). However, 4 weeks of rebamipide treatment showed no significant effect on Schirmer I test values (SMD = −0.04, 95%, CI = [−0.43, 0.35]) and higher-order aberrations (SMD = −0.73, 95% CI = [−1.77, 0.30]). Conclusions: These results indicate a significant improvement in the efficacy of rebamipide treatment for patients with dry eye, particularly for those wearing SCL. The effect of rebamipide on visual quality was found to correlate with the underlying dry eye status. [ABSTRACT FROM AUTHOR]

Background: Cerebrospinal Fluid (CSF) leak during endonasal endoscopic pituitary adenoma surgery is an important factor that affects the way of sellar floor closure, postoperative CSF leak rate and postoperative outcome. Our objective is to determine the rate and significance of intraoperative cerebrospinal fluid leak in endoscopic pituitary Adenoma surgery with intrathecal fluorescein administration. Methods: The study focused on 18 patients diagnosed with pituitary adenoma. These patients underwent resection through endonasal transsphenoidal approach with the use of intrathecal fluorescein injection. The rate of intraoperative CSF leak was noted and correlated with tumor size, consistency, extension, extent of resection, postoperative CSF leak and the way of closure of the sellar floor. Results: With the use of intrathecal fluorescein, intraoperative CSF leak appeared to be higher than usual. Intraoperative CSF leak occurred in 15 patients (83.3%). As regard grades of CSF leak, 11 patients had grade 1(61.1%), 3 patients had grade 2(16.7%) and only one patient had grade 3 (5.6 %). Fluorescein injection was done for patients with no CSF leak or suspicion of CSF leak but not done for grade 2 and 3, hence, it was done for 14 patients (77.8%) and in 7 of them (50%), CSF leak appeared only with Fluorescein, in 4 of them (28.5%) suspicious leak was confirmed with Fluorescein and 3 of them (21.5%) had no CSF leak confirmed with no Fluorescein appearance after injection. Postoperative CSF leak occurred in 3 of 18 patients (16.7%) and relieved in all patients after few days with lumbar drain kept in place till CSF leak stopped. Conclusion: The use of intrathecal fluorescein during endoscopic transsphenoidal pituitary surgery is very helpful in identifying intraoperative CSF leak especially G1 leak, resulting in better sellar closure and less postoperative CSF leak. [ABSTRACT FROM AUTHOR]

The objective of this research was to assess the viability and developmental potential of feline oocytes following in vitro maturation (IVM), vitrification, and post-warming incubation with resveratrol. In the first experiment, warmed oocytes were incubated with 0.2 μM, 2 μM, or 20 μM resveratrol for 2 h. Oocytes treated with 0.2 μM resveratrol had the highest viability (68.89 %), as assessed by fluorescein diacetate and ethidium bromide staining, while higher concentrations were associated with diminished oocyte viability. In the second experiment, the warmed oocytes were inseminated following the 2-h incubation with the three concentrations of resveratrol. The presumptive zygotes were then maintained in culture and their development evaluated. The highest cleavage rate was observed when the oocytes had been incubated with 0.2 μM resveratrol (88.34 %), which was higher than for the control group (without resveratrol (75 %)). Moreover, this concentration of resveratrol also augmented the blastocyst formation rate. While the vitrification of oocytes often results in diminished developmental potential in the ensuing embryos, attributed to cryopreservation-induced injury, the utilization of low concentrations of resveratrol enhances the procedure's efficacy. • Resveratrol treatment is a possible countermeasure against cryopreservation‐induced mitochondrial damage. • Resveratrol improved the viability of oocytes after vitrification. • Oocytes vitrified and incubated with resveratrol have good developmental competence after IVF. • Resveratrol improves the quality of oocytes vitrified in minimal volumes. [ABSTRACT FROM AUTHOR]

Purpose: Evaluate and compare the retention time on the canine ocular surface of crosslinked hyaluronic acid (X-HA), linear hyaluronic acid (L-HA) and saline solution using fluorescent compounds (fluorescein sodium salt, Alexa Fluor 488 cadaverine and Alexa Fluor 488 maleimide). Methods: 0.9% saline solution (SAL) was combined with fluorescein sodium salt. X-HA and L-HA were covalently modified using Alexa Fluor 488 reactive moieties. Eye drops were applied to 70 eyes of 35 dogs that were previously assessed and determined to have a normal ocular surface. Employing a blue light filter (450–490 nm), digital images were captured from instillation to 180 min. Images were analyzed to assess the percent of the total ocular area covered with green fluorescence at various time points. Results: X-HA exhibited a dual phase behavior: A broad microgel coverage first, followed by accumulation in tear film meniscus and medial canthus in the second phase, remaining in contact with the ocular surface up to 180 min. Coverage with L-HA and SAL eye drops quickly migrated to the tear meniscus. No traces of the fluorescent compounds were observed by 45 min in eyes treated with SAL solution compound and, by 120 min, eyes treated with L-HA. Conclusions: X-HA exhibited a significantly increased ocular surface contact time with the ocular surface compared with L-HA and SAL. Not only could this indicate extended lubrication time but also supports the potential use of this compound as a method for topical sustained-release drug application. [ABSTRACT FROM AUTHOR]

