18 results on '"ophthalmic drug delivery"'
Search Results
2. Timolol-loaded ethosomes for ophthalmic delivery: Reduction of high intraocular pressure in vivo
- Author
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Uner, Burcu, Ozdemir, Samet, Nur Pilevne, Seniz, and Cenk Celebi, Ali Rıza
- Published
- 2023
- Full Text
- View/download PDF
3. In situ formation of injectable organogels for punctal occlusion and sustained release of therapeutics: design, preparation, in vitro and in vivo evaluation
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Cao, Ziqin, Chen, Yangnan, Bai, Shaoyun, Zheng, Zhiyun, Liu, Yan, Gui, Shuangying, Shan, Shuang, Wu, Jiabao, and He, Ning
- Published
- 2023
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4. Nanosuspensions in ophthalmology: Overcoming challenges and enhancing drug delivery for eye diseases.
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Fathi-Karkan, Sonia, Amiri Ramsheh, Nasim, Arkaban, Hasan, Narooie-Noori, Foroozan, Sargazi, Sara, Mirinejad, Shekoufeh, Roostaee, Maryam, Sargazi, Saman, Barani, Mahmood, Malahat Shadman, Seyedeh, Althomali, Raed H., and Rahman, Mohammed M.
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OPHTHALMIC drugs , *ANTERIOR eye segment , *POSTERIOR segment (Eye) , *DRUG solubility , *EYE diseases , *DRUG absorption - Abstract
[Display omitted] 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. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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5. Acetazolamide encapsulation in elastin like recombinamers using a supercritical antisolvent (SAS) process for glaucoma treatment.
- Author
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Vallejo, Reinaldo, Quinteros, Daniela, Gutiérrez, Javier, Martínez, Sofía, Rodríguez Rojo, Soraya, Ignacio Tártara, Luis, Palma, Santiago, and Javier Arias, Francisco
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ACETAZOLAMIDE , *ZETA potential , *GLAUCOMA , *ATOMIC force microscopy , *ELASTIN , *TRANSMISSION electron microscopy - Abstract
[Display omitted] • Encapsulation of acetazolamide in ELRs nanoparticles using SAS technique. • ELR-based nanoparticles system offering more permeation ocular of Acetazolamide. • Tests on hypertensive rabbits show high bioavailability and hypotensive effect. Glaucoma, the second most common cause of blindness worldwide, requires the development of new and effective treatments. This study introduces a novel controlled-release system utilizing elastin-like recombinamers (ELR) and the Supercritical Antisolvent (SAS) technique with supercritical CO2. Acetazolamide (AZM), a class IV drug with limited solubility and permeability, is successfully encapsulated in an amphiphilic ELR at three different ELR:AZM ratios, yielding up to 62 %. Scanning electron microscopy (SEM) reveals spherical microparticles that disintegrate into monodisperse nanoparticles measuring approximately 42 nm under physiological conditions. The nanoparticles, as observed via Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM), do not exhibit aggregates, a fact confirmed by the zeta potential displaying a value of –33 mV over a period of 30 days. Transcorneal permeation tests demonstrate a 10 % higher permeation level compared to the control solution, which increases to 30 % after 2 h. Ocular irritation tests demonstrate no adverse effects or damage. Intraocular pressure (IOP) tests conducted on hypertensive rabbits indicate greater effectiveness for all three analyzed formulations, suggesting enhanced drug bioavailability during treatment. Consequently, the combination of recombinant biopolymers and high-pressure techniques represents a promising approach for advancing glaucoma therapy, emphasizing its potential clinical significance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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6. Micelle-solubilized axitinib for ocular administration in anti-neovascularization.
