Ocular Drug Research Articles

Design of molecularly imprinted alginate microgels for topical release of insulin

In this work, pH-sensitive molecularly imprinted (MIP) microgels are developed based on alginate for topical insulin delivery and ocular disease treatment. MIP microgels were synthesized via the emulsification-gelation method with uniform size distribution (9–11 µm) and rough surface structure. Moreover, the impact of insulin concentration, adsorption time, and pH of the drug solution on the adsorption capacity of MIP microgels was studied. Increasing the initial insulin concentration showed enhanced MIP microgel adsorption capacity at pH 5.4, while kinetic analysis revealed insulin binding after 1 h. The kinetics of insulin release at pH 6.4 (normal eye) and 7.4 (dry eye) demonstrated a good fit with the Korsmeyer–Peppas model, indicating controlled drug release. The pH-sensitive MIPs resulted in slower insulin release at pH 6.4 with ∼60% of the drug released within 1 h and reaching 80% after 8 h. In contrast, a higher insulin release rate was observed at pH 7.4 (∼ 80% after 8 h). MIP microgels showed selective adsorption toward the template molecule measured by imprinting factors about 0.60 ± 0.03 and 1.44 ± 0.21 for bovine serum albumin (BSA) and insulin, respectively. The mucoadhesive strength of MIP and NIP microgels, assessed by adsorbing them onto cow mucin, exhibited excellent performance, with values of 82±3% and 91±2%, respectively. In summary, the MIP microgels show sustained, and controlled drug delivery and are good candidates for ocular tissue drug delivery.

Moxifloxacin-loaded nanoparticles of thiolated xyloglucan for ocular drug delivery: Permeation, mucoadhesion and pharmacokinetic evaluation

The current study goal was to improve mucoadhesive potential and ocular pharmacokinetics of nanoparticles of thiolated xyloglucan (TXGN) containing moxifloxacin (MXF). Thiolation of xyloglucan (XGN) was achieved with esterification with 3-mercaptopropionic acid. TXGN was characterized by NMR and FTIR analysis. The nanoparticles of TXGN were prepared using ionic-gelation method and evaluate the antibacterial properties. TXGN and nanoparticles were determined to possess 0.06 and 0.08 mmol of thiol groups/mg of polymer by Ellman's method. The ex-vivo bioadhesion time of TXGN and nanoparticles was higher than XGN in a comparative assessment of their mucoadhesive properties. The creation of a disulfide link between mucus and TXGN is responsible for the enhanced mucoadhesive properties of TXGN (1-fold) and nanoparticles (2-fold) over XGN. Improved MXF penetration in nanoparticulate formulation (80 %) based on TXGN was demonstrated in an ex-vivo permeation research utilizing rabbit cornea. Dissolution study showed 95 % release of MXF from nanoparticles. SEM images of nanoparticles showed spherical shape and cell viability assay showed nontoxic behavior when tested on RPE cell line. Antibacterial analysis revealed a zone of inhibition of 31.5 ± 0.5 mm for MXF, while NXM3 exhibited an expanded zone of 35.5 ± 0.4 mm (p < 0.001). In conclusion, thiolation of XGN improves its bioadhesion, permeation, ocular-retention and pharmacokinetics of MXF.

Combination of PEGylation and Cationization on Phospholipid-Coated Cyclosporine Nanosuspensions for Enhanced Ocular Drug Delivery.