Sentinel lymph node biopsy is currently the gold standard for clinically node-negative patients of carcinoma breast. Fluorescein is a safe, low-cost agent, and easily available. Fluorescein has shown a promising role in sentinel lymph node evaluation in carcinoma breast in combination with methylene blue dye with a detection rate of more than 90% and a false-negative rate of less than 10% in previous studies. This study aims to determine the detection rate and diagnostic accuracy of fluorescein and methylene blue dye in early breast cancer. The identification rate and false-negative rate of the combined blue and fluorescent dye method were 100% and 7.14% respectively. The accuracy of the combined blue and fluorescein dye method was 98.3%. The sensitivity, specificity, negative predictive value, and positive predictive value of the combined blue dye and fluorescein dye method were 92.8%, 100%, 97.8%, and 100% respectively. Thus, the combined blue and fluorescein dye method is an easy, safe, cost-effective, and reliable method of sentinel lymph node biopsy in early breast cancer patients. [ABSTRACT FROM AUTHOR]

Skin microbiota plays an essential role in the development and function of the cutaneous immune system, in the maintenance of the skin barrier through the release of antimicrobial peptides, and in the metabolism of some natural products. With the aim of characterizing changes in the cutaneous microbiota specifically associated with wound healing in the diabetic condition, we performed a 16 S rRNA gene Next Generation Sequencing of skin swabs taken within the ulcer bed of ten diabetic patients before (t0) and after 20 days of therapy (t20) with a fluorescein-based galenic treatment. Considering the twenty most representative genera, we found at t20 an increase of Corynebacterium, Peptostreptococcus, and Streptococcus, and a decrease of Enterococcus, Finegoldia, and Peptoniphilus genera. However, differences were not significant due to the high variability among samples and the small patient cohort. S. aureus was the most abundant species at t0 and was reduced by therapy in four patients. Comparing the microbiome in the ulcer bed and in the perilesional tissue of the same patient at t0, no major differences were observed. Taken together, our data indicate that in the absence of antibiotic-based therapy the healing process of diabetic ulcers is accompanied by changes in the microbiome composition. [ABSTRACT FROM AUTHOR]

Although many dyes have been introduced into cellulose, whether bound to its backbone or within a cellulose matrix, few studies have determined whether the backbone statically or dynamically quenches the photoluminescence of the dye. To advance cellulosic fluorescent films, the influence of the cellulose backbone on photoluminescence must be understood. We determined the fluorescence properties of fluorescein isothiocyanate (FITC) and fluorescein-labeled cellulose (FLC) in water and alcohol, including their quantum yields , lifetimes , and rates of radiative and nonradiative decay. Dissolved FLC had a ~ 30× lower than FITC, suggesting that incorporating FITC into the cellulose backbone remarkably reduces the fluorescence efficiency. The FLC solutions had a six-fold lower than their FITC counterparts but a 10–20 times higher . Presumably, this was because the cellulose backbone interacted weakly with the fluorescein moieties, suggesting a quenching mechanism that can be termed quasi-static, corresponding to static quenching between the fluorescein moieties and cellulose backbone, in addition to the fluorescence quenching caused by the intramolecular nonradiative processes of fluorescein, as observed in conventional molecules. Using the Strickler‒Berg formula, we deduced the analytical radiative decay rate constants and eventually estimated the number of very short-lived fluorescein moieties per single fluorescent fluorescein moiety, corresponding well with static quenching. [ABSTRACT FROM AUTHOR]

The effects of pH and the solution composition on the photophysical properties of two carboxyfluorescein bifluorophores were studied along with a comparison of the fluorescence effect of these bifluorophores with that of monomer carboxyfluoresceins (5-FAM and 6-FAM) in conjugates with protein molecules. Both the bifluorophores were found to fluoresce well in an alkaline medium but the fluorescence intensity decreased at pH 6–7 and almost disappeared in acidic media. The fluorescence of meta-(6-FAM)2 is very sensitive to the solution composition, while the fluorescence of meta-(5-FAM)2 is more stable and depends only slightly on the solution properties. Upon formation of a conjugate of the bifluorophore with a protein, the fluorescence yield of the bifluorophore decreases to a greater extent in comparison with the FAM monomers but the total fluorescence yield is not less than the intensities of the two carboxyfluorescein monomer–protein conjugates due to the high extinction coefficient of the bifluorophore (~140,000 M–1·cm–1). [ABSTRACT FROM AUTHOR]

