Uveal melanoma is one of the most common and aggressive intraocular malignancies, and, due to its great capability of metastasize, it constitutes the most incident intraocular tumor in adults. However, to date there is no effective treatment since achieving the inner ocular tissues still constitutes one of the greatest challenges in actual medicine, because of the complex structure and barriers. Uncoated and PEGylated nanostructured lipid carriers were developed to achieve physico-chemical properties (mean particle size, homogeneity, zeta potential, pH and osmolality) compatible for the ophthalmic administration of (S)-(-)-MRJF22, a new custom-synthetized prodrug for the potential treatment of uveal melanoma. The colloidal physical stability was investigated at different temperatures by Turbiscan® Ageing Station. Morphology analysis and mucoadhesive studies highlighted the presence of small particles suitable to be topically administered on the ocular surface. In vitro release studies performed using Franz diffusion cells demonstrated that the systems were able to provide a slow and prolonged prodrug release. In vitro cytotoxicity test on Human Corneal Epithelium and Human Uveal Melanoma cell lines and Hen\'s egg-chorioallantoic membrane test showed a dose-dependent cytotoxic effect of the free prodrug on corneal cells, whose cytocompatibility improved when encapsulated into nanoparticles, as also confirmed by in vivo studies on New Zealand albino rabbits. Antiangiogenic capability and preventive anti-inflammatory properties were also investigated on embryonated eggs and rabbits, respectively. Furthermore, preliminary in vivo biodistribution images of fluorescent nanoparticles after topical instillation in rabbits\' eyes, suggested their ability to reach the posterior segment of the eye, as a promising strategy for the treatment of choroidal uveal melanoma.

BACKGROUND: Allergic conjunctivitis is one of the most common eye disorders. Different drugs are used for its treatment. Hesperidin is an active substance isolated from Citrus sinensis L. (Rutaceae) fruit peels, with known anti-inflammatory activity but low solubility. It was complexed with cyclodextrin and encapsulated in situ gel to extend its duration in the eye.
RESULTS: The optimized formulation comprised 1% hesperidin, 1.5% hydroxyethyl cellulose, and 16% poloxamer 407. The viscosity at 25 °C was 492 ± 82 cP, and at 35 °C it was 8875 ± 248 cP, the pH was 7.01 ± 0.03, gelation temperature was 34 ± 1.3 °C, and gelation time was 33 ± 1.2 s. There was a 66% in vitro release in the initial 2 h, with a burst effect. A lipoxygenase (LOX) inhibition test determined that hesperidin was active at high doses on leukotyrens seen in the body in allergic diseases. In cell-culture studies, the hesperidin cyclodextrin complex loaded in situ gel, BRN9-CD (poloxamer 16%, hydroxy ethyl cellulose (HEC) 1.5%), enhanced cell viability in comparison with the hesperidin solution. It was determined that BRN9-CD did not cause any irritation in the ocular tissues in the Draize test.
CONCLUSIONS: The findings of this study demonstrate the potential of the in situ gel formulation of hesperidin in terms of ease of application and residence time on the ocular surface. Due to its notable LOX inhibition activity and positive outcomes in the in vivo Draize test, it appears promising for incorporation into pharmaceutical formulations. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

UNASSIGNED: In the current research, lornoxicam-loaded in situ gels were developed, and their potential usage in ocular inflammation was evaluated.
UNASSIGNED: Lornoxicam cyclodextrin complex prepared with hydroxypropyl methylcellulose and poloxamer P407 because of the low viscosity of in situ gels to provide easy application. However, washing and removing it from the ocular surface becomes difficult due to the gelation formation with heat.
UNASSIGNED: A three-level factorial experimental design was used to evaluate the effects of poloxamer 407 concentration, polymer type, and polymer concentration on viscosity, pH, gelation capacity, gelation time, and gelation temperature, which were considered the optimal indicators of lornoxicam-containing formulations.
UNASSIGNED: As a result of the three-level factorial experimental design, the optimized formulation contained 15 (%w/v) poloxamer 407 and 1 (%w/v) hydroxypropyl methylcellulose. The optimize formulation viscosity 25 °C = 504 ± 49cP, viscosity 35 °C = 11247 ± 214cP, pH = 6.80 ± 0.01, gelation temprature = 35 ± 0.2 °C, and gelation time= 34 ± 0.2 s was obtained. In the in vitro release studies, 68% of lornoxicam was released with a burst effect in the first three hours; then, the release continued for eight hours with controlled release. Release kinetics of the formulations were modeled mathematically, and it was found to be compatible with the Korsemeyer-Peppas and Weibull models. In cell culture studies, cell viability at 100 µg/mL was 83% and 96% for NL6 and NL6-CD, respectively. In Draize\'s in vivo test, no negative conditions occurred in rats.
UNASSIGNED: Therefore, the NL6-CD formulation has the potential to be a favorable option for treating ocular inflammation.