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Shi, Shuai, Peng, Fangli, Zheng, Qianqian, Zeng, Li, Chen, Hao, Li, Xingyi, and Huang, Jinhai
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COPOLYMER micelles , *POLYCAPROLACTONE , *PROTEIN-tyrosine kinases - Abstract
Graphical abstract Axitinib was loaded into self-assembled micelles by for ocular surface treatment of corneal neovascularization. Abstract The development of new blood vessels is directly related to the occurrence of eye diseases. Anti-angiogenic drugs can theoretically be extended to the treatment of ophthalmic diseases. In this study, axitinib, a class of tyrosine kinase inhibitors, was loaded via the amphiphilic copolymer MPEG-PCL, improving its dispersibility in water. Axitinib-loaded micelles showed low toxicity in concentration gradient assays. Additionally, multiple doses by scratch assay confirmed that axitinib had no significant effect on normal cell migration, and biosafety test results showed good cell compatibility. After we established the corneal neovascularization model after an alkali burn in rats, the anti-angiogenic efficacy was tested, with dexamethasone as a positive control. The results showed that axitinib-loaded micelles had anti-angiogenic effects without obvious tissue toxicity. As a class of targeted tyrosine kinase inhibitors, axitinib can be used in the treatment of ocular neovascular diseases through nanocrystallization. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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7. Directing the nanoparticle formation by the combination with small molecular assembly and polymeric assembly for topical suppression of ocular inflammation.
- Author
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Huang, Jinhai, Yu, Xinxin, Zhou, Yanfang, Zhang, Renshu, Song, Qianqian, Wang, Qinmei, and Li, Xingyi
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NANOPARTICLE synthesis , *UVEITIS treatment , *DRUG design , *TRIAMCINOLONE acetonide , *HYDROGELS - Abstract
Graphical abstract Abstract In this paper, we presented a simple yet versatile strategy to generate a high drug payload nanoparticles by the combination with small molecular assembly and polymeric assembly for topical suppression of ocular inflammation. Upon physical mixing of the succinated triamcinolone acetonide (TA-SA) supramolecular hydrogel with the poly (ethylene glycol)-poly (ɛ-caprolactone)-poly (ethylene glycol) (PECE) aqueous solution at 37 °C, TA-SA/PECE nanoparticles formed spontaneously and characterized thoroughly by transmission electron microscopy (TEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The formed TA-SA/PECE nanoparticles displayed a comparable in vitro anti-inflammatory efficacy to that of native triamcinolone acetonide (TA), through a significant downregulation of various proinflammatory cytokines levels (e.g., NO, TNF-α) in a lipopolysaccharide (LPS) actived RAW264.7 macrophage. Meanwhile, the enhanced transcorneal drug permeability of TA-SA/PECE nanoparticles over that of TA suspension was clearly observed in an isolated rabbit cornea. Intraocular biocompatibility test demonstrated that TA-SA/PECE nanoparticles presented good biocompatibility after topical instillation during entire study period. More importantly, the TA-SA/PECE nanoparticles displayed superior therapeutic efficacy over that of the TA suspension in the endotoxin-induced uveitis (EIU) rabbit model via decreasing neutrophil infiltration in anterior chamber. Overall, the proposed TA-SA/PECE nanoparticles might be a promising candidate for uveitis therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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8. Preparation and evaluation of ascorbyl glucoside and ascorbic acid solid in oil nanodispersions for corneal epithelial wound healing.
- Author
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Jaber, Mai, Jaber, Bahaa, Hamed, Saja, and AlKhatib, Hatim S.