Introduction: This systematic review and meta-analysis aimed to assess the correlations of tear osmolarity (TO) with ocular symptoms and ocular surface parameters in dry eye disease (DED). Materials and methods: A literature search was conducted in PubMed, ScienceDirect, and Google Scholar databases up to 31 December 2022. Observational studies were included if they reported Pearson's-r or Spearman's-ρ of TO with ocular symptoms and/or ocular surface parameter(s) in DED patients without or with other underlying diseases. The r or ρ values were extracted and assessed using a random effect of meta-analysis. Results: Twelve studies were included in the qualitative synthesis and meta- analysis. Overall weighted summary-r values amounted to 0.17, -0.35, and -0.29 for the correlations of TO with ocular symptoms, fluorescein break-up time (FBUT), and Schirmer I, respectively. In the DED subgroup, the weighted summary-r values amounted to 0.11, -0.32, and -0.12 for the correlations of TO with ocular symptoms, FBUT, and Schirmer I, respectively. Greater weighted summary-r values were found in the autoimmune disease-related DED (AID-DED) subgroup for the correlations of TO with ocular symptoms (weighted summary-r, 0.38), FBUT (weighted summary-r, -0.39), Schirmer I (weighted summary-r, -0.47), and corneal staining (weighted summary-r, 0.38). The I2 values were 36% to 92.4%. Conclusion: This systematic review and meta-analysis reveal weak to fair correlations between TO and clinical parameters in DED, with stronger correlations in AID-DED. The findings underscore the need for standardised diagnostic methods and further research to explore the distinct mechanisms of AID-DED. Future studies should focus on longitudinal assessments, advanced diagnostic tools, and patient-centred outcomes to enhance understanding and management of DED, ultimately informing clinical guidelines and improving patient care. [ABSTRACT FROM AUTHOR]

A 73-year-old man was diagnosed with central serous chorioretinopathy (CSCR). He had atypical features including a normal indocyanine green angiography (ICG) and fundus fluorescein angiography (FFA), uncommon age group for initial diagnosis and a finding of intraretinal fluid. This case report is the first of our knowledge that exemplifies this type of unusual clinical presentation for CSCR. [ABSTRACT FROM AUTHOR]

The issue of the volume of lymphatic dissection in patients with complicated forms of colon cancer and the possibility of using methods of intraoperative visualisation of the affected lymph nodes remains controversial. The aim of the study – to analyse the results of using the intraoperative luminescent method of detecting affected lymph nodes in patients with complicated forms of malignant diseases of the large intestine. Materials and methods. The study group included 109 patients with complicated forms of colon cancer. In the gender structure, female patients predominated – 57 (52.29 %), there were 52 (47.71 %) men. The average age of the patients was 69.78 ± 16.37 years. Contrasting of regional lymph nodes was carried out using a 10 % sodium fluorescein solution. Results. According to the results of the fluorescence examination, in 67 (61.47 %) patients, lymph nodes were visualized in the regional lymphatic outflow: in 39 (58.21 %) cases, the visualized lymph nodes were located in the area of epi- and paracolic nodes (lymphodissection D1), in 23 (34.33 %) of patients – in the zone of mesocolic lymph nodes (lymphodissection D2) and in 5 (7.46 %) – in the zone of apical lymph nodes (3rd level of lymph drainage). A total of 268 lymph nodes were detected in 109 patients, which was an average of 2.46 lymph nodes per 1 patient. These nodes were marked and sent for histological examination separately from the main preparation. In total, a pathohistological examination of 1436 lymph nodes from the regional zone of lymph drainage from colon cancer was carried out, which was an average of 13.17 lymph nodes per 1 patient. Conclusions. The use of a 10 % solution of sodium fluorescein as a preparation for photoluminescence examination made it possible to visualize lymph nodes in the regional lymphatic outflow zone for the tumor in 67 (61.47 %) patients. The use of photoluminescence made it possible to determine the optimal volumes of lymphatic dissection without unjustified expansion in the case of surgical interventions for complicated forms of colon cancer. The levels of sensitivity and specificity of the photoluminescent method of detecting affected lymph nodes using a 10 % solution of sodium fluorescein had quite high results and amounted to 72.41 % and 93.28 %, respectively.

Abstract Investigating blood-brain barrier (BBB) dysfunction has become a pre-clinical and clinical research focus as it accompanies many neurological disorders. Nevertheless, knowledge of how diagnostic BBB tracers cross the endothelium from blood-to-brain or vice versa often remains incomplete. In particular, brain-to-blood transport (efflux) may reduce tracer extravasation of intravascularly (i.v.) applied tracers. Conversely, impaired efflux could mimic phenotypic extravasation. Both processes would affect conclusions on BBB properties primarily attributed to blood-to-brain leakage. Here, we specifically investigated efflux of fluorescent BBB tracers, focusing on the most common non-toxic marker, sodium fluorescein, which is applicable in patients. We used acute neocortical slices from mice and applied fluorescein, sulforhodamine-B, rhodamine-123, FITC dextran to the artificial cerebrospinal fluid. Anionic low molecular weight (MW) fluorescein and sulforhodamine-B, but not ~ 10-fold larger FITC-dextran and cationic low MW rhodamine-123, showed efflux into the lumen of blood vessels. Our data suggest that fluorescein efflux depends on organic anion transporter polypeptides (Oatp) rather than P-glycoprotein. Furthermore, sodium-potassium ATPase inhibition and incomplete oxygen-glucose deprivation (OGD, 20% O2) reduced fluorescein efflux, while complete OGD (0% O2) abolished efflux. We provide evidence for active efflux of fluorescein in vitro. Impaired efflux of fluorescein could thus contribute to the frequently observed BBB dysfunction in neuropathologies in addition to blood-to-brain leakage.

