DEVELOPMENT AND CHARACTERIZATION OF NON-IONIC SURFACTANT VESICLES FOR OPHTHALMIC DRUG DELIVERY OF DICLOFENAC POTASSIUM

Non-ionic surfactant vesicles was developed and characterized for ophthalmic drug delivery of Diclofenac potassium. The present research study is a promising approach to improve corneal penetration and bioavailability characteristics. Formulation also found to ensure a good entrapment efficiency and ocular bioavailability of drug in-vivo. Non-ionic surfactant vesicles containing Diclofenac potassium were prepared using surfactant and cholesterol in different ratio by Lipid film hydration technique. Niosomes were characterized For Entrapment efficiency, Particle size analysis, In-vitro drug release and In-vivo studies. The best formulation selected based on above parameters were subjected for sustained release study. Formulation with low cholesterol content which shown 82.1% Entrapment efficiency, 70.01% sustained release over a period of 10 h followed a non-fickian profile with zero order release profile. Scanning electron micrograph indicated that Niosomes have a discrete spherical structure without aggregation. In-vivo study showed an availability of drug in aqueous humor for an extended time period even up to 8 hour and it showed a correlation with the release profile in-vitro. Non-ionic surfactant vesicles are considered the best as it showed good and high Entrapment efficiency and Vitro release with better bioavailability. The proposed method was found to be precise and selective for the development and characterization of Diclofenac potassium Niosomes. Key words: Diclofenac potassium, corneal penetration, sorbitan mono stearate, Entrapment efficiency, SEM, in vitro release study, HPLC

DEVELOPMENT AND EVALUATION OF MUCOADHESIVE MICROSPHERES OF LEVOFLOXACIN HYDROCHLORIDE

Levofloxacin microspheres with  mucoadhesive polymers like Sodium Alginate, Sodium Carboxymethyl Cellulose and Carbopol-940 were prepared by w/o emulsification solvent evaporation method and evaluated. The resulting microspheres were small, discrete, spherical and free flowing. The microspheres showed significant mucoadhesive property in the in-vitro wash-off test. The drug release from the mucoadhesive microspheres followed the controlled release profile. and first order kinetics. Drug release was controlled by the diffusion mechanism. Stability studies were performed at three different temperatures for six weeks. All the formulation showed satisfactory stability profile

Comparative accuracy of CT, dual-echo MRI and MR spectroscopy for preoperative liver fat quantification in living related liver donors

Background: It is of significant importance to assess the extent of hepatic steatosis in living donor liver transplant (LDLT) surgery to ensure optimum graft regeneration as well as donor safety. Aim: To establish the accuracy of non-invasive imaging methods including computed tomography (CT), dual-echo in- and opposed-phase magnetic resonance imaging (MRI), and MR spectroscopy (MRS) for quantification of liver fat content (FC) in prospective LDLT donors with histopathology as reference standard. Settings and Design: This retrospective study was conducted at our institution on LDLT donors being assessed for biliary and vascular anatomy depiction by Magnetic Resonance Cholangiopancreatography (MRCP) and CT scan, respectively, between July 2013 and October 2014. Materials and Methods: Liver FC was measured in 73 donors by dual-echoT1 MRI and MRS. Of these, CT liver attenuation index (LAI) values were available in 62 patients. Statistical Analysis: CT and MRI FC were correlated with histopathological reference standard using Spearman correlation coefficient. Sensitivity, specificity, positive predictive value, negative predicative value, and positive and negative likelihood ratios with 95% confidence intervals were obtained. Results: CT LAI, dual-echo MRI, and MRS correlated well with the histopathology results (r = 0.713, 0.871, and 0.882, respectively). An accuracy of 95% and 96% was obtained for dual-echo MRI and MRS in FC estimation with their sensitivity being 97% and 94%, respectively. False-positive rate, positive predictive value (PPV), and negative predicative value (NPV) were 0.08, 0.92, and 0.97, respectively, for dual-echo MRI and 0.03, 0.97, and 0.95, respectively, for MRS. CT LAI method of fat estimation has a sensitivity, specificity, PPV, and NPV of 73%, 77.7%, 70.4%, and 80%, respectively. Conclusion: Dual-echo MRI, MRS, and CT LAI are accurate measures to quantify the degree of hepatic steatosis in LDLT donors, thus reducing the need for invasive liver biopsy and its associated complications. Dual-echo MRI and MRS results correlate better with histological results in the study, as compared to CT LAI method for fat quantification