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1.
Biochem Biophys Res Commun ; 723: 150212, 2024 Sep 03.
Article En | MEDLINE | ID: mdl-38850812

Due to the presence of protective mechanisms and blood-ocular barriers in the eye, drugs aimed at treating posterior segment ophthalmic disorder have to be administrated mostly through periocular or intravitreal injection. In the current study, we sought to investigate whether topical ophthalmic instillation of human mesenchymal stem cells (hMSCs)-derived exosomes can prevent and treat experimental autoimmune uveitis (EAU), a posterior segment ophthalmic disease induced in animals and considered a model of human autoimmune diseases of the eye. Our studies reveal that topical ophthalmic instillation of hMSCs-derived exosomes can effectively ameliorate EAU. More importantly, we demonstrate that exosomes modified by trans-activator of transcription peptide (TAT) were more effective than naive exosomes in penetrating ocular barrier and preventing/treating EAU. Taken together, these results indicate that topical ophthalmic instillation of TAT-peptide modified exosomes represents a novel non-invasive therapeutic strategy for posterior-segment ophthalmic disorders.


Exosomes , Mesenchymal Stem Cells , Uveitis , Exosomes/metabolism , Exosomes/transplantation , Mesenchymal Stem Cells/metabolism , Mesenchymal Stem Cells/cytology , Humans , Animals , Uveitis/therapy , Uveitis/metabolism , Uveitis/pathology , Administration, Ophthalmic , Mice , Autoimmune Diseases/therapy , Autoimmune Diseases/metabolism , Autoimmune Diseases/immunology , Mice, Inbred C57BL , Administration, Topical , Posterior Eye Segment/metabolism , Female
3.
J Control Release ; 371: 43-66, 2024 Jul.
Article En | MEDLINE | ID: mdl-38735395

Microneedles (MNs) are micron-sized needles, typically <2 mm in length, arranged either as an array or as single needle. These MNs offer a minimally invasive approach to ocular drug delivery due to their micron size (reducing tissue damage compared to that of hypodermic needles) and overcoming significant barriers in drug administration. While various types of MNs have been extensively researched, significant progress has been made in the use of hollow MNs (HMNs) for ocular drug delivery, specifically through suprachoroidal injections. The suprachoroidal space, situated between the sclera and choroid, has been targeted using optical coherence tomography-guided injections of HMNs for the treatment of uveitis. Unlike other MNs, HMNs can deliver larger volumes of formulations to the eye. This review primarily focuses on the use of HMNs in ocular drug delivery and explores their ocular anatomy and the distribution of formulations following potential HMN administration routes. Additionally, this review focuses on the influence of formulation characteristics (e.g., solution viscosity, particle size), HMN properties (e.g., bore or lumen diameter, MN length), and routes of administration (e.g., periocular transscleral, suprachoroidal, intravitreal) on the ocular distribution of drugs. Overall, this paper highlights the distinctive properties of HMNs, which make them a promising technology for improving drug delivery efficiency, precision, and patient outcomes in the treatment of ocular diseases.


Administration, Ophthalmic , Drug Delivery Systems , Eye , Needles , Humans , Animals , Eye/metabolism , Pharmaceutical Preparations/administration & dosage , Microinjections/methods , Microinjections/instrumentation
4.
J Control Release ; 371: 67-84, 2024 Jul.
Article En | MEDLINE | ID: mdl-38768662