Parenchymal distribution of nebulized drug in healthy and diseased lungs has not, as evident from a literature review, been well characterized. We use a vibrating mesh nebulizer to deliver fluorescein solution in vivo to healthy or intratracheal‐lipopolysaccharide (LPS)‐instilled anesthetized rats in dorsal recumbency, or ex vivo to the lungs of LPS‐instilled rats. Following in vivo nebulization (healthy/LPS‐instilled), we quantify fluorescein intensity distribution by confocal microscopy in standard locations on the surface of freshly isolated lungs. Following LPS instillation (in vivo/ex vivo nebulization), we quantify fluorescein intensity in visibly injured locations. In standard locations, there is uniform, low‐intensity basal fluorescein deposition. Focal regions receive high deposition that is, in upper (cranial), middle, and lower (caudal) locations, 6.4 ± 4.9, 3.3 ± 3.0, and 2.3 ± 2.8 times greater, respectively, than average basal intensity. Following LPS instillation, deposition in moderately injured regions can be high or low; deposition in severely injured regions is low. Further, actively phagocytic cells are observed in healthy and LPS‐instilled lungs. And LPS particularly impairs mechanics and activates phagocytic cells in the male sex. We conclude that a low level of nebulized drug can be distributed across the parenchyma excepting to severely injured regions. [ABSTRACT FROM AUTHOR]

The document introduces the special issue "The Self-Assembly and Design of Polyfunctional Nanosystems 3.0," focusing on stimulus-responsive systems for drug release and diagnostic markers in biomedicine and cancer therapy. Various studies are highlighted, including the synthesis of pH-responsive drug nanocarriers and the development of porous nanostructures for drug delivery. The research also explores the use of supramolecular interactions in sensor development, antimicrobial agents, and gene expression vectors. Overall, the document showcases the potential of supramolecular self-assembly in creating innovative solutions for medical and ecological applications. [Extracted from the article]

We reported the regulation of macrophage polarization by iron oxide nanoparticles through conjugation with fluorescein and polyethylene glycol. When the modified nanoparticles were taken up by macrophages, the M2 phenotype was induced by upregulating anti-inflammatory markers such as CD163 and CD209, as well as associated transcripts such as IL10 and TGF-β, potentially for use as an MR contrast agent with minimal pro-inflammatory stimulation. [ABSTRACT FROM AUTHOR]

Electrochemiluminescence resonance energy transfer (ECL-RET) is a versatile signal transduction strategy widely used in the fabrication of chem/biosensors. However, this technique has not yet been applied in visualized imaging analysis of intracellular species due to the insulating nature of the cell membrane. Here, we construct a ratiometric ECL-RET analytical method for hypochlorite ions (ClO−) by ECL luminophore, with a luminol derivative (L-012) as the donor and a fluorescence probe (fluorescein hydrazide) as the acceptor. L-012 can emit a strong blue ECL signal and fluorescein hydrazide has negligible absorbance and fluorescence signal in the absence of ClO−. Thus, the ECL-RET process is turned off at this time. In the presence of ClO−, however, the closed-loop hydrazide structure in fluorescein hydrazide is opened via specific recognition with ClO−, accompanied with intensified absorbance and fluorescence signal. Thanks to the spectral overlap between the ECL spectrum of L-012 and the absorption spectrum of fluorescein, the ECL-RET effect is gradually recovered with the addition of ClO−. Furthermore, the ECL-RET system has been successfully applied to image intracellular ClO−. Although the insulating nature of the cell itself can generate a shadow ECL pattern in the cellular region, extracellular ECL emission penetrates the cell membrane and excites intracellular fluorescein generated by the reactions between fluorescein hydrazide and ClO−. The cell imaging strategy via ECL-RET circumvents the blocking of the cell membrane and enables assays of intracellular species. The importance of the ECL-RET platform lies in calibrating the fluctuation from the external environment and improving the selectivity by using fluorescent probes. Therefore, this ratiometric ECL sensor has shown broad application prospects in the identification of targets in clinical diagnosis and environmental monitoring. [ABSTRACT FROM AUTHOR]

