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Objective: Sitagliptin phosphate and metformin hydrochloride tablet is an FDA approved combination product for the treatment of diabetes mellitus type 2. There are no reported evidence for estimation of undesired (S)-sitagliptin in a combination product. The objective of this study was to develop a high sensitive liquid chromatography method for the determination of (S)-enantiomer of sitagliptin phosphate in a fixed dose combination formula of metformin and sitagliptin. Methods: The proposed novel high-performance liquid chromatography (HPLC) method uses programmed gradient elution of a mixture of ethanol-diethylamine(DEA) 100:0.1 (v/v) as mobile phase-A and a mixture of methanol-water 60:40 (v/v) as mobile phase-B. The chromatographic conditions were designed to nullify the metformin interference and in which sitagliptin enantiomers elute first and followed by metformin. A satisfactory resolution (≥2.5) between (S)-sitagliptin and active form (R)-sitagliptin was achieved with gradient elution on Chiralpak IA column (5μm, 4 × 250 mm) at a flow rate of 0.5 ml/min and the detector wavelength set at 265 nm. The injection volume set as 10 µl. The developed method has been validated as per the International Conference on Harmonisation (ICH) guidelines. Results: The proposed HPLC method for determination of (S)-sitagliptin, showed good linearity in the concentration range of 0.5 µg/ml to 13.6 µg/ml and capable to quantify accurately up to the lowest level (LOQ) of 0.017%. The validated method was successfully applied to quantify the (S)-sitagliptin for different marketed formulations of sitagliptin with metformin and sitagliptin alone, and the corresponding recovery values were found to be in the range of 95.1% to 98.4%. Conclusion: The proposed validated HPLC method was found to be suitable for the quantitative determination of (S)-sitagliptin in the formulations of sitagliptin with metformin and sitagliptin alone.

Aims: Carvedilol phosphate (CDP) is a nonselective beta-blocker used for the treatment of heart failures and hypertension. In this work, moisture sorption–desorption characteristics and thermodynamic properties of CDP have been investigated. Materials and Methods: The isotherms were determined using dynamic vapor sorption analyzer at different humidity conditions (0%–90% relative humidity) and three pharmaceutically relevant temperatures (20°C, 30°C, and 40°C). The experimental sorption data determined were fitted to various models, namely, Brunauer–Emmett–Teller; Guggenheim-Anderson-De Boer (GAB); Peleg; and modified GAB. Isosteric heats of sorption were evaluated through the direct use of sorption isotherms by means of the Clausius-Clapeyron equation. Statistical Analysis Used: The sorption model parameters were determined from the experimental sorption data using nonlinear regression analysis, and mean relative percentage deviation (P), correlation (Correl), root mean square error, and model efficiency were considered as the criteria to select the best fit model. Results: The sorption–desorption isotherms have sigmoidal shape – confirming to Type II isotherms. Based on the statistical data analysis, modified GAB model was found to be more adequate to explain sorption characteristics of CDP. It is noted that the rate of adsorption and desorption is specific to the temperature at which it was being studied. It is observed that isosteric heat of sorption decreased with increasing equilibrium moisture content. Conclusions: The calculation of the thermodynamic properties was further used to draw an understanding of the properties of water and energy requirements associated with the sorption behavior. The sorption–desorption data and the set of equations are useful in the simulation of processing, handling, and storage of CDP and further behavior during manufacture and storage of CDP formulations.

Aim Intend of the present exertion is to prepare β-cyclodextrin (β-CD) based polymeric nanosuspension (PNS) of Efavirenz (EFV) with enhanced aqueous solubility and dissolution rate as compared to pure drug. Background EFV is a low aqueous soluble molecule because of which there is drug absorption problem. To overcome this problem polymeric nanosuspension were prepared using precipitation method which produced successful results. Materials and methods Four formulations (β-CDPNS1, β-CDPNS2, β-CDPNS3 and β-CDPNS4) with varying drug-polymer ratios were prepared by precipitating drug-polymer physical mixtures dissolved in organic phase in an aqueous phase. Solid state characterization of β-CDPNS's were conducted using X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy-universal attenuated total reflectance (FTIR-UATR), and scanning electron microscopy (SEM) to examine physical properties and to study the compatibility of EFV with pharmaceutical excipients. Dynamic light scattering (DLS) studies was performed for nanoparticles evaluation. Results The mean diameter of the nanoparticles ranged between 143.8 and 284.4 nm and polydispersity index (Pdi) values for all the nanosuspensions were small ( 60% in each formulation. Conclusion Successful preparation and characterization of Efavirenz nanosuspension by solvent injection method has been accomplished in this study.