Strong precorneal clearance mechanisms including reflex blink, constant tear drainage, and rapid mucus turnover constitute great challenges for eye drops for effective drug delivery to the ocular epithelium. In this study, cyclosporine A (CsA) for the treatment of dry eye disease (DED) was selected as the model drug. Two strategies, PEGylation for mucus penetration and cationization for potent cellular uptake, were combined to construct a novel CsA nanosuspension (NS@lipid-PEG/CKC) by coating nanoscale drug particles with a mixture of lipids, DSPE-PEG2000, and a cationic surfactant, cetalkonium chloride (CKC). NS@lipid-PEG/CKC with the mean size ∼173 nm and positive zeta potential ∼+40 mV showed promoted mucus penetration, good cytocompatibility, more cellular uptake, and prolonged precorneal retention without obvious ocular irritation. More importantly, NS@lipid-PEG/CKC recovered tear production and goblet cell density more efficiently than the commercial cationic nanoemulsion on a dry eye disease rat model. All results indicated that a combination of PEGylation and cationization might provide a promising strategy to coordinate mucus penetration and cellular uptake for enhanced drug delivery to the ocular epithelium for nanomedicine-based eye drops.

Advancements in Nanosystems for Ocular Drug Delivery: A Focus on Pediatric Retinoblastoma.

The eye's complex anatomical structures present formidable barriers to effective drug delivery across a range of ocular diseases, from anterior to posterior segment pathologies. Emerging as a promising solution to these challenges, nanotechnology-based platforms-including but not limited to liposomes, dendrimers, and micelles-have shown the potential to revolutionize ophthalmic therapeutics. These nanocarriers enhance drug bioavailability, increase residence time in targeted ocular tissues, and offer precise, localized delivery, minimizing systemic side effects. Focusing on pediatric ophthalmology, particularly on retinoblastoma, this review delves into the recent advancements in functionalized nanosystems for drug delivery. Covering the literature from 2017 to 2023, it comprehensively examines these nanocarriers' potential impact on transforming the treatment landscape for retinoblastoma. The review highlights the critical role of these platforms in overcoming the unique pediatric eye barriers, thus enhancing treatment efficacy. It underscores the necessity for ongoing research to realize the full clinical potential of these innovative drug delivery systems in pediatric ophthalmology.

Comprehensive dry eye therapy: overcoming ocular surface barrier and combating inflammation, oxidation, and mitochondrial damage

BackgroundDry Eye Disease (DED) is a prevalent multifactorial ocular disease characterized by a vicious cycle of inflammation, oxidative stress, and mitochondrial dysfunction on the ocular surface, all of which lead to DED deterioration and impair the patients’ quality of life and social functioning. Currently, anti-inflammatory drugs have shown promising efficacy in treating DED; however, such drugs are associated with side effects. The bioavailability of ocular drugs is less than 5% owing to factors such as rapid tear turnover and the presence of the corneal barrier. This calls for investigations to overcome these challenges associated with ocular drug administration.ResultsA novel hierarchical action liposome nanosystem (PHP-DPS@INS) was developed in this study. In terms of delivery, PHP-DPS@INS nanoparticles (NPs) overcame the ocular surface transport barrier by adopting the strategy of “ocular surface electrostatic adhesion-lysosomal site-directed escape”. In terms of therapy, PHP-DPS@INS achieved mitochondrial targeting and antioxidant effects through SS-31 peptide, and exerted an anti-inflammatory effect by loading insulin to reduce mitochondrial inflammatory metabolites. Ultimately, the synergistic action of “anti-inflammation-antioxidation-mitochondrial function restoration” breaks the vicious cycle associated with DED. The PHP-DPS@INS demonstrated remarkable cellular uptake, lysosomal escape, and mitochondrial targeting in vitro. Targeted metabolomics analysis revealed that PHP-DPS@INS effectively normalized the elevated level of mitochondrial proinflammatory metabolite fumarate in an in vitro hypertonic model of DED, thereby reducing the levels of key inflammatory factors (IL-1β, IL-6, and TNF-α). Additionally, PHP-DPS@INS strongly inhibited reactive oxygen species (ROS) production and facilitated mitochondrial structural repair. In vivo, the PHP-DPS@INS treatment significantly enhanced the adhesion duration and corneal permeability of the ocular surface in DED mice, thereby improving insulin bioavailability. It also restored tear secretion, suppressed ocular surface damage, and reduced inflammation in DED mice. Moreover, it demonstrated favorable safety profiles both in vitro and in vivo.ConclusionIn summary, this study successfully developed a comprehensive DED management nanosystem that overcame the ocular surface transmission barrier and disrupted the vicious cycle that lead to dry eye pathogenesis. Additionally, it pioneered the regulation of mitochondrial metabolites as an anti-inflammatory treatment for ocular conditions, presenting a safe, efficient, and innovative therapeutic strategy for DED and other inflammatory diseases.