In situ gelling systems represent a burgeoning paradigm in ocular drug administration, addressing intrinsic challenges posed by extant ocular formulations, such as compromised bioavailability and constraints in traversing the corneal barrier. This systematic review endeavours to comprehensively examine the contemporary landscape of research in this domain, focusing on the nuanced capabilities of in situ gelling systems to optimize drug delivery and enhance therapeutic outcomes, without much technological complexity. Employing a meticulous search strategy across diverse databases for publications and patents spanning the years 2015 to 2023 a total of 26 research papers and 14 patents meeting stringent inclusion criteria were identified. Synthesizing the collective insights derived from these investigations, it becomes evident that in situ gelling systems confer an ability to protract the residence time of formulations or active pharmaceutical ingredients (APIs) within the ocular milieu. This sustained presence engenders extended drug release kinetics, thereby fostering improved patient compliance and mitigating the proclivity for side effects attendant to frequent dosing. These salutary effects extend to diminished systemic drug absorption, augmented ocular bioavailability, and the prospect of reduced dosing frequencies, thereby amplifying patient adherence to therapeutic regimens. Intriguingly, the protective attributes of in situ gelling systems extend to the establishment of an ocular surface barrier, thereby abating the susceptibility to infections and inflammatory responses. In summation, this review underscores the auspicious potential of in situ gelling systems as a transformative approach to advancing ocular drug delivery, warranting sustained research endeavours and developmental initiatives for the betterment of global patient outcomes.


Administration, Ophthalmic , Drug Delivery Systems , Gels , Humans , Animals , Biological Availability , Eye/metabolism , Pharmaceutical Preparations/administration & dosage , Pharmaceutical Preparations/chemistry , Ophthalmic Solutions/administration & dosage
5.
AAPS PharmSciTech ; 25(5): 119, 2024 May 30.
Article En | MEDLINE | ID: mdl-38816667

Loteprednol etabonate (LE) is a topical corticosteroid for the symptomatic management of ocular conditions, encompassing both allergic and infectious etiologies. Owing to the dynamic and static barriers of the eye, LE exhibits significantly low bioavailability, necessitating an increase in the frequency of drug administration. The objective of this study is to overcome the limitations by developing niosomal systems loaded with LE. Design of Experiments (DoE) approach was used for the development of optimal niosome formulation. The optimal formulation was characterized using DLS, FT-IR, and DSC analysis. In vitro and ex vivo release studies were performed to demonstrate drug release patterns. After that HET-CAM evaluation was conducted to determine safety profile. Then, in vivo studies were carried out to determine therapeutic activity of niosomes. Zeta potential (ZP), particle size, polydispersity index (PI), and encapsulation efficacy (EE) were -33.8 mV, 89.22 nm, 0.192, and 89.6%, respectively. Medicated niosomes had a broad distribution within rabbit eye tissues and was absorbed by the aqueous humor of the bovine eye for up to 6 h after treatment. Cumulative permeated drug in the bovine eye and rabbit eye were recorded 52.45% and 54.8%, respectively. No irritation or hemorrhagic situation was observed according to the results of HET-CAM study. Thus, novel LE-loaded niosomal formulations could be considered as a promising treatment option for the dry-eye-disease (DED) due to enhanced bioavailability and decreased side effects.


Delayed-Action Preparations , Dry Eye Syndromes , Liposomes , Loteprednol Etabonate , Animals , Rabbits , Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/pharmacokinetics , Loteprednol Etabonate/administration & dosage , Loteprednol Etabonate/pharmacokinetics , Dry Eye Syndromes/drug therapy , Cattle , Drug Liberation , Particle Size , Disease Models, Animal , Administration, Ophthalmic , Biological Availability , Drug Delivery Systems/methods , Eye/metabolism , Eye/drug effects , Aqueous Humor/metabolism , Chemistry, Pharmaceutical/methods , Ophthalmic Solutions/administration & dosage , Ophthalmic Solutions/pharmacokinetics
6.
Int J Pharm ; 658: 124184, 2024 Jun 10.
Article En | MEDLINE | ID: mdl-38692497