Efavirenz is a non-nucleoside reverse transcriptase inhibitor used in the treatment of human immunodeficiency virus type-1 (HIV). (2S)-(2-Amino-5-chlorophenyl)-4-cyclopropyl-1,1,1-trifluoro-3-butyn-2-ol (AMCOL), used as an intermediate in the synthesis of efavirenz and a degradation impurity, has an aminoaryl derivative which is a well-known alerting function for genotoxic activity. Upon request from a regulatory agency, a selective and sensitive liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed for trace level quantitative determination of AMCOL related compound of efavirenz, for a risk assessment and comparison of impurity levels with the commercially available innovator product (brand name: Sustiva). The method provided excellent sensitivity at a typical target analyte level of &lt, 2.5 ppm, an established threshold of toxicological concern (TTC), when the drug substance and drug product samples were prepared at 15.0 mg/mL. The AMCOL sample was analyzed on a Luna C18 (2) (100 mm × 4.6 mm, 3 µm) column interfaced with a triple quadrupole tandem mass spectrometer operated in a multiple reaction monitoring (MRM) mode. Positive electrospray ionization (ESI) was employed as the ionization source and the mobile phase used was 5.0 mM ammonium acetate-methanol (35:65, v/v). The calibration curve showed good linearity over the concentration range of 0.2–5.0 ppm with a correlation coefficient of &gt, 0.999. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.07 and 0.2 ppm, respectively. The developed method was validated as per international council on harmonization (ICH) guidelines in terms of LOD, LOQ, linearity, precision, accuracy, specificity, and robustness.

Purpose: To enhance the aqueous solubility and dissolution rate of elvitegravir (EVG) by formulating the drug as solid lipid nanoparticles (SLNs) using solvent injection method.Methods: EVG-loaded SLNs were prepared by solvent injection method. Four different formulations of SLN were prepared using gelucire - 44/14 as lipid core in ethanol, soya lecithin as emulsifier, and polysorbate 80 as surfactant in the aqueous phase. The SLNs were characterized for various physical properties, including particle size, zeta potential, polydispersity, release profile and entrapment efficiency.Results: The yield of SLNs was in the range 151.0 ± 2.4 to 199.1 ± 2.7 nm. Significant changes were observed in mean particle size (nm), Z - potential (mV) and polydispersity index (PDI) of the SLNs by varying the concentration of cryoprotectant. EVG – SLNs demonstrated a 800 – 1030-fold enhancement in aqueous solubility compared with plain EVG. The dissolution efficiency (DE) for SLNs was > 63 % in all cases and increased up to 83 % with increasing lipid load.Conclusion: Successful preparation and characterization of elvitegravir–loaded solid lipid nanoparticles by solvent injection method has been accomplished in this study.Keywords: Elvitegravir, Solid lipid nanoparticles, Cryoprotectant, Lipid load, Entrapment efficiency

The quantitative characterisation of the solid form of drug substances and drug products is gaining importance due to product quality and performance that is based on stringent regulatory guidelines. Therefore, in this study, thermal, X-ray diffraction and spectroscopic methods were evaluated to obtain a simple, quick and precise method for the quantitative analysis of binary mixtures of eletriptan hydrobromide polymorphs in powder form. The two polymorphs are discernible using differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Quantitative methods using each technique were developed and validated using spiked standards prepared by geometrical mixing of the pure polymorphs. The estimated limit of detection values of the methods using DSC, PXRD and DRIFTS were determined to be 0.24%, 2.01% and 2.06%, respectively. A careful evaluation of the validation results from the three methods indicated that DSC performed better than PXRD and DRIFTS. The DSC method was determined to be the best alternative to PXRD and DRIFTS due to its measurement capability, simplicity, cost effectiveness and quickness. The real-time sample batch analysis was performed, and the advantages and applications of the study are discussed.

The aim of the current exertion was to prepare Solid Dispersion of Etravirine by Spray drying technique to enhance aqueous solubility and dissolution rate. Solid dispersions (SD) of Etravirine were prepared using Copovidone and Povidone-Copovidone in dichloromethane and physical properties were characterized by Scanning electron microscopy (SEM), X-Ray diffractometry (PXRD), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC). SD's were evaluated for equilibrium solubility and in vitro drug release profile by dissolution testing. The diffraction and thermal patterns of solid dispersions indicated the conversion of crystalline Etravirine to amorphous form. The solubility of drug in SD's was appreciably more when evaluated against physical mixtures and intact Etravirine. Drug release characteristics were evaluated in three different media at different pH and found that drug release kinetic was best described by weibull mathematical model. Mean dissolution time (MDT) and Dissolution efficiency (DE %) in different media were evaluated for SDs. Statistical evaluation of dissolution data using Analysis Of Variance (ANOVA) single factor and t-Test: Paired Two Sample for Means was applied for better understanding and evaluation.

Objective: In the present study, simultaneous determination of degree of crystallinity content in abacavir (ABC), lamivudine (3TC) and neverapine (NVP) from there combination drug product using X-ray powder diffraction (XRPD) technique is developed and validated. Methods: The X-ray procedure for the identification and determination of the degree of crystallinity in ABC, 3TC and NVP drug product is developed and validated. It is based on the X-ray diffraction from crystalline region of the drug product. The characteristic peaks of the three drugs were characterized using XRPD. Results: ABC, 3TC and NVP concentrations ranging from 70% to 130% in drug product were prepared and linearity in this concentration range is described. The % coefficient of variation (%CV) was found to be 0.9982 for ABC, 0.9978 for 3TC and 0.9984 for NVP. The mean recoveries were found to be 100.3% for ABC, 99.0% for 3TC and 100.8% for NVP. Regressions statistics and Analysis of variance (ANOVA) table results were evaluated and found to be satisfactory. Conclusions: The method has been applied to unknown mixtures of drug formulations and stability samples. The proposed method can be useful in the quality control of combination drug products. Keywords :CrystallinityDrugproduct,X-ray powder diffraction,Regressions statistics,Analysis of variance.