[Display omitted] In this paper, we present a facile method of synthesis and modification of poly(glycidyl methacrylate) brushes with 6-aminofluorescein (6AF) molecules. Polymer brushes were obtained using surface-grafted atom transfer radical polymerization (SI-ATRP) and functionalized in the presence of triethylamine (TEA) acting both as a reaction catalyst and an agent preventing aggregation of chromophores. Atomic force microscopy (AFM), FTIR, X-ray photoelectron spectroscopy (XPS) were used to study the structure and formation of obtained photoactive platforms. UV-Vis absorption and emission spectroscopy and confocal microscopy were conducted to investigate photoactivity of chromophores within the macromolecular matrix. Owing to the simplicity of fabrication and good ordering of the chromophore in a thin nanometric layer, the proposed method may open new opportunities for obtaining light sensors, photovoltaic devices, or other light-harvesting systems. [ABSTRACT FROM AUTHOR]

Objective Animals Studied Procedures Results Conclusions To examine the effect of client presence on healing rates of spontaneous chronic corneal epithelial defect (SCCEDs) following debridement and anterior stromal puncture (ASP).Sixty‐eight client‐owned dogs.Dogs presenting prior to the COVID‐19 shutdown were assigned to the C group (client in the room, 31/68), while dogs presenting after were assigned to group NC (no client in the room, 37/68). Inclusion criteria were retention of fluorescein, non‐adherent epithelium, persistence for at least 1 week, and recheck within 1 month. Exclusion criteria were concurrent ocular disorders and endocrinopathies. Success was defined as negative fluorescein retention at first recheck. t‐Tests, rank‐sum tests, and chi‐squared or Fisher's exact tests were used to compare findings between groups. Logistic regression was used to determine whether odds of success at first recheck differed between groups or were modified by other characteristics.Dogs in the NC group were older (9.9 vs. 8.7 years, p = .014) and had more bandage contact lenses (BCLs) placed (65% vs. 29%, p = .003). There were no other significant differences between groups. BCL placement was associated with significantly greater odds of healing by first recheck (OR = 4.00, 95% CI: 0.63–11.2; p = .008). The NC group initially had 2.5 times greater odds of healing than the C group; after adjusting for BCL placement, the association between client location and healing weakened (aOR = 1.80, 95% CI: 0.63–5.13; p = .277).Healing was marginally associated with not having the client in the room, likely due to increased BCL use. BCL application improves SCCED healing rates following debridement/ASP. [ABSTRACT FROM AUTHOR]

Stereotactic needle biopsy stands as a crucial method for diagnosing intracranial lesions unsuitable for surgical intervention. Nonetheless, the potential for sampling errors lead to innovative approaches to enhance diagnostic precision. This study contrasts the outcomes of patients undergoing fluorescein-assisted frameless stereotactic needle biopsy with those receiving traditional biopsies to evaluate the impact on diagnostic accuracy and safety. This study included patients with contrast-enhancing intracranial lesions, comprising a prospective group undergoing fluorescein-assisted biopsies and a retrospective group undergoing conventional biopsies at the same institution. We've collected data on demographics, procedural specifics, diagnostic outcomes, and postoperative events. A comparative analysis involved 43 patients who received fluorescein-assisted biopsies against 77 patients who underwent conventional biopsies. The average age was 60.5 years. The fluorescein group exhibited a 93% success rate in diagnosis, markedly higher than the 70.1% in the non-fluorescein group (OR = 5.67; 95%IC: 1.59–20.24; p < 0.01). The rate of complications was statistically similar across both cohorts. Despite its established value, stereotactic needle biopsy is susceptible to inaccuracies and complications. The application of fluorescence-based adjuncts like 5-ALA and fluorescein has been investigated to improve diagnostic fidelity and reduce risks. These technologies potentially minimize the necessity for multiple biopsies, decrease surgical duration, and provide immediate verification of tumor presence. Fluorescein-assisted stereotactic biopsy emerges as an effective, secure alternative to conventional methods. [ABSTRACT FROM AUTHOR]

Aim: To study parasitic eye diseases in a tertiary institute of North-east India by live examination of parasites, rapid staining, and scanning electron microscopy (SEM). Methods: A 12-year retrospective analysis was performed and all patients diagnosed with ocular parasitic diseases were identified. Examination under a compound microscope, fluorescein staining, and scanning electron microscopy were done. Results: A total of 160 ocular parasitosis cases were identified. The cases for which rapid staining and SEM studies were done included Cysticercosis (n = 18, 11.25%), Hydatidosis (n = 5, 3.13%), Dirofilariasis (n = 5, 3.13%), Thelaziasis (n = 3, 1.87%), and Gnathostomiasis (n = 2, 1.25%). Live examination was performed in 11 cases (6.63%) and 8 cases (4.82%) underwent scanning electron microscopy. Conclusion: Fluorescein staining for identification of parasites and SEM study helped in detailing microscopic and ultrastructural findings. [ABSTRACT FROM AUTHOR]

