Lila Kanta Nath

Evaluation of acetylated moth bean starch as a carrier for controlled drug delivery.

Highlights ► Hydrophobic polymers are extensively used as matrix former in controlled drug delivery. ► We have synthesized a new hydrophobic polymer using acetylation of native moth bean starch. ► The hydrophobic polymer was evaluated as controlled release excipient for pharmaceutical formulation development. ► The results revealed that the acetylated moth bean starch can be used as controlled release polymer.

Evaluation of compatibility of tablet excipients and novel synthesized polymer with lamivudine

The present study describes compatibility of anti-HIV drug lamivudine with various selected excipients and a novel synthesized polymer, for the development of its controlled release formulation. Differential scanning calorimetry (DSC), isothermal stability study (ISS) and Fourier transform infrared (FT-IR) spectral analysis were performed to access the compatibility. The compatibility study was performed with various common excipients like spray dried lactose, polyvinyl pyrrolidine K-30, magnesium stearate, talc and a novel synthesized polymer cross-linked sago starch with lamivudine.

Compatibility studies of nateglinide with excipients in immediate release tablets.

Compatibility studies of nateglinide with excipients in immediate release tablets Experiments were done to assess the compatibility of nateglinide with selected excipients in the development of immediate release tablets of nateglinide by thermal and isothermal stress testing (IST) techniques. To evaluate the drug-excipient compatibility, different techniques such as differential scanning calorimetric (DSC) study, infra-red (IR) spectrophotometric study and isothermal stress testing were adopted. The results of DSC study showed that magnesium stearate exhibited some interaction with nateglinide. However, the results of IR, and IST studies showed that all the excipients used in the formula were compatible with nateglinide. Optimized formulations developed using the compatible excipients were found to be stable over 3 months of accelerated stability studies (40 ± 2°C and 75 ± 5% RH). Overall, compatibility of excipients with nateglinide was successfully evaluated using a combination of thermal and IST methods and the formulations developed using the compatible excipients were found to be stable. Ispitivanje kompatibilnosti nateglinida s pomoćnim tvarima u razvoju tableta nateglinida za trenutno oslobađanje Koristeći termičke metode kao što su diferencijalna pretražna kalorimetrija (DSC) i infra-crvena spektrofotometrija (IR), te izotermička stres-testiranja (IST) ispitana je kompatibilnost nateglinida s izabranim ekscipiensima u razvoju tableta nateglinida za trenutno oslobađanje. Rezultati DSC ispitivanja pokazala su da magnezijev stearat stupa u određenu interakciju s nateglinidom. Međutim, IR i IST ispitivanja pokazuju da su svi upotrijebljeni ekscipiensi kompatibilni s nateglinidom. Optimirana formulacija bila je stabilna preko 3 mjeseca u testovima ubrzanog starenja (40 ± 2°C i 75 ± 5% RH). Kompatibilnost ekscipiensa s nateglinidom uspješno je evaluirana koristeći kombinaciju termičke i IST metode, a formulacije razvijene koristeći kompatibilne ekscipiense bile su stabilne.

Synthesis and evaluation of physicochemical properties of cross-linked sago starch.

Highly substituted sago starch phosphate was synthesized using POCl(3) as cross-linking reagent. Titrimetric and Fourier transform infra red (FT-IR) spectral analysis were used to characterize the substitution. Studying the different factors affecting the reaction parameters showed that the optimal conditions for starch phosphorylation were: 4h reaction time and reagent concentration 1.5% (w/w). The physicochemical properties of cross-linked sago starch (CLSS) were done using Scanning electron micrograph (SEM), X-ray powder diffractometer (XRD and Thermogravimetric analysis (TGA). The results revealed that crystalline nature of native sago starch was transformed after cross-linking. TGA report exhibited higher thermal stability, which makes it suitable for various industrial applications. Swelling behavior showed high swelling at low temperature (30 and 60°C) as compared to high temperature (90°C).

Development and validation of analytical method for the estimation of lamivudine in rabbit plasma

Lamivudine has been widely used in the treatment of HIV disease. A reliable, sensitive reversed phase high performance liquid chromatography (RP-HPLC) method was developed and validated for lamivudine in rabbit plasma. The method was developed on Hypersil BDS C-18 column (250 mm×4.6 mm, 5 μm) using a mobile phase of 0.25% Triethylamine buffer (pH 3.0): acetonitrile (70:30, v/v). The efficient was monitored by UV detector at 256 nm. The total run time was 15 min with a flow rate of 1.0 mL/min. Calibration curve was linear over the concentration range of 25–2000 ng/mL. The retention times of lamivudine and internal standard (Nelfinavir) were 8.78 min and 10.86 min, respectively. The developed RP-HPLC method can be successfully applied for the quantitative pharmacokinetic parameters determination of lamivudine in rabbit model.