The present study systematically investigates the impact of active pharmaceutical ingredient (API) variables and oleaginous base characteristics on the in vitro release (IVR) performance of ophthalmic ointments, utilizing dexamethasone as a model drug. The interplay between selected attributes (i.e., particle size distribution, crystallinity, and polymorphic form for API, and rheological factors for compendial-grade white petrolatum) and IVR performance was investigated. APIs from different vendors exhibited variations in crystallinity and polymorphism. Ointments containing amorphous dexamethasone presented higher release amounts/rates compared to crystalline counterparts, emphasizing the role of physical state in release kinetics. Variations in particle size of this lipophilic API (5.4 - 21.2 µm) did not appear to impact IVR performance significantly. In contrast, white petrolatum's rheological attributes, which varied substantially within USP-grade petrolatum, were found to critically affect the drug release rate and extent of the ointment. The study's comprehensive analysis establishes a coherent connection between the quality attributes of both API and petrolatum and IVR, delineating their intricate interdependent effects on ophthalmic ointment performance. These findings provide reference to formulation design, quality control, and regulatory considerations within the pharmaceutical industry, fostering a robust foundational understanding of commonly overlooked quality attributes in ophthalmic ointments.


Administration, Ophthalmic , Dexamethasone , Drug Liberation , Ointments , Particle Size , Petrolatum , Rheology , Dexamethasone/chemistry , Dexamethasone/administration & dosage , Petrolatum/chemistry , Crystallization , Chemistry, Pharmaceutical/methods
7.
Int J Pharm ; 658: 124192, 2024 Jun 10.
Article En | MEDLINE | ID: mdl-38703931

Ocular delivery is the most challenging aspect in the field of pharmaceutical research. The major hurdle for the controlled delivery of drugs to the eye includes the physiological static barriers such as the complex layers of the cornea, sclera and retina which restrict the drug from permeating into the anterior and posterior segments of the eye. Recent years have witnessed inventions in the field of conventional and nanocarrier drug delivery which have shown considerable enhancement in delivering small to large molecules across the eye. The dynamic challenges associated with conventional systems include limited drug contact time and inadequate ocular bioavailability resulting from solution drainage, tear turnover, and dilution or lacrimation. To this end, various bioactive-based nanosized carriers including liposomes, ethosomes, niosomes, dendrimer, nanogel, nanofibers, contact lenses, nanoprobes, selenium nanobells, nanosponge, polymeric micelles, silver nanoparticles, and gold nanoparticles among others have been developed to circumvent the limitations associated with the conventional dosage forms. These nanocarriers have been shown to achieve enhanced drug permeation or retention and prolong drug release in the ocular tissue due to their better tissue adherence. The surface charge and the size of nanocarriers (10-1000 nm) are the important key factors to overcome ocular barriers. Various nanocarriers have been shown to deliver active therapeutic molecules including timolol maleate, ampicillin, natamycin, voriconazole, cyclosporine A, dexamethasone, moxifloxacin, and fluconazole among others for the treatment of anterior and posterior eye diseases. Taken together, in a nutshell, this extensive review provides a comprehensive perspective on the numerous facets of ocular drug delivery with a special focus on bioactive nanocarrier-based approaches, including the difficulties and constraints involved in the fabrication of nanocarriers. This also provides the detailed invention, applications, biodistribution and safety-toxicity of nanocarriers-based therapeutcis for the ophthalmic delivery.


Administration, Ophthalmic , Drug Carriers , Drug Delivery Systems , Eye , Nanoparticles , Humans , Animals , Drug Carriers/chemistry , Eye/metabolism , Eye/drug effects , Drug Delivery Systems/methods , Nanoparticles/chemistry , Eye Diseases/drug therapy , Nanoparticle Drug Delivery System/chemistry , Biological Availability , Drug Liberation
8.
Int J Pharm ; 658: 124195, 2024 Jun 10.
Article En | MEDLINE | ID: mdl-38703935

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.


Administration, Ophthalmic , Drug Delivery Systems , Needles , Printing, Three-Dimensional , Stereolithography , Animals , Microinjections/methods , Microinjections/instrumentation , Cornea/metabolism , Sclera , Swine , Technology, Pharmaceutical/methods
9.
Molecules ; 29(10)2024 May 11.
Article En | MEDLINE | ID: mdl-38792122

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.


