Nanoparticulate ophthalmic drug delivery of norfloxacin to prevent ocular infection after cataract surgery: Evaluation in animal model

2021 ◽  
Vol 11 (8) ◽  
pp. 1402-1411
Author(s):  
Rong Wu ◽  
Qinying Huang ◽  
Zixia Zhou ◽  
Yile Chen ◽  
Huili Hu ◽  
...  

Post cataract surgery, patients generally experience bacterial infection called endophthalmitis which is considered as potent blinding complication. This infection arises from the colonization of Staphylococcus epidermidis on the newly implanted lense. To overcome this problem, we developed nanoparticulate ophthalmic drug delivery of Norfloxacin to prevent ocular infection after cataract surgery. Sustained release Norfloxacin loaded polymeric nanoparticles were developed by high pressure homogenization method. The nanoparticles were characterized for particle size, zeta potential, polydispersity index (PDI), encapsulation efficiency (EE), in vitro Norfloxacin release and surface characteristics using scanning electron microscopy (SEM). The optimized nanoparticulate formulation was further used for the development of thermoreversible ophthalmic gel using poloxamer polymer. The formulated ophthalmic gel was evaluated for gelation temperature, pH, bioadhesiveness, and in vitro corneal permeation study. The antibacterial efficacy testing of thermoreversible gel was assessed in animal model (rabbit) infected with Staphylococcus epidermidis. At the end of study period the inhibitory effect of thermoreversible gel was determined on test animals. The antibacterial effects were compared with control group and plain thermoreversible gel (without nanoparticle formulation). The optimized nanoparticulate formulation of Norfloxacin showed slow and gradual sustained release over the period of 72 hours, encapsulation efficiency of between 90.12 to 98.50%, particle size 95–210 nm, PDI 0.18 to 0.212 and zeta potential between 20 to 25 mV. The nanoparticles were found spherical and smooth in nature. The optimized formulation of nanoparticle was used in thermoreversible gel. The results obtained showed that the thermoreversible gel was clear and transparent (prime requirement for ophthalmic product) with high gelling capacity and moderately viscous liquid (1170 cp), highest bioadhesive strength of 2312.90 dyne/cm2. The exvivo corneal study showed excellent permeation through cornea as compare to control sample. Norfloxacin released from thermoreversible gel killed Staphylococcus epidermidis in animal models as compare to control group and showed effect up to 14 days. With these findings, we demonstrate a new and effective system for sustained drug release of Norfloxacin from thermoreversible gel with specific application to prevent ocular infection after cataract surgery.

2020 ◽  
Vol 26 (14) ◽  
pp. 1543-1555 ◽  
Author(s):  
Meltem E. Durgun ◽  
Emine Kahraman ◽  
Sevgi Güngör ◽  
Yıldız Özsoy

Background: Topical therapy is preferred for the management of ocular fungal infections due to its superiorities which include overcoming potential systemic side effects risk of drugs, and targeting of drugs to the site of disease. However, the optimization of effective ocular formulations has always been a major challenge due to restrictions of ocular barriers and physiological conditions. Posaconazole, an antifungal and highly lipophilic agent with broad-spectrum, has been used topically as off-label in the treatment of ocular fungal infections due to its highly lipophilic character. Micellar carriers have the potential to improve the solubility of lipophilic drugs and, overcome ocular barriers. Objective: In the current study, it was aimed optimization of posaconazole loaded micellar formulations to improve aqueous solubility of posaconazole and to characterize the formulations and to investigate the physical stability of these formulations at room temperature (25°C, 60% RH), and accelerated stability (40°C, 75% RH) conditions. Method: Micelles were prepared using a thin-film hydration method. Pre-formulation studies were firstly performed to optimize polymer/surfactant type and to determine their concentration in the formulations. Then, particle size, size distribution, and zeta potential of the micellar formulations were measured by ZetaSizer Nano-ZS. The drug encapsulation efficiency of the micelles was quantified by HPLC. The morphology of the micelles was depicted by AFM. The stability of optimized micelles was evaluated in terms of particle size, size distribution, zeta potential, drug amount and pH for 180 days. In vitro release studies were performed using Franz diffusion cells. Results: Pre-formulation studies indicated that single D-ɑ-tocopheryl polyethylene glycol succinate (TPGS), a combination of it and Pluronic F127/Pluronic F68 are capable of formation of posaconazole loaded micelles at specific concentrations. Optimized micelles with high encapsulation efficiency were less than 20 nm, approximately neutral, stable, and in aspherical shape. Additionally, in vitro release data showed that the release of posaconazole from the micelles was higher than that of suspension. Conclusion: The results revealed that the optimized micellar formulation of posaconazole offers a potential approach for topical ocular administration.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A750-A750
Author(s):  
Sojin Lee ◽  
Joon Young Park ◽  
Goo-Young Kim ◽  
Sang Woo Jo ◽  
Minhyuk Yun ◽  
...  

