Anindita Behera

Method development, validation and stability study of ritonavir in bulk and pharmaceutical dosage form by spectrophotometric method

Background: Ritonavir is a protease inhibitor and mostly used as a booster for increasing the bioavailability of other protease inhibitors like Atazanavir Sulfate and Lopinavir. Aims: Quality assessment of the new dosage form of Ritonavir i.e. tablets is very essential, so two sensitive, simple and precise methods are developed for quantification of Ritonavir in bulk and tablet dosage forms. Materials and Methods: The first method is based on first order derivative method and the second is based on area under curve method. Both the methods are validated according to international conference of harmonization (ICH) guidelines. A stability study of Ritonavir is done in UV - Visible Spectrophotometer under different stress conditions recommended by ICH guidelines. Results: The absorption maximum is found to be 239nm in methanol. The absorption maximum in first method is chosen at 253.2nm, and the linearity is found between 4 - 20 ΅g/ml with coefficient of correlation value 0.9981. In the second method, the range for area under curve selected is 237 - 242nm. The linearity is found between 4 -20 ΅g/ml with coefficient of correlation value 0.9992. Conclusion: The developed methods are validated and found to be simple, rapid, precise and cost-effective. The degradation study in tablet dosage form can be used as a stability indicating assay method.

STATISTICAL CORRELATION AND SIMULTANEOUS ESTIMATION OF ATAZANAVIR SULFATE AND RITONAVIR IN FIXED DOSAGE FORM BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY AND HIGH PERFORMANCE THIN LAYER CHROMATOGRAPHY

Two chromatographic methods are developed and validated to estimate Atazanavir Sulfate and Ritonavir in new fixed dosage form, that is, tablet dosage form named Synthivan. The first method is based on HPLC separation of the two drugs on the reversed phase HiQSil C18 column (5 µm, 250 × 4.6 mm) at ambient temperature using an isocratic solvent system consisting of acetonitrile and water in the ratio 52:48 (v/v). Quantification is achieved with a PDA detector at 254 nm at a flow rate of 1.5 mL/min. Linearity of concentrations is found at 60–600 µg/mL and 20–200 µg/mL for Atazanavir sulfate and ritonavir, respectively. The second method is based on HPTLC separation of the two drugs on pre-coated silica gel 60F254 aluminum plates using toluene:methanol:glacial acetic acid:ethyl acetate (7:0.5:1.5:2, v/v/v/v) as solvent system followed by densitometric measurements of their spots at 254 nm. The linearity of the concentration is found to be 30–300 and 10–100 ng/spot for Atazanavir Sulfate and Ritonavir, respectively. Both methods are validated according to ICH guidelines. The analysis of variance (ANOVA) and Students t-test are applied to correlate the results of Atazanavir Sulfate and Ritonavir determination in dosage form by means of HPLC and HPTLC method.

Spectrophotometric method for determination of atazanavir sulfate in capsule dosage form

1used in the treatment of human immunodeficiency virus (HIV) Type II infection. ATV is re ported as poorly water soluble and a known substrate for both hepatic metabolizing enzyme Cytochrome 450 (CYP3A) and intestinal drug efflux pump, P-glycoprotein (Pgp) so have low oral bioavailability. 2 So co-administration of small dose of Ritonavir (RTV) is recommended as booster. This new drug is official in IP - 2010, but not included in BP or USP. The reported analytical methods for the determination of ATV are based on high performance liquid chromatography (HPLC) 3-12 in biological samples like blood plasma, biological cells, cerebrospinal fluid (CSF) and blood serum. Stress degradation studies were reported analysed by HPLC and ultraviolet spectrophotometry. 13, 14 The present work was aimed to develop a visible spectrophotometric method, which is simple, sensitive, accurate and cost effective to evaluate the quality of the bulk and pharmaceutical formulations. The novelties of the developed methods are that the reagents used in both the methods are easily available and the mechanisms of reactions of the reagents are already well established. The reactions involved with these reagents are simple, rapid and sensitive. Spectrophotometric methods involve simple instrumentation which is cost effective as compared to other instrumental techniques. The present method involves the determination of ATV, which is a second line drug for treatment of type II HIV infection. Still now, the 2 nd line drugs are available at higher price, than the 1 st line drugs. The high