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CORNEA injuries , *VITAMIN C , *WOUND healing , *CASTOR oil , *EYE drops , *DRUG delivery systems , *PETROLEUM - Abstract
[Display omitted] • Ascorbic acid (AA)- and Ascorbyl glycoside (AA-2G)-loaded Solid in Oil (S/O) nanodispersions were developed. • AA-2G (S/O) nanodispersions improved transcorneal penetration and accumulation. • AA and AA-2G (S/O) nanodispersion based oily eye drops showed superior activity in promoting corneal epithelial wound healing in comparison to aqueous solutions of AA and AA-2G. • (S/O) nanodispersions show great potential as ocular drug delivery systems. The objective of this study was to develop and evaluate an effective topical formulation to promote corneal epithelial wound healing. Ascorbyl glucoside (AA-2G), a stable prodrug of AA, was formulated in solid in oil (S/O) nanodispersions by emulsifying AA-2G solutions in cyclohexane using Span 85 as an emulsifying agent and freeze-drying emulsions to produce AA-2G – surfactant complex. The complexes were then dispersed in castor oil to produce S/O nanodispersions which were evaluated in terms of their particle size, polydispersity index, encapsulation efficiency, morphology, physical stability as well as the transcorneal permeation and accumulation of AA-2G. The same preparation procedure was used to prepare S/O nanodispersions of AA. S/O nanodispersions of AA and AA-2G were formulated into oily drops that were tested for efficacy in promoting wound healing after corneal epithelial depredation. AA-2G was loaded efficiently in S/O nanodispersions (EE > 99%) in the form of spherical nanoparticles. S/O nanodispersions were physically stable and resulted in improved permeation (18x) and accumulation (7x) of AA-2G in transcorneal diffusion experiments in comparison to AA-2G solutions. Oily eye drops of AA-2G and AA showed no irritation and significant improvement in epithelial healing in vivo in comparison to AA-2G and AA solutions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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9. Drug loading optimization and extended drug delivery of corticoids from pHEMA based soft contact lenses hydrogels via chemical and microstructural modifications.
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García-Millán, Eva, Koprivnik, Sandra, and Otero-Espinar, Francisco Javier
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POLYHEMA , *SOFT contact lenses , *DRUG delivery systems , *ADRENOCORTICAL hormones , *HYDROGELS , *MICROSTRUCTURE - Abstract
This paper proposes an approach to improve drug loading capacity and release properties of poly(2-hydroxyethyl methacrylate) (p(HEMA)) soft contact lenses based on the optimization of the hydrogel composition and microstructural modifications using water during the polymerization process. P(HEMA) based soft contact lenses were prepared by thermal or photopolymerization of 2-hydroxyethyl methacrylate (HEMA) solutions containing ethylene glycol di-methacrylate as crosslinker and different proportions of N -vinyl-2-pyrrolidone (NVP) or methacrylic acid (MA) as co-monomers. Transmittance, water uptake, swelling, microstructure, drug absorption isotherms and in vitro release were characterized using triamcinolone acetonide (TA) as model drug. Best drug loading ratios were obtained with lenses containing the highest amount (200 mM) of MA. Incorporation of 40% V/V of water during the polymerization increases the hydrogel porosity giving a better drug loading capacity. In vitro TA release kinetics shows that MA hydrogels released the drug significantly faster than NVP-hydrogels. Drug release was found to be diffusion controlled and kinetics was shown to be reproducible after consecutive drug loading/release processes. Results of p(HEMA) based soft contact lenses copolymerized with ethylene glycol dimethacrylate (EGDMA) and different co-monomers could be a good alternative to optimize the loading and ocular drug delivery of this corticosteroid drug. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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10. High-throughput in vitro drug release and pharmacokinetic simulation as a tool for drug delivery system development: Application to intravitreal ocular administration.