A mechanical device for precise self-administration of ocular drugs

Individuals with glaucoma are routinely prescribed and required to self-administer eye drop-based medication multiple times a day. Unfortunately, the process of self-administering eye drops requires a level of dexterity, strength, and visual acuity that the elderly population often do not possess, resulting in poor adherence and worsening condition. In this paper, we detail a prototyped eye drop assist device designed to safely and reliably deliver prescription medications. The ergonomic device safely anchors the eye drop bottle tip an optimal distance away from the face, aligns to the pupil, and provides feedback to the user when their head is at an appropriate tilt for a successful eye drop administration. We experimentally verify that the device improves hand steadiness, provides accurate head tilt feedback, precisely positions the bottle tip, and predictably delivers eye drops into the eye according to a parameterized model.

Microemulsion as Novel Drug Delivery for Fungal Eye Infection

The cornea, orbit, and other ocular tissues may get infected by fungi. Ophthalmic mycoses, often known as ocular fungal infections, are a significant cause of morbidity and blindness. For fungus infections, a brand-new azole derivative has been authorized. New immunological techniques would also be beneficial in the future for enhancing patient outcomes. Treatment of ocular illnesses presents a significant barrier in terms of getting medications into the eyes using traditional drug delivery methods, such as solutions. The main barriers are those between blood and the eyes, between lachrymal fluid and the eyes, and between medication losses from the ocular surface brought on by lachrymal fluid secretion. To increase the bioavailability and lengthen the residence duration of medications administered topically to the eye, a variety of ocular drug delivery carriers have been developed. The microemulsion is created using the PHASE TITRATION METHOD. Due to the dual hydrophilic and lipophilic properties of microemulsions, the loaded medications can diffuse passively and become significantly partitioned in the varying lipophilic-hydrophilic ocular barrier. This abstract will provide details on the microemulsions used to treat fungal infections of the eyes.

Optimization of stereolithography 3D printing of microneedle micro-molds for ocular drug delivery

Microneedles (MN) have emerged as an innovative technology for drug delivery, offering a minimally invasive approach to administer therapeutic agents. Recent applications have included ocular drug delivery, requiring the manufacture of sub-millimeter needle arrays in a reproducible and reliable manner. The development of 3D printing technologies has facilitated the fabrication of MN via mold production, although there is a paucity of information available regarding how the printing parameters may influence crucial issues such as sharpness and penetration efficacy. In this study, we have developed and optimized a 3D-printed MN micro-mold using stereolithography (SLA) 3D printing to prepare a dissolving ocular MN patch. The effects of a range of parameters including aspect ratio, layer thickness, length, mold shape and printing orientation have been examined with regard to both architecture and printing accuracy of the MN micro-mold, while the effects of printing angle on needle fidelity was also examined for a range of basic shapes (conical, pyramidal and triangular pyramidal). Mechanical strength and in vitro penetration of the polymeric (PVP/PVA) MN patch produced from reverse molds fabricated using MN with a range of shapes and height, and aspect ratios were assessed, followed by ex vivo studies of penetration into excised scleral and corneal tissues. The optimization process identified the parameters required to produce MN with the sharpest tips and highest dimensional fidelity, while the ex vivo studies indicated that these optimized systems would penetrate the ocular tissue with minimal applied pressure, thereby allowing ease of patient self-administration.

Development of a biodegradable polymer-based implant to release dual drugs for post-operative management of cataract surgery.