Drug Delivery Systems , Retinoblastoma , Retinoblastoma/drug therapy , Humans , Drug Carriers/chemistry , Child , Nanoparticles/chemistry , Micelles , Liposomes/chemistry , Dendrimers/chemistry , Retinal Neoplasms/drug therapy , Administration, Ophthalmic , Nanotechnology/methods
10.
Biol Pharm Bull ; 47(5): 1033-1042, 2024.
Article En | MEDLINE | ID: mdl-38797668

Eye drops, including solutions and suspensions, are essential dosage forms to treat ophthalmic diseases, with poorly water-soluble drugs typically formulated as ophthalmic suspensions. In addition to low bioavailability, suspensions exhibit limited efficacy, safety, and usability due to the presence of drug particles. Improving bioavailability can reduce the drug concentrations and the risk of problems associated with suspended drug particles. However, practical penetration enhancers capable of improving bioavailability remain elusive. Herein, we focused on penetratin (PNT), a cell-penetrating peptide (CPP) that promotes active cellular transport related to macromolecule uptake, such as micropinocytosis. According to the in vitro corneal uptake study using a reconstructed human corneal epithelial tissue model, LabCyte CORNEA-MODEL24, PNT enhanced the uptake of Fluoresbrite® YG carboxylate polystyrene microspheres without covalent binding. In an ex vivo porcine eye model, the addition of 10 µM PNT to rebamipide ophthalmic suspension markedly improved the corneal uptake of rebamipide; however, the addition of 100 µM PNT was ineffective due to potentially increased particle size by aggregation. This article provides basic information on the application of PNT as a penetration enhancer in ophthalmic suspensions, including the in vitro and ex vivo studies mentioned above, as well as the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay and storage stability at different pH values.


Cell-Penetrating Peptides , Cornea , Ophthalmic Solutions , Suspensions , Animals , Cell-Penetrating Peptides/chemistry , Cell-Penetrating Peptides/administration & dosage , Ophthalmic Solutions/administration & dosage , Humans , Cornea/metabolism , Cornea/drug effects , Swine , Quinolones/administration & dosage , Quinolones/pharmacokinetics , Quinolones/chemistry , Administration, Ophthalmic , Biological Availability , Epithelium, Corneal/drug effects , Epithelium, Corneal/metabolism , Particle Size , Alanine/analogs & derivatives
11.
Int J Biol Macromol ; 270(Pt 1): 132302, 2024 Jun.
Article En | MEDLINE | ID: mdl-38744357

Nanocrystalline cellulose (NCC) is a star material in drug delivery applications due to its good biocompatibility, large specific surface area, high tensile strength (TS), and high hydrophilicity. Poly(Vinyl Alcohol)/Gellan-gum-based innovative composite film has been prepared using nanocrystalline cellulose (PVA/GG/NCC) as a strengthening agent for ocular delivery of moxifloxacin (MOX) via solvent casting method. Impedance analysis was studied using the capacitive sensing technique for examining new capacitance nature of the nanocomposite MOX film. Antimicrobial properties of films were evaluated using Pseudomonas aeruginosa and Staphylococcus aureus as gram-negative and gram-positive bacteria respectively by disc diffusion technique. XRD revealed the characteristic peak of NCC and the amorphous form of the drug. Sustained in vitro release and enhanced corneal permeation of drug were noticed in the presence of NCC. Polymer matrix enhanced the mechanical properties (tensile strength 22.05 to 28.41 MPa) and impedance behavior (resistance 59.23 to 213.23 Ω) in the film due to the presence of NCC rather than its absence (16.78 MPa and 39.03 Ω respectively). Occurrence of NCC brought about good antimicrobial behavior (both gram-positive and gram-negative) of the film. NCC incorporated poly(vinyl alcohol)/gellan-gum-based composite film exhibited increased mechanical properties and impedance behavior for improved ocular delivery of moxifloxacin.