The most prevalent conditions among ocular surgery and COVID-19 patients are fungal eye infections, which may cause inflammation and dry eye, and may cause ocular morbidity. Amphotericin-B eye drops are commonly used in the treatment of ocular fungal infections. Lactoferrin is an iron-binding glycoprotein with broad-spectrum antimicrobial activity and is used for the treatment of dry eye, conjunctivitis, and ocular inflammation. However, poor aqueous stability and excessive nasolacrimal duct draining impede these agens\' efficiency. The aim of this study was to examine the effect of Amphotericin-B, as an antifungal against Candida albicans, Fusarium, and Aspergillus flavus, and Lactoferrin, as an anti-inflammatory and anti-dry eye, when co-loaded in triblock polymers PLGA-PEG-PEI nanoparticles embedded in P188-P407 ophthalmic thermosensitive gel. The nanoparticles were prepared by a double emulsion solvent evaporation method. The optimized formula showed particle size (177.0 ± 0.3 nm), poly-dispersity index (0.011 ± 0.01), zeta-potential (31.9 ± 0.3 mV), and entrapment% (90.9 ± 0.5) with improved ex-vivo pharmacokinetic parameters and ex-vivo trans-corneal penetrability, compared with drug solution. Confocal laser scanning revealed valuable penetration of fluoro-labeled nanoparticles. Irritation tests (Draize Test), Atomic force microscopy, cell culture and animal tests including histopathological analysis revealed superiority of the nanoparticles in reducing signs of inflammation and eradication of fungal infection in rabbits, without causing any damage to rabbit eyeballs. The nanoparticles exhibited favorable pharmacodynamic features with sustained release profile, and is neither cytotoxic nor irritating in-vitro or in-vivo. The developed formulation might provide a new and safe nanotechnology for treating eye problems, like inflammation and fungal infections.

Loratadine (LORA), is a topical antihistamine utilized in the treatment of ocular symptoms of COVID-19. The study aimed to develop a Loratadine Nanostructured Lipid Carriers Ocugel (LORA-NLCs Ocugel), enhance its solubility, trans-corneal penetrability, and bioavailability. full-factorial design was established with 24 trials to investigate the impact of several variables upon NLCs properties. LORA-NLCs were fabricated by using hot melt emulsification combined with high-speed stirring and ultrasonication methods. All obtained formulae were assessed in terms of percent of entrapment efficiency (EE%), size of the particle (PS), zeta potential (ZP), as well as in-vitro release. Via using Design Expert® software the optimum formula was selected, characterized using FTIR, Raman spectroscopy, and stability studies. Gel-based of optimized LORA-NLCs was prepared using 4% HPMC k100m which was further evaluated in terms of physicochemical properties, Ex-vivo, and In-vivo studies. The optimized LORA-NLCs, comprising Compritol 888 ATO®, Labrasol®, and Span® 60 showed EE% of 95.78 ± 0.67%, PS of 156.11 ± 0.54 nm, ZP of -40.10 ± 0.55 Mv, and Qh6% of 99.67 ± 1.09%, respectively. Additionally, it illustrated a spherical morphology and compatibility of LORA with other excipients. Consequently, gel-based on optimized LORA-NLCs showed pH (7.11 ± 0.52), drug content (98.62%± 1.31%), viscosity 2736 cp, and Q12% (90.49 ± 1.32%). LORA-NLCs and LORA-NLCs Ocugel exhibited higher ex-vivo trans-corneal penetrability compared with the aqueous drug dispersion. Confocal laser scanning showed valuable penetration of fluoro-labeled optimized formula and LORA-NLCs Ocugel through corneal. The optimized formula was subjected to an ocular irritation test (Draize Test) that showed the absence of any signs of inflammation in rabbits, and histological analysis showed no effect or damage to rabbit eyeballs. Cmax and the AUC0-24 were higher in LORA-NLCs Ocugel compared with pure Lora dispersion-loaded gel The research findings confirmed that NLCs could enhance solubility, trans-corneal penetrability, and the bioavailability of LORA.

UNASSIGNED: Fluconazole is an effective anti-fungal drug. Due to the limitations of fluconazole, such as poor water solubility and consequently low ocular bioavailability, an optimized fluconazole nanoemulsion in-situ gel formulation (temperature-sensitive) was developed.
UNASSIGNED: To verify formulation\'s safety for ophthalmic use, preparation was tested for potential ocular toxicity using a cell viability assay on retinal cells. The hen\'s egg test-chorioallantoic membrane (HET-CAM), as a borderline test between in vivo and in vitro techniques, was chosen for investigating the irritation potential of the formulation. HET-CAM test was done by adding the formulation directly to the CAM surface and monitoring the vessels visually in terms of irritation reactions. Eye tolerance was determined using the modified Draize test.
UNASSIGNED: Viability assay on retinal cells displayed that fluconazole nanoemulsion in-situ gel formulation was non-toxic and can be safely used in the eye at concentrations of 0.1% and 0.5%. HET-CAM and Draize tests revealed that optimized formulation of fluconazole did not result in any irritation and was considered non-irritant and well-tolerated for ocular use.
UNASSIGNED: Regarding to the findings of the three mentioned methods, fluconazole nanoemulsion in-situ gel formulation is harmless and as a proper and safe alternative, can be considered for ocular delivery of fluconazole in the future.