Cataract surgery is followed by post-operative eye drops for a duration of 4-6 weeks. The multitude of ocular barriers, coupled with the discomfort experienced by both the patient and their relatives in frequently administering eye drops, significantly undermines patient compliance, ultimately impeding the recovery of the patient. This study aimed to design and develop an ocular drug delivery system as an effort to achieve a drop-free post-operative care after cataract surgery. An implant was prepared containing a biodegradable polymer Poly-lactic-co-glycolic acid (PLGA), Dexamethasone (DEX) as an anti-inflammatory drug, and Moxifloxacin(MOX) as an antibiotic. Implant characterization and drug loading analysis were conducted. In vitro drug release profile showed that the release of the two drugs are correlated with the clinical prescription for post operative eye drops. In vivo study was conducted on New Zealand albino rabbits where one eye underwent cataract surgery, and the drug delivery implant was inserted into the capsular bag after placement of the synthetic intraocular lens (IOL). Borderline increase in the intraocular pressure (IOP) was noted in the test sample group. Slit-lamp observations revealed no significant anterior chamber reaction in all study groups. Histopathology study of the operated eye revealed no significant pathology in the test samples. This work aims at developing the intra ocular drug delivery implant which will replace the post-operative eye drops and help the patient with the post-operative hassle of eye drops.

Antioxidant Carbon Dots Nanozyme Loaded in Thermosensitive in situ Hydrogel System for Efficient Dry Eye Disease Treatment.

Dry eye disease (DED) is a multifactorial ocular surface disease with a rising incidence. Therefore, it is urgent to construct a reliable and efficient drug delivery system for DED treatment. In this work, we loaded C-dots nanozyme into a thermosensitive in situ gel to create C-dots@Gel, presenting a promising composite ocular drug delivery system to manage DED. This composite ocular drug delivery system (C-dots@Gel) demonstrated the ability to enhance adherence to the corneal surface and extend the ocular surface retention time, thereby enhancing bioavailability. Furthermore, no discernible ocular surface irritation or systemic toxicity was observed. In the DED mouse model induced by benzalkonium chloride (BAC), it was verified that C-dots@Gel effectively mitigated DED by stabilizing the tear film, prolonging tear secretion, repairing corneal surface damage, and augmenting the population of conjunctival goblet cells. Compared to conventional dosage forms (C-dots), the C-dots@Gel could prolong exhibited enhanced retention time on the ocular surface and increased bioavailability, resulting in a satisfactory therapeutic outcome for DED.

Recent Advancement of In-situ Gel for the treatment of Ocular disorder

The ocular drug delivery system is very crucial and difficult because the eye is the most sensitive part of the body. The in-situ drug delivery system is the smart way to deliver the drug in an ocular disorder with fewer risk factors. The in-situ drug delivery system promises to give fewer side effects and more effective effects. In the in-situ drug delivery system most of the drugs are formed from natural polymers. The formation of in situ gel is done in a way that they are solid at room temp and gel after it is administered in the eye. The in-situ drug delivery system is the safest system to deliver drugs for ocular disorders. There are many recent advancements in in situ drug delivery systems that are used to treat ocular disorders. innovative polymers and nanotechnologies offer tailored drug delivery effectively improving biocompatibility and biodegradation and reducing systemic side effects. By offering sustained drug release these devices solve problems with traditional drug delivery systems. The review highlights the in-situ gel drug delivery system for the treatment of the ocular disorder.