MoO3-x NPs was rapidly synthesized at room temperature by an easy stirring method. It was interesting to find that MoO3-x NPs induce OH− to generate active free radicals (ROS), which is a highly promising property in chemiluminescence (CL). Benefiting from the abundant oxygen vacancy, MoO3-x NPs adsorbs H2O2 and turn it into ·OH. The oxidase activity of fluorescein under visible light had already been reported, which catalyzes dissolved oxygen to become O2−· and continue to convert to H2O2. By creating the synergy effect with fluorescein, MoO3-x NPs strengthen the CL intensity of K3[Fe(CN)6]-fluorescein system significantly. Utilizing the quench effect of uric acid for the CL intensity, we developed a rapid, simple, and highly sensitive CL platform for uric acid detection. The linear range was 5–80 µM and the detection limit (LOD) for uric acid was 3.11 µM (S/N = 3). This work expanded the application of MoO3-x NPs in the CL field and developed a simple and highly sensitive CL sensing system to detect UA in human saliva. [ABSTRACT FROM AUTHOR]

Formulations designed to address ocular conditions and diseases are predominantly administered topically. While in vitro test systems have been developed to assess corneal permeation under extended contact conditions, methods focusing on determining the penetration depth and kinetics of a substance within the cornea itself rather than through it, are scarce. This study introduces a method for time-dependent penetration depth analysis (10 and 60 min) by means of a semiquantitative imaging method in comparison with a quantitative corneal depth-cut technique, employing fluorescein sodium at concentrations of 0.2 and 0.4 mg/mL as a small molecule model substance and sheep cornea as a human surrogate. Excised tissues exhibited sustained viability in modified artificial aqueous humor and maintained thickness (746 ± 43 µm) and integrity (electrical resistance 488 ± 218 Ω∙cm2) under the experimental conditions. Both methods effectively demonstrated the expected concentration- and time-dependent depth of penetration of fluorescein sodium, displaying a significantly strong correlation. The traceability of the kinetic processes was validated with polysorbate 80, which acted as a penetration enhancer. Furthermore, the imaging-based method enabled detecting the retention of larger structures, such as hyaluronic acid and nanoemulsions from the commercial eyedrop formulation NEOVIS® TOTAL multi, inside the lacrimal layer. [ABSTRACT FROM AUTHOR]

A method for the synthesis of a nanostructured turpentine oil lyosol by bubbling an emulsion of turpentine oil in water with air in a mass ratio of 1:200 to 1:2200 by the separation of nanoparticles using nanofiltration has been proposed. Changing the mass ratio of turpentine oil to the aqueous phase during the synthesis was shown to influence the size of the resulting nanoparticles. An increase in the Z-average size of nanoparticles from 50 to 320 nm along with a gradual decreasing turpentine content from 1:200 to 1:1000 was observed. A further decrease in the turpentine load from 1:1000 to 1:2200 led to decreasing the Z-average particle size up to 160 nm. The fact of the formation of stable non-covalent complexes of the lyosol particles with fluorescein has been established. The fluorescein-stained lyosol particles were used to study the efficiency of their phagocytosis by chicken blood monocytes using confocal microscopy. The maximum efficiency of the lyosol phagocytosis by the chicken monocytes was observed when the Z-average lyosol particle size was ~ 50 nm, which was achieved with a turpentine dry matter ratio of 1:200 during the synthesis. [ABSTRACT FROM AUTHOR]

Simple Summary: This study explores the use of fluorescence-guided resection in glioblastoma surgery, focusing on the combined use of 5-aminolevulinic acid and sodium fluorescein. By analyzing 100 cases from our medical center, we aimed to address concerns about fluorescence-guided resection and share our findings. The dual use of 5-aminolevulinic acid and fluorescein enhances the extent of tumor resection and reduces false positives without increasing adverse effects. In our experience, fluorescein guided the initial resection phase, while 5-aminolevulinic acid identified tumor spots within the surgical cavity, achieving gross total resection in 96% of cases and supra-maximal resection in 11%. This combined approach appears promising for improving outcomes in glioblastoma patients. Background: Fluorescence-guided resection (FGR) of glioblastomas has been previously explored with the use of 5-amivelulinic acid (5-ALA) and sodium fluoresceine (SF), allowing us to maximize the extent of resection (EoR). In this study, we highlight the most relevant concerns regarding this technique and present the methods and results from the experience of our center. Methods: A case series of 100 patients operated on in AOU Città della Salute e della Scienza in Turin with a histological diagnosis of glioblastoma (grade IV, according to WHO 2021) was retrospectively analyzed. Both 5-ALA and SF were administered and intraoperatively assessed with an optical microscope. Results: 5-ALA is the only approved drug for FGR in glioblastoma, reporting an increased EoR. Nevertheless, SF can be positively used in addition to 5-ALA to reduce the risk of false positives without increasing the rate of adverse effects. In our experience, SF was used to guide the initial phase of resection while 5-ALA was used to visualize tumor spots within the surgical cavity. In 96% of cases, gross total resection was achieved, with supra-maximal resection in 11% of cases. Conclusions: Combined FGR using 5-ALA and SF seems to be a promising method of increasing the extent of resection and to improving the prognosis in glioblastoma patients. [ABSTRACT FROM AUTHOR]