The animal-based Draize test remains the gold standard for assessment of ocular irritation. However, subjective scoring methods, species differences, and animal welfare concerns have spurred development of alternative test methods. In this study, a novel in vitro method for assessing ocular irritancy was developed using a microelectric cell sensing technology, real-time cell analysis (RTCA). The cytotoxicity of sixteen compounds was assessed in two cell lines: ARPE-19 (human retina) and SIRC (rabbit cornea). In vitro inhibitory (IC50 and AUC50) values were determined at 6, 12, 24, 48, 72, and 96 h exposure, with a subset of values confirmed with MTT testing. The values displayed comparable predictivity of in vivo ocular irritation on the basis of a linear regression between the calculated values and each compounds\' corresponding Draize-determined modified maximum average score (MMAS), but the ARPE-19 derived values were more strongly correlated than those from SIRC cells. Hence, IC50 values derived from ARPE-19 cells were used to predict the UN GHS/EU CLP classification of each test compound. The method was determined to have sensitivity of 90%, specificity of 50%, and overall concordance of 75%. Thus, RTCA testing may be best incorporated into a top-down tiered testing strategy for identification of ocular irritants in vitro.

Eye irritation predictions are very important in the development of cosmetics and pharmaceuticals. For animal protection, alternative tests are being developed to replace the Draize test, which involves the use of rabbits to test eye irritation. The Vitrigel-eye irritancy test (Vitrigel-EIT), is one such alternative. As a preliminary study, we evaluated if Hansen solubility parameter (HSP) values can be used to predict Vitrigel-EIT results. An Hansen sphere was created based on the HSP values and Vitrigel-EIT results from 61 substances. Substances inside and outside of the sphere were designated as dangerous and safe substances, respectively. The safety of each test substance was predicted by comparing the center point (Ro) of the sphere with the relative energy difference, i.e., the ratio of each test substance (Ra). The accuracy, false negativity, and false positivity of the \"irritant\" and \"nonirritant\" designations, as determined by the Vitrigel-EIT results and Hansen sphere, were 91.8% (56/61), 2.3% (1/43), and 22.2% (4/18), respectively. These results indicated that HSP values can be used to predict Vitrigel-EIT results with high reproducibility, and thus are useful for evaluating the safety of substances.

Concerns regarding animal welfare have led to the need for alternatives to animal eye irritation tests. The reconstructed human cornea-like epithelium (RhCE) test is described in the OECD TG 492 as an alternative to animal eye irritation tests. However, the accuracy and labor investment of this method can be improved if the results can be predicted before the experiment. In this study, we evaluated whether Hansen solubility parameter (HSP) values can be used to predict the results of RhCE method using the LabCyte CORNEA-MODEL for 65 test substances. We found that HSP values can predict the RhCE method with high correlation (accuracy 84.6% (55/65), false-negative rate of 16.2% (7/43), and false-positive rate of 13.6% (3/22). These results indicate that HSP values can be used to predict the results RhCE method using LabCyte CORNEA-MODEL with high reproducibility, and thus are useful for evaluating the safety of substances.

The present study was focused on investigating niosomal gels loaded with cholinergic drug; pilocarpine HCl, for prolonged precorneal residence time and improved bioavailability for glaucoma treatment. Pilocarpine HCl niosomes were prepared using various nonionic surfactants (span 20, span 60 and span 80), in the presence of cholesterol in different molar ratios by ether injection method. The selected formulations were incorporated into carbopol 934 and locust bean gum-based gels. TEM analysis confirmed that niosomes formed were spherical in shape and has a definite internal aqueous space with uniform particle size. Formulation F4 composed of span 60 and cholesterol (1:1) gave the highest entrapment (93.26 ± 1.75%) and slower release results after 8 hours (Q8h = 60.35 ± 1.87%) among other formulations. The in-vitro drug permeation studies showed that there was a prolonged release of drug from niosomal gels as compared to niosomes itself. Considering the in-vitro drug release, niosomal gel formulation G2 was the best among the studied formulations. The release data were fitted to an empirical equation, which indicated that the release follows non-Fickian diffusion mechanism. The stability study revealed that incorporation of niosomes in gel increased their stability than the niosome itself. No signs of redness, inflammation, swelling or increased tear production were observed over the study period for tested formulation by Draize\'s test. The intraocular pressure (IOP) lowering activity of G2 formulation showed relative bioavailability 2.64 times more than bioavailability of marketed Pilopine HS® gel. These results suggest that the niosomal gels containing pilocarpine HCl are promising ocular carriers for glaucoma treatment.