Preparation and mechanistic aspect of natural xanthone functionalized gold nanoparticle

Herein, a facile scale up and shape variable synthesis of gold nanoparticle (AuNP) and reaction mechanism by natural xanthone derivative (mangiferin) has been reported. Mangiferin (C19H18O11; 1,3,6,7-tetrahydroxyxanthone-C2-β-d-glucoside), a xanthone derivative is isolated from Mangifera indica L. leaves which efficiently reduces Au3+ ions to Au0 and stabilizes the formed AuNP. The structural, optical and plasmonic properties of synthesized AuNP have been investigated through different instrumental techniques like UV-Vis and FTIR spectroscopy, powder XRD, FESEM and TEM analysis. It is observed that variation of the concentration of Au3+ ions and mangiferin has a great effect on controlling size and shape of nanoparticles. The role of reaction temperature is also notable. An interesting observation is that with same concentration ratio of HAuCl4/mangiferin (0.025 mM/0.002%) at the room temperature kidney shaped AuNP is produced, whereas it is spherical at boiling temperature. Moreover, mangiferin allows high scale synthesis of AuNPs (0.025 mM to 10 mM) without changing the particles size and shape. The mechanistic investigation through UV-Vis, FTIR and GCMS analyses reveal the cleavage of glucose unit and oxidation of phenolic OH groups during AuNP formation. Non-toxicity of mangiferin conjugated AuNP on normal human breast cell line (MCF-10A) suggesting its future application as a drug delivery system and other related medicinal purposes.

Green synthesis of multi-metallic nanocubes

A facile synthetic route and growth mechanism of heterobimetallic cubical nanoparticles Au@AgCl and Ag@AgCl@Au have been developed using Muntingia calabura flower extract. The formation of nanoparticles has been confirmed through UV-Vis, powder X-ray diffraction and electron microscopy. The elemental composition of the nanoparticles has been evidenced by EDS analysis. Combing the UV-Vis spectral analysis and powder X-ray diffraction studies, the composition of bimetallic nanoparticles are assigned as Au@AgClNP and Ag@AgCl@AuNP. The prepared nanoparticles display good antibacterial activity which is comparable to standard kanamycin and ampicillin.

Comparative study of chromatographic, spectrophotometric and non aqueous titrimetric methods for determination of protease inhibitor in tablets

The paper describes HPLC, UV spectrophotometric and non aqueous titrimetric method for the estimation of poorly water soluble protease inhibitor. Ritonavir in raw material and tablet dosage form. HPLC analysis was carried out in a C18 column using acetonitrile, methanol, and buffer in the ratio 60: 20: 20 (v/v/v) at 240 nm. For the spectrophotometric determination, methanolic solution of Ritonavir was reacted with 3-methyl benzothiazolin-2-one hydrazone (MBTH). The oxidative coupled green coloured chromogen was analysed at 633 nm. Non aqueous titration was carried out using perchloric acid as titrant and the end point was determined using crystal violet as indicator. The three methods were validated and statistically evaluated to correlate the difference between the methods for estimation of Ritonavir in pharmaceutical dosage form.

Densitometric thin-layer chromatography of protease inhibitors in pharmaceutical preparations

Atazanavir sulfate (ATV) (3S,8S,9S,12S)-3,12-bis(1,1dimethylethyl)-8-hydroxy-4,11-dioxo-9-(phenylmethyl)-6-[[4(2-pyridinyl)phenyl]methyl]-2,5,6,10,13-pentaazatetradecanedioic acid dimethyl ester(Figure 1), an azapeptide, is the 7th protease inhibitor used in the treatment of human immunodeficiency virus (HIV) Type II infection [1]. ATV is reported as poorly water soluble and a known substrate for both hepatic metabolizing enzyme Cytochrome 450 (CYP3A) and intestinal drug efflux pump, P-glycoprotein (Pgp), so it has low oral bioavailability [2]. In literature, several methods of analysis are reported for determination of ATV in blood plasma, biological cells, and cerebrospinal fluid by high-performance liquid chromatography (HPLC) [3–12]. Stress degradation studies were reported and analyzed by HPLC and ultraviolet spectrophotometry [13, 14].