Cellulose , Moxifloxacin , Nanoparticles , Polysaccharides, Bacterial , Polyvinyl Alcohol , Moxifloxacin/chemistry , Moxifloxacin/pharmacology , Polyvinyl Alcohol/chemistry , Cellulose/chemistry , Polysaccharides, Bacterial/chemistry , Nanoparticles/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/administration & dosage , Staphylococcus aureus/drug effects , Drug Delivery Systems , Nanocomposites/chemistry , Drug Liberation , Drug Carriers/chemistry , Animals , Administration, Ophthalmic , Pseudomonas aeruginosa/drug effects , Tensile Strength , Microbial Sensitivity Tests
12.
Vestn Oftalmol ; 140(2): 102-111, 2024.
Article Ru | MEDLINE | ID: mdl-38742506

Dry eye disease (DED) is pathogenetically based on inflammation of the ocular surface. A step-by-step approach to DED treatment involves early initiation of anti-inflammatory therapy, including instillation of cyclosporine A (CsA). However, recommendations for the use of topical CsA in clinical practice are limited. This article presents an expert consensus on practical recommendations for the management of patients with DED, including indications, time of initiation and duration of CsA therapy, comparison of CsA forms currently registered in the Russian Federation, as well as issues of patient education.


Cyclosporine , Emulsions , Humans , Administration, Ophthalmic , Cyclosporine/administration & dosage , Dry Eye Syndromes/drug therapy , Dry Eye Syndromes/etiology , Immunosuppressive Agents/administration & dosage , Ophthalmic Solutions/administration & dosage , Treatment Outcome , Xerophthalmia/etiology , Xerophthalmia/drug therapy , Xerophthalmia/diagnosis
13.
Methods ; 228: 1-11, 2024 Aug.
Article En | MEDLINE | ID: mdl-38759909

The necessity of animal-free performance tests for novel ophthalmic formulation screening is challenging. For this, we developed and validated a new device to simulate the dynamics and physical-chemical barriers of the eye for in vitro performance tests of topic ophthalmic formulations. The OphthalMimic is a 3D-printed device with an artificial lacrimal flow, a cul-de-sac area, a support base, and a simulated cornea comprised of a polymeric membrane containing poly-vinyl alcohol 10 % (w/v), gelatin 2.5 % (w/v), and different proportions of mucin and poloxamer, i.e., 1:1 (M1), 1:2 (M2), and 2:1 (M3) w/v, respectively. The support base is designed to move between 0° and 50° to replicate the movement of an eyelid. We challenged the model by testing the residence performance of poloxamer®407 16 % and poloxamer®407 16 % + chitosan 1 % (PLX16CS10) gels containing fluconazole. The test was conducted with a simulated tear flow of 1.0 mL.min-1 for 5 min. The OphthalMimic successfully distinguished PLX16 and PLX16C10 formulations based on their fluconazole drainage (M1: 65 ± 14 % and 27 ± 10 %; M2: 58 ± 6 % and 38 ± 9 %; M3: 56 ± 5 % and 38 ± 18 %). In conclusion, the OphthalMimic is a promising tool for comparing the animal-free performance of ophthalmic formulations.


Ophthalmic Solutions , Poloxamer , Poloxamer/chemistry , Ophthalmic Solutions/chemistry , Administration, Ophthalmic , Fluconazole/administration & dosage , Printing, Three-Dimensional , Cornea/drug effects , Cornea/metabolism , Animals , Chitosan/chemistry , Animal Testing Alternatives/methods , Tears/chemistry , Humans , Gelatin/chemistry
14.
Int J Pharm ; 658: 124226, 2024 Jun 10.
Article En | MEDLINE | ID: mdl-38744414