Ocular Drug Delivery into the Eyes Using Drug-Releasing Soft Contact Lens

The impact of visual impairment, such as blindness, on quality of life is immeasurable. However, effective ocular drug delivery into the eyes has not yet been established, primarily due to the impermeability imposed by the blood–retinal barrier (BRB) based on the tight junctions and efflux transporters at the endothelium or the epithelium in oral or intravenous administration, as well as the dilution with tear fluid and excretion through the nasolacrimal duct in eye drop administration. Furthermore, intravitreous injections induce pain and fear in patients. Unmet medical needs persist in ocular diseases such as age-related macular degeneration and diabetic retinopathy. Therefore, innovative non-invasive administration methods should be developed. Drug-releasing soft contact lenses (DR-SCLs) affixed to the eye’s surface can continuously and locally deliver their loaded drugs to the eyes. The use of DR-SCLs is expected to greatly enhance the bioavailability and patient adherence to the drug regimen. It is known that several solute carrier (SLC) transporters are expressed in various parts of the eyes, including the cornea, the ciliary body, and the bulbar conjunctiva. Carrier-mediated transport through SLC transporters may occur in addition to passive diffusion. Moreover, nanoparticles can be loaded into DR-SCLs, offering various intelligent approaches based on modifications to induce receptor-mediated endocytosis/transcytosis or to control the loaded drug release within this delivery system. In this perspective review, I discuss the implementation and potential of DR-SCL-mediated ocular drug delivery, particularly focusing on low-molecular-weight compounds because of their fine distribution in living body, ease of handling, and ease of manufacturing.

DESIGN AND OPTIMIZATION OF OCULAR INSERTS FOR PROLONGED DELIVERY OF CIPROFLOXACIN WITH CORTICOSTEROID

Ocular drug delivery is very challenging and fascinating for pharmaceutical researchers, especially in the treatment of ocular conjunctivitis. The challenges include delivery of the drug to the eye without causing permanent tissue damage while maintaining a stable therapeutic level at the site of action for a prolonged period of time. The present work focuses on the treatment of ocular conjunctivitis by using combined mechanisms of fluroquinolone antibiotics, providing sustained release of drug from ocular inserts, and using corticosteroid for anti-inflammatory effect and providing comfort to the patient. Quinolone antibiotics, anti-inflammatory agents and polymers with excipients were procured from pharmaceutical companies as gift samples. Different combinations of antibiotics and anti-inflammatory agents were prepared by solvent cast method and the dried films were cut into defined size containing drug and evaluated for different parameters and sustained drug release. Based on in vitro, in vivo correlation stability studies, the formulation (antibiotic + anti-inflammatory agent) promising the best once a day sustained release of the drug has been chosen.

A review on polymers in ocular drug delivery systems

AbstractAmid the escalating prevalence of eye diseases and the intricate nature of the eye as a crucial target organ for drug delivery, researchers face significant challenges in developing delivery systems tailored specifically for ocular complications. Addressing the gaps in the current conventional ocular drug delivery system (ODDS) is crucial and this can be achieved by incorporating polymers while designing newer ODDS. This review aims to offer a concise overview of the diverse polymers utilized in the development of ODDS, designed to address various eye conditions and disorders, enhance treatment outcomes, and ensure patient adherence. Introducing the anatomy of the eye and different ocular routes of administration, alongside the barriers encountered, this review presents polymer‐based ODDS, renowned for their unique properties facilitating the engineering of specialized devices for enhanced drug delivery. Further discussions delve into the applications of polymers in ophthalmology. Emphasis is placed on emerging polymer‐based technologies available in the market for treating ocular diseases, underscoring their potential for revolutionizing ocular healthcare. The review also addresses challenges in translating these advancements into clinical practice, while highlighting the versatility of polymers in treating diverse eye diseases and disorders through customizable properties and sustained drug delivery.

