A New Bioanalytical Method Development & Validation for Simultaneous Estimation of Esomeprazole and Naproxen in Human Plasma by Using RP-HPLC.

Aim: A new reverse phase high performance liquid chromatography (RP-HPLC) method for the quantitative determination of Esomeprazole and Naproxen in human plasma was developed and validated as per US-FDA guidelines. Methodology: The drug was spiked in the plasma and extracted with mobile phase by precipitation method. The extracted analyte was injected into Symmetry C18 (4.6 x 150mm, 5μm, Make: XTerra) or equivalent, maintained at ambient temperature and effluent was monitored at 285nm. The mobile phase was composed of potassium dihydrogen phosphate and acetonitrile [HPLC Grade] in the ratio of 60:40. The pH of the potassium buffer was adjusted to 3.0 by using Ortho Phosphoric Acid. The flow rate was maintained at 1.0 mL/min. Results: The developed method shows high specificity for Esomeprazole and Naproxen. The calibration curve for Esomeprazole and Naproxen was linear from 1.0 to 6.0 ppm (r2= 0.999) and 25.0 to 150.0 ppm (r2= 0.999) respectively. The inter-day and intra-day precision was found to be within limits. The proposed method was adequate sensitivity, reproducibility, and specificity for the determination of esomeprazole and naproxen in plasma. The Lower limit of quantification (LLOQ) for the drug Esomeprazole and Naproxen were found to be 0.04μg/ml and 0.4μg/ml respectively. The average percent recovery for the drugs Esomeprazole and Naproxen were found to be 98.97-99.84 & 99.80-100.95 respectively and reproducibility was found to be satisfactory. Conclusion: The proposed method was accurate, and precise for the quantification of Esomeprazole and Naproxen in the plasma. The proposed can also be used for routine analysis in quality control. The method was validated for parameters like selectivity, sensitivity, precision, intermediate precision, accuracy, linearity, recovery & stability. This RP -HPLC method is suitable for determining the concentration of Esomeprazole and Naproxen in plasma and it can applied for routine analysis for determination of the Esomeprazole and Naproxen from dosage form during pharmacokinetic study.

Effect of fenvalerate technical grade on acetyl cholinesterase activity in Indian bullfrog Haplobatrachus tigerinus (Daudin).

Indian bullfrog Haplobatrachus tigerinus (Daudin) was exposed to sublethal dose (1/3 of LC50 I.E. 1.166 mg/kg) of fenvalerate technical grade and the effect was studied on the specific activity of acetyl cholinesterase in the different tissues of frog viz., brain, muscle, liver, kidney and testis at different time periods viz., 3,6, 12, 24, 48 and 72 hours. The inhibition of specific activity of acetyl cholinesterase was in the order of kidney > brain > muscle > liver > testis. A significant inhibition was noticed in kidney at 12 hours (-64.33%) and no effect was noticed at 3 hours in testis (+0.67%). The AChE activity was inhibited in first three hours of administration of fenvalerate in all the tissue tested. The inhibition continued upto 6 hours or 2 hours in different tissue but the recovery was started by 24 hours and almost completed by 72 hours.

Micropropagation of Sapindus mukorossi Gaertn.

Bud break and multiple shoots were induced in apical and axillary meristems derived from one month old seedlings of S. mukorossi on Murashige and Skoog (MS) medium supplemented with benzylamino purine (BAP) 0.4 microM or 0.8 microM alone. A combination of BAP and gibberellic acid (GA3) 0.4 microM and 2.8 microM produced elongated multiple shoots from both types of explants. Excised shoots were rooted on MS medium respectively with indole-3-butyric acid (IBA) 3.4 microM or 2.4 microM. The regenerated plantlets were successfully acclimatized and transferred to soil.

Modulatory effect of sepia shell extract on activity of glucose-6-phosphatase and alanine amino transferase in diabetic mice.

Alkali extract of sepia shell possesses hypoglycemic effect. The status of glycogen and pyruvate and the activity of glucose-6-phosphatase and alanine amino transferase in liver was studied under the influence of sepia shell extract in both normal and streptozotocin induced diabetic mice. The glycogen concentration was elevated steeply in both and the pyruvate concentration increased substantially in diabetic mice, while the activity of glucose-6-phosphatase and alanine amino transferase was inhibited in normal and diabetic mice. The sepia shell extract enhances glycogenesis and reduces the formation of glucose from metabolic intermediates like pyruvate and glucose-1-phosphate and by suppressing gluconeogenesis.

Chronopharmacokinetics of rifampicin.

Chronopharmacokinetics of rifampicin was studied in four healthy adult male human volunteers after drug (2.0 g) ingestion at 6.00, 12.00, 18.00 and 24.00 hr. The absorption rate constant was found to be lower and the time to reach peak concentration was longer after drug administration at 24.00 hr than at other dosing times. A second peak was observed in all individual volunteers between 6-12 hr after drug dosing at 24.00 hr. This may be due to the influence of biliary rhythms on the disposition kinetics of rifampicin.