Synthesis, characterization, and compatibility study of acetylated starch with lamivudine

In this study, highly substituted starch acetate was prepared by reaction with native moth bean starch and acetic anhydride. Physicochemical characterization of this modified starch was done using scanning electron microscopy, X-ray diffraction, and thermogravimetric analysis. Their formation was confirmed by titrimetric analysis and highest degree of substitution was observed with a value of 2.35. The synthesized modified starch was further studied for compatibility with model drug lamivudine using differential scanning calorimetry and isothermal stress testing for its controlled release tablet formulation.

Formulation and in vitro evaluation of metformin hydrochloride loaded microspheres prepared with polysaccharide extracted from natural sources

The present work envisages utilisation of biodegradable and biocompatible material from natural sources for the development of controlled release microspheres of metformin hydrochloride (MetH). Natural polysaccharides extracted from Dillenia indica L. (DI), Abelmoschus esculentus L. (AE) and Bora rice flour were used in fabricating controlled release microspheres. The microspheres were prepared by the emulsion solvent diffusion technique with different proportions of natural materials and were studied for entrapment efficiency, particle size, particle shape, surface morphology, drug excipient compatibility, mucoadhesivity and in vitro release properties. The prepared microspheres showed mucoadhesive properties and controlled release of metformin hydrochloride. The study has revealed that natural materials can be used for formulation of controlled release microspheres and will provide ample opportunities for further study

Evaluation of chemically modified hydrophobic sago starch as a carrier for controlled drug delivery

The present investigation deals with the development of controlled release tablets of lamivudine using acetylated sago starch. The acetylated starch was synthesized with acetic anhydride in pyridine medium. The acetylated sago starch was tested for acute toxicity and drug-excipient compatibility study. The formulations were evaluated for physical characteristics like hardness, % friability, % drug content and weight variations. The in vitro release study showed that the optimized formulation exhibited highest correlation (R) value in the case of higuchi kinetic model and the release mechanism study proved that the formulation showed a combination of diffusion and erosion processes. There was a significant difference in the pharmacokinetic parameters (T max, C max, AUC, V d, T 1/2 and MDT) of the optimized formulation as compared to the marketed conventional tablet Lamivir® which proves the controlled release property of acetylated sago starch.

Development of controlled release tablet by optimizing HPMC: Consideration of theoretical release and RSM

The objective of the study was to develop controlled release tablets of nateglinide, a meglitinide derivative anti-diabetic drug, considering theoretical release profile and response surface methodology (RSM). 3(2) factorial design was utilized to optimize concentration of hydroxylpropylmethylcellulose (HPMC) K15M and K100M to obtain the desired responses (drug release at one and six hours). Theoretical release profile of drug for controlled release formulation was calculated and considered as reference for the determination of similarity factor (f2) and desimilarity factor (f1). RSM, f2 and f1 were used to select the optimum formulation. Formulation containing HPMC K15M (5%) and HPMC K100M (15%) was found optimum with desired responses with f2=86.05 and drug release profile followed zero order kinetics. Excipients used were compatible with drug, confirmed initially through DSC and IST study. The optimization of experiments was validated and optimum formulation was passed the stability study.

Evaluation of microwave assisted grafted sago starch as controlled release polymeric carrier

In the present investigation an attempt has been made to develop a new co-polymeric material for controlled release tablet formulations. The acrylamide grafting was successfully performed on the backbone of sago starch. The modified starch was tested for acute toxicity and drug-excipient compatibility study. The grafted material was used in making of controlled release tablets of lamivudine. The formulations were evaluated for physical characteristics such as hardness, friability, %drug content and weight variations. The in vitro release study showed that the optimized formulation exhibited highest correlation (R) value in case of Higuchi model and the release mechanism of the optimized formulation predominantly exhibited combination of diffusion and erosion process. There was a significant difference in the pharmacokinetic parameters (T(max), C(max), AUC, V(d), T(1/2) and MDT) of the optimized formulation as compared to the marketed conventional tablet Lamivir(®) was observed. The pharmacokinetics parameters were showed controlled pattern and better bioavailability. The optimized formulation exhibited good stability and release profile at the accelerated stability conditions.