Purpose: Brain metastases (BM) often leave residual tumors despite having visible margins, which increases the risk of local tumor recurrence and can impact overall patient survival rates. Fluorescence-guided surgery (FGS) utilizing sodium fluorescein (FL) has been reported as an effective technique in recent studies. This study aimed to evaluate the efficacy of FL FGS in improving the extent of resection of brain metastases and its impact on overall survival. Methods: We conducted a systematic search following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Our primary focus was on gross total resection (GTR). Additionally, we extracted survival data and evaluated the risk of bias using a modified version of the Joanna Briggs Institute critical appraisal tool. Results: The study comprised 970 patients with brain metastases through eight different studies. The study found that patients who underwent FL-guided resection had a significantly higher rate of GTR (OR: 2.02, 95% CI: 1.14–3.56, p = 0.0156, I2 = 41.5%). Additionally, the study concluded that FL-guided resection is associated with better overall survival rates (HR: 0.61, 95%CI: 0.47 0.80, p = 0.0003, I2 = 41.5%). Conclusion: Our research suggests that the use of FL is associated with a higher rate of GTR and improved overall patient survival. None of the studies we reviewed reported significant complications associated with the use of FL in patients. [ABSTRACT FROM AUTHOR]

Background: Xanthenes and multi-aryl carbon core containing compounds represent different types of complex and condensed architectures that have impressive wide range of pharmacological, industrial and synthetic applications. Moreover, indoles as building blocks were only found in naturally occurring metabolites with di-aryl carbon cores and in chemically synthesized tri-aryl carbon core containing compounds. Up to date, rare xanthenes with indole bearing multicaryl carbon core have been reported in natural or synthetic products. The underlying mechanism of fluorescein-like arthrocolins with tetra-arylmethyl core were synthesized in an engineered Escherichia coli fed with toluquinol remained unclear. Results: In this study, the Keio collection of single gene knockout strains of 3901 mutants of E. coli BW25113, together with 14 distinct E. coli strains, was applied to explore the origins of endogenous building blocks and the biogenesis for arthrocolin assemblage. Deficiency in bacterial respiratory and aromatic compound degradation genes ubiX, cydB, sucA and ssuE inhibited the mutant growth fed with toluquinol. Metabolomics of the cultures of 3897 mutants revealed that only disruption of tnaA involving in transforming tryptophan to indole, resulted in absence of arthrocolins. Further media optimization, thermal cell killing and cell free analysis indicated that a non-enzyme reaction was involved in the arthrocolin biosynthesis in E. coli. Evaluation of redox potentials and free radicals suggested that an oxygen-mediated free radical reaction was responsible for arthrocolins formation in E. coli. Regulation of oxygen combined with distinct phenol derivatives as inducer, 31 arylmethyl core containing metabolites including 13 new and 8 biological active, were isolated and characterized. Among them, novel arthrocolins with p-hydroxylbenzene ring from tyrosine were achieved through large scale of aerobic fermentation and elucidated x-ray diffraction analysis. Moreover, most of the known compounds in this study were for the first time synthesized in a microbe instead of chemical synthesis. Through feeding the rat with toluquinol after colonizing the intestines of rat with E. coli, arthrocolins also appeared in the rat blood. Conclusion: Our findings provide a mechanistic insight into in vivo synthesis of complex and condensed arthrocolins induced by simple phenols and exploits a quinol based method to generate endogenous aromatic building blocks, as well as a methylidene unit, for the bacteria-facilitated synthesis of multiarylmethanes. [ABSTRACT FROM AUTHOR]

The main causes for cerebrospinal fluid (CSF) leaks are known to be traumatic, iatrogenic, neoplastic, a meningoencephalocele, congenital bone defects, and spontaneous. Off-label intrathecal administration of fluorescein is widely used to localize a CSF leak. Complications are rare and low dose administration is described to be safe. In this case report, we present a case of a patient, who showed a CSF leak due to an encephalocele. Low dose fluorescein was applied intrathecally via lumbar catheter, the CSF leaks could be identified, and multilayered closure was performed. Postoperatively, the patient presented with motor and sensory deficits in the lower limbs which regressed only partially within 2 months. A possible explanation may be an increased local concentration of fluorescein, possibly on the basis of a preexisting lumbar spinal canal stenosis. To our knowledge, this is the first case in which a dose as low as 20 mg of fluorescein (2% saline mixture) led to persisting paraplegia. Therefore, the potential benefits and risks of the intrathecal fluorescein use in the detection of a CSF leak have to be discussed comprehensively prior to surgery. [ABSTRACT FROM AUTHOR]