BackgroundSuccessful clinical translation of mRNA therapeutics requires an appropriate delivery strategy to overcome instability of mRNA and facilitate cellular uptake into the cells.1 Several lipid based nanoparticle approaches that encapsulate mRNA, notably lipid nanoparticle (LNP), have been developed, but their efficiency for delivery to certain target tissues and toxicity profiles still have room for improvement. The application of a novel polymer based nanoparticle technology platform, so called Stability Enhanced Nano Shells (SENS) for mRNA (mSENS) as a mRNA delivery platform for a cancer vaccine was demonstrated.MethodsThe physicochemical properties of mSENS formulation, particle size and encapsulation efficiency, were characterized using dynamic light scattering (DLS) and gel retardation assay. Using luciferase-encoding mRNA, the protein expression levels in vitro and in vivo were evaluated by luciferase assay or bioluminescence imaging (BLI), respectively. For cancer vaccine studies, antigen (tyrosinase-related protein 2 (Trp-2))-specific T cell responses were assessed by immunophenotyping mouse splenocytes using flow cytometry and by the enzyme-linked immunosorbent spot (ELISPOT) assay. The anti-tumor efficacy was studied in B16F10 lung tumor model in C57BL/6 mice. Liver and systemic toxicity of mSENS treated mice was evaluated through blood chemistry and complete blood count (CBC) tests.ResultsA library of mSENS formulations complexed with luciferase-encoding mRNA, were characterized for their particle size, surface charge, encapsulation efficiency, colloidal stability, and in vitro and in vivo luciferase protein expression level. Upon systemic administration in mice, varying biodistribution profiles were observed, implicating the potential for tailored delivery to target tissues. Particularly, cancer vaccine application was further developed leveraging the formulation with preferential spleen delivery. Following vaccination with Trp-2 mRNA encapsulated with mSENS (Trp-2 mRNA-mSENS) in B16F10 tumor bearing mice, strong Trp-2 antigen-specific IFN-γ T-cell responses were observed. Generated anti-tumor immunity also marked suppression of B16F10 lung tumors were observed in Trp-2-mSENS immunized mice compared to non-immunized controls, demonstrating the potential of mSENS as a mRNA delivery platform for the application for vaccine.ConclusionsProprietary biodegradable polymer based-mSENS platform offers an attractive delivery strategy for mRNA by tailoring to specific therapeutic applications. Depending on the application, whether it’s a vaccine or protein replacement, a rationally designed mSENS formulation can efficiently distribute mRNA to specific tissues. In particular, application of a splenic mSENS formulation for a cancer vaccine has been demonstrated in murine tumor model. In summary, mRNA delivery through mSENS platform is expected to provide significant opportunities in clinical development for mRNA therapeutics.Ethics ApprovalThe study was approved by Samyang Biopharmaceuticals’ IACUC (Institutional Animal Care and Use Committee), approval number SYAU-2027.ReferencePiotr S. Kowalski, Arnab Rudra, Lei Miao, and Daniel G. Anderson, delivering the messenger: advances in technologies for therapeutic mRNA delivery. Molecular Therapy Vol. 27 No 4 April 2019.


Author(s):  
Sumit Kumar ◽  
Dinesh Chandra Bhatt

Fabrication and evaluation of the Isoniazid loaded sodium alginate nanoparticles (NPs) was main objective of current investigation. These NPs were engineered using ionotropic gelation technique. The NPs fabricated, were evaluated for average particle size, encapsulation efficiency, drug loading, and FTIR spectroscopy along with in vitro drug release. The particle size, drug loading and encapsulation efficiency of fabricated nanoparticles were ranging from 230.7 to 532.1 nm, 5.88% to 11.37% and 30.29% to 59.70% respectively. Amongst all batches studied formulation F-8 showed the best sustained release of drug at the end of 24 hours.