Liposomal drug delivery for glaucoma: Recent advancement in ocular therapy

Glaucoma affects millions worldwide. Untreated, it might cause lifelong blindness. Traditional treatments have been limited and intrusive. Liposomes are changing glaucoma treatment. Phospholipid bilayer liposomes can carry medications for targeted administration. This innovative glaucoma medication has huge potential to transform the way we treat it. This essay will explain liposomes, how they function, and why they are a glaucoma therapy game-changer. Eyes have several sensory compartments. Eyes send brain impulses. Eye-aqueous humour production causes glaucoma. It mostly affects the over-50s. Glaucoma destroys retinal ganglion cells and the optic nerve, causing blindness. CO2 inhibitors treat it. This inhibitor keeps aqueous humour from the ocular fluid. Normal eye medication dosage. This ocular drug administration approach relies on nasolacrimal drainage and tears turnover to provide the usual dose form. Low bioavailability. Novel pharmaceutical delivery dose formulations can fix this. Nano co-adhesive compositions prolong ocular drug delivery. Liposomes cure glaucoma uniquely. Bioavailability lowers toxicity and dosage. Novel Drug Delivery System helps glaucoma patients worldwide. Liposomes drop IOP slowly. Aqueous liposomes have natural and synthetic phospholipid bilayers. Liposomes contain hydrophilic medicines. Liposomes resemble cells. Their properties make them cling to cells. Biocompatible liposomes increase drug solubility, stability, absorption, and toxicity. Conjunctiva and cornea interactions with liposomes impact tear dynamics and medication duration and frequency. Novel eye medication delivery methods are being investigated. This medicine administration at the proper place challenges drug delivery systems. Here are innovative ocular drug-delivery methods. Biocompatible liposomes improve drug solubility, stability, absorption, and toxicity. Liposomes affect tear dynamics and medication duration and frequency via interacting with the conjunctiva and cornea. Novel ocular medicine delivery techniques for various eye ailments are being explored. This medication administration at the right place challenges drug delivery systems. Innovative ocular drug-delivery systems will be reviewed here.

Vesicular Drug Delivery Systems: Promising Approaches in Ocular Drug Delivery.

Ocular drug delivery poses unique challenges due to the complex anatomical and physiological barriers of the eye. Conventional dosage forms often fail to achieve optimal therapeutic outcomes due to poor bioavailability, short retention time, and off-target effects. In recent years, vesicular drug delivery systems have emerged as promising solutions to address these challenges. Vesicular systems, such as liposome, niosome, ethosome, transfersome, and others (bilosome, transethosome, cubosome, proniosome, chitosome, terpesome, phytosome, discome, and spanlastics), offer several advantages for ocular drug delivery. These include improved drug bioavailability, prolonged retention time on the ocular surface, reduced systemic side effects, and protection of drugs from enzymatic degradation and dilution by tears. Moreover, vesicular formulations can be engineered for targeted delivery to specific ocular tissues or cells, enhancing therapeutic efficacy while minimizing off-target effects. They also enable the encapsulation of a wide range of drug molecules, including hydrophilic, hydrophobic, and macromolecular drugs, and the possibility of combination therapy by facilitating the co-delivery of multiple drugs. This review examines vesicular drug delivery systems, their advantages over conventional drug delivery systems, production techniques, and their applications in management of ocular diseases.

Mucoadhesive electrospun nanofibrous poly(ε-caprolactone)/poly(lactic acid) matrices for the ocular delivery of moxifloxacin: a novel application of hyaluronic acid and xanthan gum blend as mucoadhesive coating agent

The use of ocular inserts (OS) as vehicles for the delivery of antimicrobial agents to the eye is rapidly growing. In fact, the intraOS can deliver the antibiotics to the ocular surface after ophthalmic surgeries i.e., cataract. This was a rational progress of pharmaceutical field given that the conventional dosage forms i.e., drops present many limitations. Considering this fact, in this study novel nanofibrous inserts based on poly(ε-caprolactone) and poly(lactic acid) prepared via electrospinning process and used to load an antibiotic drug, moxifloxacin. The used aliphatic polyesters are biocompatible but do not present mucoadhesion which is essential for ocular drug delivery. Therefore, two known mucoadhesive agents, hyaluronic acid and xanthan gum, were blended in various concentrations (0.1 and 0.2%) and used for the coating of the fibers. The fibrous inserts have mean diameters in the range 500–1000 nm. The inserts showed stability over time, improved water uptake and improved mechanical properties. In vitro cytotoxicity studies revealed the biocompatibility of the structures. From in vitro release studies, a controlled release rate was depicted while the inserts demonstrated desirable antimicrobial properties. It can be concluded that the coated OS can be potent ocular delivery carriers of moxifloxacin battling against eye infections.

