Prakash V Diwan

The neem tree has been known for its unique properties both in improving human health and against insects. Azadirachtin is a tri terpenoid limonoid obtained from various parts of the neem. Phosphatidyl choline is the most important phospholipid which helps in crossing the lipid barrier of the cell membrane and thus helps in easy absorption of the compound/drug. In the present work we are combining the isolated Azadirachtin and PC to form a complex, which can enhance the bio availability and easy absorption of the compound/drug. First of all, Azadirachtin is extracted from the dried neem kernel powder in a Soxhlet extractor using Di-Chloro methane as a solvent. Phosphatidyl choline is extracted and isolated from soya lecithin oil through reflux, using Methanol + Sodium hydroxide as solvent. The TLC, UV, HPLC, FTIR and DSC reports indicate the separation of the compounds from their crude forms. Azadirachtin and Phosphatidyl choline separated are refluxed together for 2 hours and dried in a Rota evaporator to form a 'Complex'. The absorbance's of Azadirachtin, Phosphatidyl choline and the Complex are measured at 220, 230 and 217nm. The qualitative analysis of Azadirachtin, Phosphatidyl choline and the Complex (1:1) were carried out by HPLC, on a C-18 column. Aceto nitryl: Methanol: 1% Triethyl amine pH 4 (60:40:1) was used as mobile phase at a flow rate of 1ml/min, at 210nm.The isolation of Phosphatidyl choline from soya lecithin oil used is a new method and the formation of Complex is an innovative work.

A simple, precise, accurate and stability-indicating reverse phase high performance liquid chromatography (RP-HPLC) method is developed for estimation of Isosorbide 5-Mononitrate in bulk drug and tablet dosage form. The method employed, with reverse phase phenomenex® Luna 5µ C18 (2) 100A (250 × 4.60 mm) column in an isocratic mode, with mobile phase of methanol: water: acetonitrile in the ratio 55:28:17 (%v/v/v). The flow rate was 1.0 ml/min and effluent was monitored at 217 nm. Retention time was found to be 4.391±0.015 min. The method was validated in terms of linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ) etc. in accordance with ICH guidelines. Linear regression analysis data for the calibration plot showed that there was good linear relationship between response and concentration in the range of 1- 9 µg/ml respectively. The LOD and LOQ values for were found to be 2.5 and 10 ng/ml respectively. No chromatographic interference from tablet excipients and degradants were found. The proposed method was successfully used for estimation of Isosorbide 5-Mononitrate in tablet dosage form.

A simple, accurate, economical and reproducible reverse phase high performance liquid chromatographic (RP-HPLC) method was developed and validated for the determination of Cetirizine hydrochloride and Ambroxol hydrochloride in bulk and pharmaceutical formulations. The separation was achieved on a phenomenex C18 column (150 × 4.6 mm i.d, particle size of 5µ) using a mixture of methanol, acetonitrile and water in the ratio of (30:30:40v/v )as mobile phase in an isocratic elution mode, at a flow rate of 1  ml/min. The detection was monitored at 230 nm. The retention time of Cetirizine hydrochloride and Ambroxol hydrochloride was found to be around 2.27 ± 0.12 min and 4.70 ± 0.14 min respectively. Excellent linearity range was found between 1-10 µg/ml for cetirizine hydrochloride and 10-100 µg/ml for Ambroxol hydrochloride. The method was validated with respect to linearity, robustness, precision and accuracy and was successfully applied for the simultaneous determination of Cetirizine hydrochloride and Ambroxol hydrochloride from the combined dosage formulation. Key words: Cetirizine hydrochloride; Ambroxol hydrochloride; RP-HPLC method.