This review article provides a comprehensive overview of the advancements in using nanosuspensions for controlled drug delivery in ophthalmology. It highlights the significance of ophthalmic drug delivery due to the prevalence of eye diseases and delves into various aspects of this field. The article explores molecular mechanisms, drugs used, and physiological factors affecting drug absorption. It also addresses challenges in treating both anterior and posterior eye segments and investigates the role of mucus in obstructing micro- and nanosuspensions. Nanosuspensions are presented as a promising approach to enhance drug solubility and absorption, covering formulation, stability, properties, and functionalization. The review discusses the pros and cons of using nanosuspensions for ocular drug delivery and covers their structure, preparation, characterization, and applications. Several graphical representations illustrate their role in treating various eye conditions. Specific drug categories like anti-inflammatory drugs, antihistamines, glucocorticoids, and more are discussed in detail, with relevant studies. The article also addresses current challenges and future directions, emphasizing the need for improved nanosuspension stability and exploring potential technologies. Nanosuspensions have shown substantial potential in advancing ophthalmic drug delivery by enhancing solubility and absorption. This article is a valuable resource for researchers, clinicians, and pharmaceutical professionals in this field, offering insights into recent developments, challenges, and future prospects in nanosuspension use for ocular drug delivery.


Administration, Ophthalmic , Drug Delivery Systems , Eye Diseases , Nanoparticles , Suspensions , Humans , Eye Diseases/drug therapy , Drug Delivery Systems/methods , Animals , Solubility , Ophthalmology/methods
15.
Int J Pharm ; 659: 124249, 2024 Jun 25.
Article En | MEDLINE | ID: mdl-38772496

This study aimed to develop, optimize, and evaluate hot-melt-extruded ophthalmic inserts capable of sustained release of diquafosol tetrasodium (DQS) via a design of experiments approach. DQS, a tear stimulant for dry eye management, faces challenges of frequent administration and low bioavailability. The developed insert uses biodegradable polymers in varied proportions to achieve sustained release. Optimized through mixture design, the insert completely dissolved within 24 h and maintained a stable drug content, thickness, and surface pH over three months at room temperature. In vitro corneal permeation studies on excised rabbit corneas demonstrated increased bioavailability, suggesting a reduced dosing frequency compared with conventional eye drops. Therefore, this insert has potential to enhance treatment outcomes by improving patient compliance and providing sustained drug effects.


Cornea , Delayed-Action Preparations , Polyphosphates , Uracil Nucleotides , Rabbits , Animals , Polyphosphates/chemistry , Uracil Nucleotides/administration & dosage , Uracil Nucleotides/chemistry , Cornea/metabolism , Cornea/drug effects , Ophthalmic Solutions/administration & dosage , Ophthalmic Solutions/chemistry , Biological Availability , Drug Liberation , Administration, Ophthalmic , Drug Compounding/methods , Drug Implants , Hot Temperature , Chemistry, Pharmaceutical/methods
16.
Int J Pharm ; 659: 124252, 2024 Jun 25.
Article En | MEDLINE | ID: mdl-38782149

Although rare, amoebic keratitis (AK) is a disease caused by Acanthamoeba spp. that can lead to blindness. The drugs currently available for its treatment are very toxic, which has motivated the investigation for more effective and safe therapeutic options. In this study, the in vitro activity of ß-caryophyllene (BCP) was exploited taking into account its action against other protozoans as well as its well-known healing and anti-inflammatory properties (aspects relevant for the AK pathogenesis). On the other hand, high volatilization and oxidation phenomena are found for this compound, which led to its incorporation into nanoemulsions (NEs). Two emulsifying agents were tested, resulting in monodisperse systems with reduced droplet size (<265 nm) and high surface charge (positive and negative for NEs prepared with cetrimonium bromide -CTAB and Phosal® 50+, respectively). NEs prepared with CTAB were shown to be more stable after long-term storage at 4 and 25 °C than those prepared with Phosal®. Pure BCP, at the highest concentration (500 µM), resulted in a level of inhibition of Acanthamoeba trophozoites equivalent to that of reference drug (chlorhexidine). This activity was even greater after oil nanoencapsulation. The reduced droplet size could improve the interaction of the oil with the microorganism, justifying this finding. Changes in surface charge did not impact the activity. Positively charged NEs improved the interaction and retention of BCP in the cornea and thus should be prioritized for further studies.


