Akhilesh V. Singh

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.

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.

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 and validation of analytical method for the estimation of nateglinide in rabbit plasma

Nateglinide has been widely used in the treatment of type-2 diabetics as an insulin secretogoga. A reliable, rapid, simple and sensitive reversed-phase high performance liquid chromatography (RP-HPLC) method was developed and validated for determination of nateglinide in rabbit plasma. The method was developed on Hypersil BDSC-18 column (250 mm×4.6 mm, 5 mm) using a mobile phase of 10 mM phosphate buffer (pH 2.5) and acetonitrile (35:65, v/v). The elute was monitored with the UV–vis detector at 210 nm with a flow rate of 1 mL/min. Calibration curve was linear over the concentration range of 25–2000 ng/mL. The retention times of nateglinide and internal standard (gliclazide) were 9.608 min and 11.821 min respectively. The developed RP-HPLC method can be successfully applied to the quantitative pharmacokinetic parameters determination of nateglinide in rabbit model.

Evaluation of Trapa bispinosa Roxb. Starch as Pharmaceutical Binder in Solid dosage form

Article history: Objective: This study was undertaken, to evaluate binding efficiency of Trapa bispinosa Roxb. starch (TBS) in Diclofenac sodium tablets.Methods: Diclofenac sodium tablets were prepared using wet granulation method. The starch paste in different concentrations (5-15%w/w) was evaluated for optimized binder concentration. Preformulation study of the drug with TBS and different excipients were also analyzed using Fourier transform infra red spectroscopy (FT-IR) and Isothermal stress testing (IST). Results: Preformulation study of the drug, water chestnut starch and different excipients showed no interaction or, drug degradation in FTIR and IST respectively. The tablets were evaluated for hardness, friability, drug content, disintegration and dissolution studies, and all the parameters were found within the official specifications. Conclusion: The results revealed that this starch has potential to be used as binder at industrial scale in pharmaceutical solid dosage form development.

Microwave Assisted Synthesis and Evaluation of Modified Pea Starch as Tablet Superdisintegrant

In the present study, cross linked sodium carboxymethylated pea starch (SCPS) was synthesized and evaluated as tablet superdisintegrant in diclofenac sodium based tablets. SCPS was synthesized using native pea starch with monochloroacetic acid and NaOH in microwave radiation environment. Finally the dried product was cross-linked with phosphorous oxychloride, which produced granular highly swellable starch. SCPS with degree of substitution of 0.34 was formed and it was further evaluated as superdisintegrant in diclofenac sodium based tablets. Diclofenac sodium tablets were prepared by direct compression method with 2, 4, 6 and 8%w/w of SCPS as superdisintegrant and further comparatively evaluated for in vitro disintegration and dissolution study with Sodium starch glycolate containing tablets as reference. The results revealed that SCPS could be a promising superdisintegrant for immediate release tablets in concentration dependant manner.

Evaluation of orlistat solid dispersion using poloxomer 188 as hydrophilic carrier

Objective: The objective of the present investigation was to improve the dissolution rate of Orlistat (ORL), a poor water-soluble anti-obesity drug by solid dispersion technique. Materials and Methods: To improve the solubility and dissolution, ORL solid dispersion was formulated using a hydrophilic polymeric carrier poloxomer 188. Solid dispersion was formulated by kneading method and physicochemical characterization and in vitro release study was carried out. Results: Fourier transform infrared spectral (FT-IR) and Differential scanning calorimetry (DSC) study showed a change in the crystalline nature of the drug, and its conversion into amorphous form. The in vitro dissolution study of physical mixture and solid dispersion both showed enhanced solubility as compared to the pure active drug. Conclusion: This study suggests that ORL solid dispersion having drug: Carrier (1:5) could be a promising approach to improve the solubility and dissolution.