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Sarkhel, Sanjay, Ramsay, Eva, Kontturi, Leena-Stiina, Peltoniemi, Jonne, and Urtti, Arto
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CONTROLLED release drugs , *SIMULATION methods & models , *DRUG delivery systems , *DRUG development , *OCULAR pharmacology , *DRUG administration , *PHARMACOKINETICS , *IN vitro studies - Abstract
In vitro estimation of release kinetics from drug delivery systems is needed in formulation development. Cost-effective methods of assessment for delivery systems are needed particularly in the case of biologicals and drug administration routes that are difficult to screen in vivo ( e . g . intraocular drug delivery). As a proof-of-concept, we demonstrate here a practical high-throughput methodology to investigate in vitro drug release and predict resulting drug concentrations in the eye after intravitreal administration. 96-well plate based assay aided with robotic sampling was used to study release of eight model drugs of varying physicochemical properties (dexamethasone, vancomycin, alpha-lactalbumin, lysozyme, myoglobin, albumin, lactoferrin, human IgG) from twelve alginate microsphere formulations. The amount of drug released over a period of time was assessed by photometric and fluorescence methods. In vitro drug release rates obtained were used in pharmacokinetic simulations using one-compartment model of the vitreal cavity with anatomical volume of distribution and clearance estimates based on the literature precedence. An integrated approach of drug release screening and pharmacokinetic simulations can prove to be a useful methodology in guiding formulation development for ocular delivery in animal models. In general, the methodology has the potential to be a cost-effective tool for early stage drug delivery system discovery and development. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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11. Optimization and evaluation of thermoresponsive diclofenac sodium ophthalmic in situ gels
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Asasutjarit, Rathapon, Thanasanchokpibull, Suthira, Fuongfuchat, Asira, and Veeranondha, Sukitaya
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DICLOFENAC , *PHARMACEUTICAL gels , *SODIUM compounds , *OPHTHALMOLOGY , *TRANSITION temperature , *HUMIDITY - Abstract
Abstract: This work was conducted to optimize and evaluate Pluronic F127-based thermoresponsive diclofenac sodium ophthalmic in situ gels (DS in situ gel). They were prepared by cold method and investigated their physicochemical properties i.e., pH, flow ability, sol–gel transition temperature, gelling capacity and rheological properties. An optimized formulation was selected and investigated its physicochemical properties before and after autoclaving, eye irritation potency in SIRC cells and rabbits. In vivo ophthalmic absorption was performed in rabbits. It was found that physicochemical properties of DS in situ gels were affected by formulation compositions. Increment of Pluronic F127 content decreased sol–gel transition temperature of the products while increase in Pluronic F68 concentration tended to increase sol–gel transition temperature. In this study, Carbopol 940 did not affect sol–gel transition temperature but it affected transparency, pH, and gelling capacity of the products. The optimized formulation exhibited sol–gel transition at 32.6±1.1°C with pseudoplastic flow behavior. It was lost diclofenac sodium content during autoclaving. However, it was accepted as safe for ophthalmic use and could increase diclofenac sodium bioavailability in aqueous humor significantly. In conclusion, the optimized DS in situ gel had potential for using as an alternative to the conventional diclofenac sodium eye drop. However, autoclaving was not a suitable sterilization method for this product. [Copyright &y& Elsevier]
- Published
- 2011
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12. Dispersion of microemulsion drops in HEMA hydrogel: a potential ophthalmic drug delivery vehicle
- Author
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Gulsen, Derya and Chauhan, Anuj
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EMULSIONS (Pharmacy) , *HYDROGELS , *DISPERSION (Chemistry) , *DRUG delivery devices - Abstract
Abstract: Approximately 90% of all ophthalmic drug formulations are now applied as eye-drops. While eye-drops are convenient and well accepted by patients, about 95% of the drug contained in the drops is lost due to absorption through the conjunctiva or through the tear drainage. A major fraction of the drug eventually enters the blood stream and may cause side effects. The drug loss and the side effects can be minimized by using disposable soft contact lenses for ophthalmic drug delivery. The essential idea is to encapsulate the ophthalmic drug formulations in nanoparticles, and disperse these drug-laden particles in the lens material. Upon insertion into the eye, the lens will slowly release the drug into the pre lens (the film between the air and the lens) and the post-lens (the film between the cornea and the lens) tear films, and thus provide drug delivery for extended periods of time. This paper focuses on dispersing stabilized microemulsion drops in poly-2-hydroxyethyl methacrylate (p-HEMA) hydrogels. The results of this study show that the p-HEMA gels loaded with a microemulsion that is stabilized with a silica shell are transparent and that these gels release drugs for a period of over 8 days. Contact lenses made of microemulsion-laden gels are expected to deliver drugs at therapeutic levels for a few days. The delivery rates can be tailored by controlling the particle and the drug loading. It may be possible to use this system for both therapeutic drug delivery to eyes and the provision of lubricants to alleviate eye problems prevalent in extended lens wear. [Copyright &y& Elsevier]
- Published
- 2005
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13. Release of ciprofloxacin from poloxamer-graft-hyaluronic acid hydrogels in vitro
- Author
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Cho, K.Y., Chung, T.W., Kim, B.C., Kim, M.K., Lee, J.H., Wee, W.R., and Cho, C.S.