Resection of high-grade glioma with sodium fluorescein can improve the resection rate of the glioma and improve survival. However, it is unclear whether the yellow fluorescence boundary of the high-grade glioma is consistent with the actual boundary of the tumor. This study explores the yellow fluorescence boundary and the actual tumor boundary in high-grade glioma surgery. This is a retrospective analysis of 10 patients with high-grade gliomas who underwent tumor visualization with sodium fluorescein. After staining of the tumor, random selections of both developed and non-developed yellow fluorescent border tissue at the fluorescence chromogenic boundary were made, followed by pathological examination. Claudin-5, an important component of the tight connections between vascular endothelial cells, was assessed by immunohistochemistry and qRT-PCR in the tumor and surrounding tissues in order to determine the tumor cell content of the tissue, blood-brain barrier damage, and vascular proliferation. The yellow fluorescence boundary was compared with the actual tumor boundary and the results analyzed. Tumor cells were still detected outside the yellow fluorescence boundary during high-grade glioma surgery (P < 0.05). Claudin-5 expression was higher in high-grade gliomas than in adjacent normal tissues (P < 0.05), while disconnected Claudin-5 expression was associated with intraoperative yellow fluorescence imaging (r = 0.67). There is a difference between the yellow fluorescence boundary and the actual boundary of the tumor in high-grade glioma, and there are glioma cell infiltrations in the brain tissue of the undeveloped yellow fluorescent border. To ensure patient recovery and function, it is recommended that tumor resection be expanded based on yellow fluorescence visualization. Claudin-5 is overall up-regulated in high-grade gliomas, but some Claudin-5 expression is disconnected. This Claudin-5 expression pattern may be related to the development of yellow fluorescence. [ABSTRACT FROM AUTHOR]

Background: To compare retention times of various ophthalmic viscosurgical devices (OVDs) and soft‐shell combinations. Methods: Experimental study. Eighteen rabbit eyes were divided into six groups of three eyes, based on OVDs tested. A: Endocoat, B: HealonPro, C: Viscoat, D: Provisc, E: Endocoat and HealonPro and F: Viscoat and Provisc. OVDs were stained with 10% fluorescein dye before being injected into the anterior chamber. Phacoemulsification, using fixed parameters, was performed. If OVD persisted after 60 s, a standardised irrigation and aspiration technique replaced phacoemulsification. The time until central and complete clearance of the OVD were video‐recorded and measured. Results: Mean central retention times (CRT) were found to be: HealonPro—5.33 ± 2.56 s, Provisc—3.33 ± 1.11 s, Endocoat—75.0 ± 3.26 s, Viscoat—62.33 ± 5.19 s, combining HealonPro with Endocoat—22.67 ± 4.75 s and Provisc with Viscoat—11.0 ± 0.82 s. The mean total retention time (TRT) was: Endocoat—80.0 ± 8.17 s, Viscoat—81.67 ± 2.09 s, HealonPro with Endocoat—81.33 ± 3.35 s, and Provisc with Viscoat—71.0 ± 2.94 s. For HealonPro and Provisc, CRT and TRT remained identical across all trials. Conclusions: Retention times varied, with cohesive OVDs exhibiting shorter durations than dispersive OVDs. Among dispersive OVDs, TRTs were comparable; however, Endocoat displayed an extended CRT. In soft shell trials, the combination of HealonPro and Endocoat exhibited prolonged CRT and TRT, suggesting enhanced corneal protection. [ABSTRACT FROM AUTHOR]

Metal-assisted molecular self-assembly finds applications in optoelectronics, chemical sensing and catalysis. In this article, fluorescein based polynorbornene is synthesized and its molecular self-assembly is used to detect the presence of copper(II) ions in environmental water samples (pond waters). First of all, the sequential procedures of the synthesis of norbornene and polynorbornene are accomplished using simple organic compounds available in the Indian market. Various intermediate compounds and norbornene are characterized by ¹H NMR and 13C NMR techniques. Structure of polynorbornene is proved by ¹H NMR spectroscope. Molecular weight of polynorbornene is obtained using Acquity advanced polymer chromatography. Particle size of polymer nano-aggregates is derived by using FESEM microscope. This polynorbornene (PNor-Flu) is used for the selective and sensitive detection of the copper(II) ions with an excellent LOD of 0.27 μM, far below the limit decided by the Environmental Protection Agency (EPA) of USA. This is achieved with the help of UV-Vis studies and spectroscopic titrations using OD416/OD350. As far the self-assembly is concerned using microscopic analysis, polynorbornene with a higher number of hydroxyl groups shows rod-like self-assembly. Polynorbornene structure is again transformed to a spherical shape in the presence of the copper(II) ions even in micromolar concentration. From this change, it is believed that the poynorbornene has a high potentiality for sensing the copper(II) ions, which helps it to impart unique morphological properties. From the tests performed on real water samples, polynorbornene has proved its high efficiency of selective and sensitive detective power for detecting copper(II) ions in pond waters. [ABSTRACT FROM AUTHOR]