Author(s):  
Chitra Gupta ◽  
VIJAY JUYAL ◽  
Upendra Nagaich

Objective: The present study emphasizes the synthesis, optimization, and evaluation of ocular in-situ gel for ophthalmic drug delivery against conjunctivitis. Methods: Pre-formulation studies on the drug and polymers were carried out, which included the study of various physicochemical properties of the drug and drug-polymer compatibility studies. The 12 different formulations were further pre-optimised by Taguchi method for determining the number of influential factors. Furthermore, the formulation optimization was done by using ‘Box–Behnken’ design (BBD) (Design expert 10 software) for assessing the effect of formulation variables on product characteristics viz. viscosity, gelation temperature (GT), and mean release time (MRT). About 13 suggested runs of the experiment were carried out and formulations were optimised. Finally, three batches of the optimised formulation were prepared and evaluated for in vitro drug release, isotonicity of formulation, anti-microbial potential, ocular irritancy, and accelerated stability testing. Results: Pre-formulation study confirmed the purity, solubility, and compatibility of drug measured by λmax, partition coefficient, stability study, and Fourier-transform infrared spectroscopy (FTIR) analysis. Taguchi screening method suggested about 12 different formulations and 3 most prominent influential factors including viscosity, GT, and drug release. 13 different formulations designed based on ‘BBD’ method were further optimised by considering the most influential factors suggested by Taguchi screening. The in vitro evaluation of the optimised formulation gave satisfactory results in terms of drug release, and anti-microbial activity. It was found to be isotonic with no ocular irritancy. Further, the preparation immediately transformed from sol to gel upon administration into cul-de-sac region of the eye due to multi-dimensional approaches utilised for in-situ gel formation namely temperature change Pluronic, ion sensitivity due to Gellan-gum, pH sensitivity because of Carbopol. Conclusion: The optimised in-situ gelling ocular drug formulation showed promising potency for ophthalmic drug delivery with no irritancy due to the multifactorial mechanism.


2002 ◽  
Vol 46 (9) ◽  
pp. 2885-2888 ◽  
Author(s):  
Andrea Giacometti ◽  
Oscar Cirioni ◽  
Roberto Ghiselli ◽  
Fiorenza Orlando ◽  
Federico Mocchegiani ◽  
...  

ABSTRACT A rat model was used to investigate the efficacy of quinupristin-dalfopristin (Q-D) in the prevention of vascular prosthetic graft infection due to methicillin-resistant Staphylococcus epidermidis with intermediate resistance to glycopeptides. The in vitro activity of the compound was compared to that of vancomycin by MIC determination and time-kill study. Moreover, the efficacy of collagen-sealed Q-D-soaked Dacron was evaluated in a rat model of graft infection. Graft infections were established in the subcutaneous tissue of the backs of 120 adult male Wistar rats. The in vivo study included a control group, one contaminated group that did not receive any antibiotic prophylaxis, two contaminated groups that received grafts soaked with 10 and 100 μg of Q-D per ml, respectively, and two contaminated groups that received grafts soaked with 10 and 100 μg of vancomycin per ml, respectively. Rats that received Dacron grafts soaked with 100 μg of Q-D per ml showed no evidence of infection (<10 CFU/ml). In contrast, for rats that received Dacron grafts soaked with 10 μg of Q-D per ml and Dacron grafts soaked with 10 or 100 μg of vancomycin per ml, the quantitative graft cultures demonstrated 2.2 × 102 ± 1.3 × 102, 2.2 × 106 ± 1.9 × 105, and 5.6 × 102 ± 0.3 × 102 CFU/ml, respectively. Taken together the results of the study demonstrate that the use of Dacron grafts soaked with Q-D can result in significant bacterial growth inhibition and show that this compound is potentially valuable for prevention of vascular prosthetic graft infection.


2012 ◽  
Vol 48 (1) ◽  
pp. 51-59 ◽  
Author(s):  
Cristiane da Silva Melo ◽  
Bruno Gonçalves Pereira ◽  
Armando Silva-Cunha ◽  
Sílvia Ligório Fialho

Interferon-alpha (IFN-alpha) is one of the main drugs used in the treatment of hepatitis C. Use of IFN-alpha has some limitations that result in poor treatment efficacy and low patient compliance. Therefore, the aim of this study was to develop poly-ε-caprolactone (PCL) microspheres containing IFN-alpha as an alternative for the treatment of chronic hepatitis C. Microspheres were prepared using the multiple emulsion followed by solvent evaporation technique. Particle size, surface morphology, drug content and encapsulation efficiency of the microspheres produced were evaluated. The stability of the formulation was assessed after 90 days at -20ºC. An in vitro release study was performed in PBS. In vitro cytotoxicity of the formulation was studied using hepatic cell line. The freeze-dried microspheres had mean particle size, IFN-alpha content, and encapsulation efficiency of 38.52 ± 4.64 µm, 15.52 ± 3.28% and 83.93 ± 5.76%, respectively. There were no significant changes during storage and the structural integrity of the protein was not compromised by the preparation technique. A total of 82% of the IFN-alpha was released after 28 days and the developed microspheres did not present cytotoxicity to the hepatic cell line. In vivo studies are currently underway to evaluate the biological activity of IFN-alpha encapsulated into microspheres.