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CIPROFLOXACIN , *TISSUE mechanics - Abstract
Recently, in situ gel formation has extensively been studied to enhance ocular bioavailability and duration of the drug activity. In this study, we report grafting of poloxamer onto the hyaluronic acid for application of tissue engineering oriented ophthalmic drug delivery system. Graft copolymers were prepared by coupling mono amine-terminated poloxamer (MATP) with hyaluronic acid (HA) backbone using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxylsuccinimide (NHS) as coupling agents. The coupling of MATP with HA was clarified by
1H NMR and FT-IR spectroscopy. The gelation temperature of graft copolymers was dependent on the content of HA and the concentration of poloxamer. From drug release studies in vitro, ciprofloxacin was sustainedly released from the poloxamer-g-hyaluronic acid hydrogel due to the in situ gel formation of the copolymer and viscous properties of HA. [Copyright &y& Elsevier]- Published
- 2003
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14. Safety assessment of polymeric micelles as an ophthalmic drug delivery system for intravitreal administration of dasatinib.
- Author
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Li, Qingqing, Qian, Xiaobing, Li, Ho Yin, Lai, Ka Lun, Gao, Qianying, and Lee, Wai Yip Thomas
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DRUG delivery systems , *OPHTHALMIC drugs , *OCULAR toxicology , *DASATINIB , *MICELLES , *OPTICAL coherence tomography - Abstract
• Dasatinib-loaded micelles showed remarkable safety profiles at cellular levels. • The micelles caused negligible ocular toxicity post-intravitreal injection. • The micelles did not insult the cornea, as proved by slit-lamp biomicroscopy. • The micelles did not insult the retina, as demonstrated by Histology & OCT study. • The micelles caused negligible apoptosis and stresses to the retina. Ocular safety/biocompatibility is an essential element of ophthalmic drug delivery. We previously applied poly(ethylene glycol)-block-poly(ɛ-caprolactone) (PEG-b-PCL) micelles to deliver dasatinib for the management of proliferative vitreoretinopathy (PVR) in vitro. Herein, we seek to ascertain the ocular safety/compatibility of blank and dasatinib loaded PEG-b-PCL micelles, which will set the stage for the future in vivo efficacy evaluations and/or clinical translation for PVR or other eye diseases. To access the safety of blank and dasatinib loaded micelles, in vitro cell based assays (LDH cell membrane damage test, SRB cytotoxicity, TEER and permeability of RPE tight junctions), in vivo slit lamp biomicroscopy and optical coherence tomography, Ex vivo histology (H&E staining, GFAP immunofluorescence staining and TUNEL assay) were undertaken. Both blank and dasatinib loaded micelles showed remarkable safety profiles at cellular levels. They also caused negligible ocular toxicity/abnormalities up to 28 days post-intravitreal injection in mice. The micelles did not insult the cornea, as demonstrated by slit-lamp biomicroscopy. Ex vivo histology and in vivo optical coherence tomography revealed a normal retinal structure with minimal apoptosis and stresses. Taken together, both blank and dasatinib loaded micelles appear to be safe and their applications in drug delivery for eye diseases should be explored. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
15. Formulation development and in vitro evaluation of transferrin-conjugated liposomes as a carrier of ganciclovir targeting the retina.