Acanthamoeba Keratitis , Emulsions , Polycyclic Sesquiterpenes , Acanthamoeba Keratitis/drug therapy , Acanthamoeba Keratitis/parasitology , Polycyclic Sesquiterpenes/chemistry , Nanoparticles , Administration, Ophthalmic , Cetrimonium/chemistry , Animals , Acanthamoeba/drug effects , Drug Stability , Particle Size , Ophthalmic Solutions , Humans
17.
Int J Pharm ; 659: 124265, 2024 Jun 25.
Article En | MEDLINE | ID: mdl-38795935

Metformin (MET) can be an alternative therapeutic strategy for managing ocular burn primarily because of its pleiotropic mechanism. Longer retention on the ocular surface and sustained release are necessary to ensure the efficacy of MET for ocular application. Although the high aqueous solubility of MET is good for formulation and biocompatibility, it makes MET prone to high nasolacrimal drainage. This limits ocular residence and may be a challenge in its application. To address this, polymers approved for ophthalmic application with natural origin were analyzed through in silico methods to determine their ability to bind to mucin and interact with MET. An ocular insert of MET (3 mg/6 mm) was developed using a scalable solvent casting method without using preservatives. The relative composition of the insert was 58 ± 2.06 %w/w MET with approximately 14 %w/w tamarind seed polysaccharide (TSP), and 28 %w/w propylene glycol (PG). Its stability was demonstrated as per the ICH Q1A (R2) guidelines. Compatibility, ocular retention, drug release, and other functional parameters were evaluated. In rabbits, efficacy was demonstrated in the 'corneal alkali burn preclinical model'. TSP showed potential for mucoadhesion and interaction with MET. With adequate stability and sterility, the insert contributed to adequate retention of MET (10-12 h) in vivo and slow release (30 h) in vitro. This resulted in significant efficacy in vivo.


Delayed-Action Preparations , Drug Liberation , Eye Burns , Metformin , Polysaccharides , Seeds , Tamarindus , Animals , Metformin/chemistry , Metformin/administration & dosage , Rabbits , Tamarindus/chemistry , Polysaccharides/chemistry , Seeds/chemistry , Eye Burns/drug therapy , Eye Burns/chemically induced , Administration, Ophthalmic , Drug Implants , Male , Burns, Chemical/drug therapy , Drug Stability , Corneal Injuries/drug therapy , Cornea/metabolism , Cornea/drug effects , Propylene Glycol/chemistry , Solubility
18.
Int J Pharm ; 659: 124279, 2024 Jun 25.
Article En | MEDLINE | ID: mdl-38806096

Controlled release drug delivery systems of eye drops are a promising ophthalmic therapy with advantages of good patient compliance and low irritation. However, the lack of a suitable drug carrier for ophthalmic use limits the development of the aforementioned system. Herein, the crosslinked cyclodextrin organic framework (COF) with a cubic porous structure and a uniform particle size was synthesized and applied to solidify vitamin A palmitate (VAP) by using the solvent-free method. The VAP@COF suspension eye drops were formulated by screening co-solvents, suspending agents, and stabilizing agents to achieve a homogeneous state and improve stability. According to the in vitro release study, the VAP@COF suspension exhibited a controlled release of VAP within 12 h. Both the ex vivo corneal contact angle and in vivo fluorescence tracking indicated that the VAP@COF suspension prolonged the VAP residence time on the ocular surface. This suspension accelerated the recovery of the dry eye disease (DED) model in New Zealand rabbits. Furthermore, the suspension was non-cytotoxic to human corneal epithelial cells and non-irritation to rabbit eyes. In summary, the particulate COF is an eye-acceptable novel carrier that sustains release and prolongs the VAP residence time on the ocular surface for DED treatment.