Author(s):  
Salome A. Chime ◽  
Ikechukwu V. Onyishi ◽  
Ifeoma O. Eze

Objective: To formulate extended release gentamicin-entrapped lipospheres using natural lipids from Irvingia wombolu (IWF) and Moringa oleifera seed (MO) popularly known as Ben oil. Methods: Different lipid combinations including IWF and Phospholipon 90H (P90H) and IWF and MO were employed in the formulation of lipospheres. The formulations were analysed for particle size, encapsulation efficiency (EE), pH stability and antimicrobial studies amongst other tests. Also the in vitro release properties were studied in Phosphate buffer pH 7.2. Results: High EE of up to 90 % were obtained for the various LM combinations. The pH was stable over 30 days and the formulations showed about 93 % release of gentamicin at 12 h. Lipospheres formulated with MO matrices showed synergism in the microbial inhibition than other formulations. Conclusion: Natural lipids from Irvingia wombolu and Moringa oleifera seed could be used in formulating oral extended release gentamicin lipospheres.


2019 ◽  
Vol 9 (3) ◽  
pp. 212-221 ◽  
Author(s):  
Aparna Bhalerao ◽  
Pankaj Prakash Chaudhari

Cilinidipine is a fourth generation N and L-type calcium channel antagonists used alone or in combination with another drug to treat hypertension. Cilnidipine is poorly water -soluble, BCS class II drug with 6 to 30 percent oral bioavailability due to first pass metabolism. So to protect the drug from degradation and improve its dissolution, solid lipid nanoparticles were prepared. Glyceryl monostearate was selected as lipid while span 20: tween 20 were selected as surfactant blends. The formulations were evaluated for various parameters, as percent transmittance, drug content, percent encapsulation efficiency; percent drug loading, In vitro drug release and particle size. Optimized formulation was lyophilized using lactose as a cryo-protectant. The lyophilized formulation was evaluated for micromeritic properties, particle size and in vitro dissolution. It was further evaluated for DSC, XRD, and SEM. Percent encapsulation efficiency and percent drug loading of optimized formulation (F3) were 78.66percent and 9.44percent respectively. The particle size of F3 formulation without drug was 204 nm and with the drug was 214 nm. The particle size of the reconstituted SLN was 219 nm. In DSC study, no obvious peaks for cilnidipine were found in the SLN of cilnidipine indicated that the cilnidipine must be present in a molecularly dissolved state in SLN. In X-ray diffractometry absence of peaks representing crystals of cilnidipine in SLN indicated that the drug was in an amorphous or disordered crystalline phase in the lipid matrix. Thus, solid lipid nanoparticle formulation is a promising way to enhance the dissolution rate of cilnidipine. Keywords: Cilnidipine, Solid Lipid Nanoparticle, Hypertension


2019 ◽  
Vol 9 (4-A) ◽  
pp. 425-437
Author(s):  
Khushboo Verma ◽  
Jhakeshwar Prasad ◽  
Suman Saha ◽  
Surabhi Sahu

The aim of this work was to develop and evaluate curcumin loaded liposome and its bio- enhancement. Curcumin was selected as a natural drug for liposome formulation. Curcumin show variety of biological activity but it also shows poor bioavailability due to low aqueous solubility (1 µg/ml), poor absorption and rapid metabolism so that piperine was selected as bio enhancer to improve curcumin bioavailability. Soy lecithin and cholesterol were used to prepared curcumin and curcumin-piperine loaded liposome at different ratio by thin film hydration method because of easy to perform, and high encapsulation rates of lipid. The all liposome formulations (F1-F5) were evaluated by mean particle size, polydispersity index, zeta potential, encapsulation efficiency and drug release. Bioavailability was also determined on rat. Blood samples were collected at specific intervals, and plasma was separated by ultracentrifugation. Plasma was analyzed by high-performance liquid chromatography at 425 nm taking acetonitrile: water (75:25 v/v) acidified with 2% acetic acid as a mobile phase at a flow rate of 0.5 ml/min using C18 column. The mean particle size was found in the range between 800-1100 that indicate liposome are large unilamellar vesical types. By zeta potential study its conform that the all formulation was stable. The encapsulation efficiency of all liposome formulation are varied between 59-67%. In vitro drug release was analyse in 7.4 pH phosphate buffer, the maximum %CDR observed at the 12 hrs., and formulation are follow sustained release thus they reduce metabolism, good absorption rate which improve bioavailability of drug. From in-vivo study, it is clear that curcumin-piperine liposomal formulation, increases Cmax, area under the curve, and mean residence time significantly as compared to pure curcumin and pure curcumin liposome. Keywords: liposome; Curcumin; Piperine, Thin film hydration method; Bioavailability


Sign in / Sign up

Export Citation Format

Share Document