A Review on Ocular Drug Delivery System

The major challenge faced by today’s pharmacologist and formulation scientist is ocular drug delivery. Topical eye drop is the most convenient and patient compliant route of drug administration, especially for the treatment of anterior segment diseases. Delivery of drugs to the targeted ocular tissues is restricted by various precorneal, dynamic and static ocular barriers. Also, therapeutic drug levels are not maintained for longer duration in target tissues. In the past two decades, ocular drug delivery research acceleratedly advanced towards developing a novel, safe and patient compliant formulation and drug delivery devices/techniques, which may surpass these barriers and maintain drug levels in tissues. Anterior segment drug delivery advances are witnessed by modulation of conventional topical solutions with permeation and viscosity enhancers. Also, it includes development of conventional topical formulations such as suspensions, emulsions and ointments. KEYWORDS: Cornea; Emulsions; Implants; Liposome; Nanomicelles;

Formulation and In Vitro-Ex vivo Evaluation of Cannabidiol and Cannabidiol-Valine-Hemisuccinate Loaded Lipid-Based Nanoformulations for Ocular Applications

The goal of this investigation is to develop stable ophthalmic nanoformulations containing cannabidiol (CBD) and its analog cannabidiol-valine-hemisuccinate (CBD-VHS) for improved ocular delivery. Two nanoformulations, nanoemulsion (NE) and nanomicelles (NMC), were developed and evaluated for physicochemical characteristics, drug-excipient compatibility, sterilization, thermal analysis, surface morphology, ex-vivo transcorneal permeation, corneal deposition, and stability.The saturation solubility studies revealed that among the surfactants tested, Cremophor EL had the highest solubilizing capacity for CBD (23.3 ± 0.1 mg/mL) and CBD-VHS (11.2 ± 0.2 mg/mL). The globule size for the lead CBD formulations (NE and NMC) ranged between 205 and 270 nm while CBD-VHS-NMC formulation had a particle size of about 78 nm. The sterilized formulations, except for CBD-VHS-NMC at 40 °C, were stable for three months of storage (last time point tested). Release, in terms of CBD, in the in-vitro release/diffusion studies over 18 h, were faster from the CBD-VHS nanomicelles (38 %) compared to that from the CBD nanoemulsion (16 %) and nanomicelles (33 %). Transcorneal permeation studies revealed improvement in CBD permeability and flux with both formulations; however, a greater improvement was observed with the NMC formulation compared to the NE formulation. In conclusion, the nanoformulations prepared could serve as efficient topical ocular drug delivery platforms for CBD and its analog.

Polymers and their engineered analogues for ocular drug delivery: Enhancing therapeutic precision.

Ocular drug delivery is constrained by anatomical and physiological barriers, necessitating innovative solutions for effective therapy. Natural polymers like hyaluronic acid, chitosan, and gelatin, alongside synthetic counterparts such as PLGA and PEG, have gained prominence for their biocompatibility and controlled release profiles. Recent strides in polymer conjugation strategies have enabled targeted delivery through ligand integration, facilitating tissue specificity and cellular uptake. This versatility accommodates combined drug delivery, addressing diverse anterior (e.g., glaucoma, dry eye) and posterior segment (e.g., macular degeneration, diabetic retinopathy) afflictions. The review encompasses an in-depth exploration of each natural and synthetic polymer, detailing their individual advantages and disadvantages for ocular drug delivery. By transcending ocular barriers and refining therapeutic precision, these innovations promise to reshape the management of anterior and posterior segment eye diseases.