- Author
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Asasutjarit, Rathapon, Managit, Chittima, Phanaksri, Teva, Treesuppharat, Worapapar, and Fuongfuchat, Asira
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LIPOSOMES , *TRANSFERRIN , *RETINA , *RHODOPSIN , *BIOLOGICAL pigments , *TARGETED drug delivery , *DRUG delivery systems - Abstract
Transferrin-conjugated liposomes containing ganciclovir (GCV) significantly increased the concentration of GCV in the human retinal pigment epithelial cells, the ARPE-19 cells, after incubation for 24 h. • Formulation of transferrin-conjugated liposomes for delivery of ganciclovir to the retina. • Optimized ganciclovir-loaded liposomes for intravitreal injection and topical instillation. • Interactions between ingredients of the liposome studied by Fourier transform infrared analysis. • Mechanism of cellular uptake of ganciclovir-loaded liposomes by the retinal cells. Ganciclovir (GCV) is an antiviral drug approved for treatment of cytomegalovirus (CMV) retinitis. It can be delivered to the eye via systemic administrations. However, local delivery of GCV that targets the retina is considered as an alternative to increase efficacy of the treatment and lessen side effects. Thus, this study aimed to develop formulations of transferrin (Tf)-conjugated liposomes containing GCV (Tf-GCV-LPs) for intravitreal injection and topical instillation. Tf-GCV-LPs were prepared by the reverse-phase evaporation technique and then conjugated to Tf. Their physicochemical properties were evaluated. The optimized formulation was selected and subjected to the cytotoxicity test, cellular uptake study in the human retinal pigment epithelial cells (the ARPE-19 cells) and antiviral activity evaluation. The results showed that physicochemical properties of Tf-GCV-LPs were affected by formulation compositions. The optimized Tf-GCV-LPs had a particle size lower than 100 nm with a negative value of zeta potential. They were safe for the ARPE-19 cells. These Tf-GCV-LPs were taken up by these cells via Tf receptors-mediated endocytosis and showed inhibitory activity on CMV in the infected cells. Therefore, the optimized Tf-GCV-LPs could be accepted as a promising drug delivery system for targeted GCV delivery to the retina in the treatment of CMV retinitis. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
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16. Antimicrobial activity and biocompatibility of slow-release hyaluronic acid-antibiotic conjugated particles.
- Author
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Zhang, Ze, Suner, Selin S., Blake, Diane A., Ayyala, Ramesh S., and Sahiner, Nurettin
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OPHTHALMIC surgery , *PARTICLES , *DRUG carriers , *BIOCOMPATIBILITY , *INFECTION prevention , *DRUG coatings - Abstract
• Hyaluronic Acid (HA) microgel as long lasting antibiotic releasing system. • HA particles to prevent bacterial infections with no toxicity to corneal endothelium. • Ciprofloxacin and vancomycin conjugated HA particles for ophthalmologic applications. Here, the aim was to design and use a long-lasting antibiotic release system for prevention of postoperative infections in ophthalmic surgery. Ciprofloxacin and vancomycin-conjugated hyaluronic acid (HA) particles were prepared as drug carriers for sustained release of antibiotics. The antimicrobial effects of the released drugs were determined by disc-diffusion and macro-dilution tests at different times up to 2 weeks. Slow degradable HA particles were obtained with 35.2 wt% degradation within 21 days. The drug loading amount was increased by employing two sequential chemical linking (conjugation, 2C) and one physical absorption loading (A) procedures (2C + A processes) from 148 ± 8 to 355 ± 11 mg/g HA particles for vancomycin. The amounts of vancomycin and ciprofloxacin that were released linearly was estimated as 64.35 ± 7.35 and 25.00 ± 0.68 mg/g, respectively, from drug-conjugated HA particles in 100 h. Antimicrobial studies revealed that antibiotic-conjugated HA particles could inhibit the growth of microorganisms from 1 h to 1 week. The MBC values were measured as 0.25, 4.0, and 0.25 mg/mL against Pseudomonas aeruginosa , Staphylococcus aureus , and Bacillus subtilis , respectively, after 72 h incubation time. Cytotoxicity studies showed no difference between fibroblast growth or corneal thickness after 5 days with or without HA-antibiotic particles. The drug release studies and antimicrobial activity of antibiotic-loaded HA particles with time against various bacteria further revealed that HA particles are very effective in preventing bacterial infections. Likewise, cytotoxicity studies suggest that these particles pose no toxicity to eukaryotic cells, including corneal endothelium. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