Delayed-Action Preparations , Drug Carriers , Drug Liberation , Dry Eye Syndromes , Retinyl Esters , Vitamin A , Animals , Rabbits , Vitamin A/administration & dosage , Vitamin A/chemistry , Vitamin A/analogs & derivatives , Dry Eye Syndromes/drug therapy , Humans , Drug Carriers/chemistry , Cyclodextrins/chemistry , Ophthalmic Solutions/administration & dosage , Particle Size , Male , Cell Line , Cross-Linking Reagents/chemistry , Administration, Ophthalmic , Disease Models, Animal , Drug Delivery Systems/methods , Diterpenes
19.
Int J Biol Macromol ; 270(Pt 2): 132522, 2024 Jun.
Article En | MEDLINE | ID: mdl-38768922

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.


Glucans , Moxifloxacin , Nanoparticles , Xylans , Xylans/chemistry , Glucans/chemistry , Moxifloxacin/chemistry , Moxifloxacin/pharmacokinetics , Moxifloxacin/pharmacology , Animals , Rabbits , Nanoparticles/chemistry , Drug Carriers/chemistry , Anti-Bacterial Agents/pharmacokinetics , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/administration & dosage , Sulfhydryl Compounds/chemistry , Cornea/metabolism , Cornea/drug effects , Humans , Drug Delivery Systems , Permeability , Cell Line , Administration, Ophthalmic , Adhesiveness , Adhesives/chemistry
20.
Int J Pharm ; 658: 124222, 2024 Jun 10.
Article En | MEDLINE | ID: mdl-38735632

Dry eye disease (DED) is a chronic multifactorial disorder of the ocular surface caused by tear film dysfunction and constitutes one of the most common ocular conditions worldwide. However, its treatment remains unsatisfactory. While artificial tears are commonly used to moisturize the ocular surface, they do not address the underlying causes of DED. Apigenin (APG) is a natural product with anti-inflammatory properties, but its low solubility and bioavailability limit its efficacy. Therefore, a novel formulation of APG loaded into biodegradable and biocompatible nanoparticles (APG-NLC) was developed to overcome the restricted APG stability, improve its therapeutic efficacy, and prolong its retention time on the ocular surface by extending its release. APG-NLC optimization, characterization, biopharmaceutical properties and therapeutic efficacy were evaluated. The optimized APG-NLC exhibited an average particle size below 200 nm, a positive surface charge, and an encapsulation efficiency over 99 %. APG-NLC exhibited sustained release of APG, and stability studies demonstrated that the formulation retained its integrity for over 25 months. In vitro and in vivo ocular tolerance studies indicated that APG-NLC did not cause any irritation, rendering them suitable for ocular topical administration. Furthermore, APG-NLC showed non-toxicity in an epithelial corneal cell line and exhibited fast cell internalization. Therapeutic benefits were demonstrated using an in vivo model of DED, where APG-NLC effectively reversed DED by reducing ocular surface cellular damage and increasing tear volume. Anti-inflammatory assays in vivo also showcased its potential to treat and prevent ocular inflammation, particularly relevant in DED patients. Hence, APG-NLC represent a promising system for the treatment and prevention of DED and its associated inflammation.


Apigenin , Drug Carriers , Dry Eye Syndromes , Lipids , Nanoparticles , Animals , Apigenin/administration & dosage , Apigenin/chemistry , Apigenin/pharmacology , Apigenin/pharmacokinetics , Drug Carriers/chemistry , Dry Eye Syndromes/drug therapy , Humans , Rabbits , Lipids/chemistry , Lipids/administration & dosage , Cell Line , Nanoparticles/chemistry , Administration, Ophthalmic , Drug Liberation , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/pharmacokinetics , Particle Size , Nanostructures/administration & dosage , Nanostructures/chemistry , Male
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