Simultaneous Spectrophotometric Method for Determination of Emtricitabine and Tenofovir Disoproxil Fumarate in Three-Component Tablet Formulation Containing Rilpivirine Hydrochloride.

Developing a single analytical method for estimation of individual drug from a multidrug composition is a very challenging task. A complexation, derivatization, extraction, evaporation, and sensitive-free direct UV spectrophotometric method is developed and validated for the simultaneous estimation of some antiviral drugs such as emtricitabine (EMT), tenofovir disoproxil fumarate (TDF), and rilpivirine HCl (RPV) in tablet dosage form by Vierordt's method. The solutions of standard and sample were prepared in methanol. The λ max⁡ for emtricitabine, tenofovir disoproxil fumarate, and rilpivirine hydrochloride were 240.8 nm, 257.6 nm, and 305.6 nm, respectively. Calibration curves are linear in the concentration ranges 4-12 µg/ml for EMT, 6-18 µg/ml for TDF, and 0.5-1.5 µg/ml for RPV, respectively. Results of analysis of simultaneous equation method were analyzed and validated for various parameters according to ICH guidelines.

Stability-Indicating HPLC Method for the Simultaneous Determination of HIV Tablet Containing Emtricitabine, Tenofovir Disoproxil Fumarate, and Rilpivirine Hydrochloride in Pharmaceutical Dosage Forms.

A simple, accurate, rapid, and stability-indicating RP-HPLC method for a combination of tenofovir disoproxil fumarate, emtricitabine, and rilpivirine has been developed and subsequently validated in commercial tablets. The proposed HPLC method utilizes Phenomenex Gemini C18 column (150 mm × 4.6 mm i.d., 5 µm) and mobile phase consisting of MeCN, potassium dihydrogen phosphate buffer (20 mM, pH 3.3), and triethylamine 58.72 : 41.23 : 0.05 (v/v) at a flow rate of 1.7 mL/min. Quantitation was achieved with UV detection at 270 nm. The method was validated in terms of accuracy, precision, linearity, limits of detection, limits of quantitation, and robustness. This optimized method has been successively applied to pharmaceutical formulation and no interference from the tablet excipients was found. TDF, EMT, and RPV and their combination drug product were subjected to acid, base, neutral hydrolysis, oxidation, dry heat, and photolytic stress conditions and the stressed samples were analyzed by the proposed method. As the proposed LC method could effectively separate the drugs from its degradation products, it can be employed as stability-indicating method for the determination of instability of these drugs in bulk and commercial tablets.

Phytochemical, anti-oxidant and Anthelmintic activities of various leaf extracts of Flacourtia sepiaria Roxb.

OBJECTIVE: The present study was carried out to investigate the phytochemical constituents, In vitro antioxidant potential and anthelmintic activities of Flacourtia sepiaria Roxb leaves. METHODS: The dried powdered leaves of Flacourtia sepiaria were extracted using petroleum ether, chloroform, ethyl acetate and methanol by a soxhlet extractor and preliminary phytochemical screening was performed using standard protocols. All the extract was evaluated for their potential antioxidant activities using test such as DPPH, superoxide anion radical, hydroxyl radical, nitric oxide radical scavenging abilities, ferrous chelating ability and total phenolic and flavanoid content. Anthelmintic activity of extract was screened in adult Indian earthworm model. RESULTS: Preliminary screening revealed the presence of bioactive compounds especially phenolics, tannins and terpenoids in all extracts. The phenolic and flavanoid content was highest in methanolic extract and lowest in petroleum ether extract. The paralytic (9.46±0.212) and death time (31.43±0.148) of methanolic extract was found to be significant (P<0.05) when compared with paralytic (7.33±0.206) and death time (18.60±0.229) of standard piperazine citrate at 100 mg/mL concentration. CONCLUSIONS: The results of the present study indicate that the leaf extracts of Flacourtia sepiaria exhibited strong antioxidant activity and possess significant anthelmintic activity and thus it is a good source of antioxidant and anthelmintic constituents.

Sustaining pattern of phenformin hydrochloride using various polymers and waxes.

The present study was carried out to formulate matrix tablets of phenformin hydrochloride. Granules of phenformin HCl were prepared by using ethyl cellulose, eudragit RS 100, gum acacia, carnauba wax, stearyl alcohol, glyceryl monostearate and triethanol amine. Thus the granules were compressed and fourteen tablets formulations were prepared. All the physical parameters of granules and matrix tablets were studied including compatibility study. One commercial timed disintegration capsule was also included for study and comparison. The results of in vitro studies showed that sustained release matrix tablet might be prepared using carnauba wax, stearyl alcohol, triethanol amine and magnesium stearate.