17. Mucoadhesive dexamethasone-glycol chitosan nanoparticles for ophthalmic drug delivery.
- Author
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Yu, Ailing, Shi, Hui, Liu, Hui, Bao, Zhishu, Dai, Mali, Lin, Dan, Lin, Deqing, Xu, Xu, Li, Xingyi, and Wang, Yuqin
- Subjects
- *
OPHTHALMIC drugs , *DEXAMETHASONE , *CHITOSAN , *FOURIER transform infrared spectroscopy , *X-ray powder diffraction , *NANOPARTICLES , *TRANSMISSION electron microscopy - Abstract
Self-assembly of drug-polysacrrides conjugates forming nanostructures provides a simple and promising strategy for the extension of precorneal retention and enhancement of corneal permeability. In the present study, a series of dexamethasone-glycol chitosan (Dex-GCS) conjugates were synthesized and thoroughly characterized by Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD) and ultraviolet–visible (UV–Vis) spectroscopy. The resulting Dex-GCS conjugates were able to self-assemble into nanoparticles spontaneously with particle sizes in the range of 277–289 nm and a positive charge of approximately +15 mV. Roughly spherical nanoparticles were observed by transmission electron microscopy (TEM). The in vitro mucoadhesive properties of Dex-GCS nanoparticles were evaluated by recording the variations in the zeta potential after incubation with different concentrations of mucin. In vitro release studies performed in phosphate-buffered saline (PBS, pH = 7.4) indicated progressive Dex release up to 8 h, followed by a plateau up to 48 h. Dex-GCS nanoparticles caused slight cytotoxicity against L929, HCEC and RAW 264.7 cells after 24 h of incubation and displayed a nearly identical anti-inflammatory efficacy to dexamethasone sodium phosphate (Dexp) in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. More importantly, the proposed Dex-GCS nanoparticles showed good ocular tolerance and provided a relatively longer precorneal duration compared with that of the aqueous solution formulation, which suggested that the self-assembled Dex-GCS nanoparticle might be a promising candidate for ophthalmic drug delivery. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
18. Thermosensitive glycol chitosan-based hydrogel as a topical ocular drug delivery system for enhanced ocular bioavailability.
- Author
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Shi, Hui, Wang, Yuan, Bao, Zhishu, Lin, Deqing, Liu, Hui, Yu, Ailing, Lei, Lei, Li, Xingyi, and Xu, Xu
- Subjects
- *
DRUG delivery systems , *HYDROGELS , *ETHYLENE glycol , *BIOAVAILABILITY , *CHITOSAN , *AQUEOUS solutions , *SCANNING electron microscopy - Abstract
In the present study, we developed and evaluated an in situ gelling system based on hexanoyl glycol chitosan (H-GCS) for enhanced ocular bioavailability. An aqueous solution of H-GCS exhibited a typical sol-gel transition at 32 °C. The formed H-GCS hydrogel was characterized by rheology and scanning electron microscopy (SEM). H-GCS had minimal in vitro cytotoxicity against L-929 and HCEC cells over a concentration range of 0–0.8 mg/mL. Additionally, the H-GCS hydrogel exhibited good ocular tolerance and biocompatibility after a single instillation. Moreover, H-GCS hydrogel significantly prolonged the precorneal retention of fluorescein sodium compared with its aqueous solution. An in vivo pharmacokinetic study demonstrated that the levofloxacin-loaded H-GCS hydrogel could provide a significantly higher C max and AUC 0-12h compared with the levofloxacin aqueous solution, thus increasing ocular bioavailability. Overall, the proposed H-GCS hydrogel acts as an in situ gelling system that might represent a promising vehicle for topical ocular drug delivery. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
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