A self-microemulsifying drug delivery system (SMEDDS) has been developed to enhance diffusion rate and oral bioavailability of valsartan. The solubility of valsartan was checked in different oils, surfactants, and cosurfactants and ternary phase diagrams were constructed to evaluate the microemulsion domain. The valsartan SMEDDS was prepared using Capmul MCM (oil), Tween 80 (surfactant), and polyethylene glycol 400 (cosurfactant). The particle size distribution, zeta potential, and polydispersity index were determined and were found to be 12.3 nm, -0.746, and 0.138, respectively. Diffusion rate of valsartan was measured by in vitro dialysis bag method using phosphate buffer pH 6.8 as diffusion media. Developed high-performance liquid chromatography method was used to determine drug content in diffusion media. Oral bioavailability of valsartan SMEDDS was checked by using rabbit model. Results of diffusion rate and oral bioavailability of valsartan SMEDDS were compared with those of pure drug solution and of marketed formulation. Diffusion of valsartan SMEDDS showed maximum drug release when compared to pure drug solution and marketed formulation. The area under curve and time showed significant improvement as the values obtained were 607 ng h/mL and 1 h for SMEDDS in comparison to 445.36 and 1.36 h for market formulation suggesting significant increase (p < 0.01) in oral bioavailability of valsartan SMEDDS.

The study was designed to investigate the effect of cyclodextrins (CDs) on the solubility, dissolution rate, and bioavailability of cilostazol by forming inclusion complexes. Natural CDs like beta-CD, gamma-CD, and the hydrophilic beta-CD derivatives, DM-beta-CD and HP-beta-CD, were used to prepare inclusion complexes with cilostazol. Phase solubility study was carried out and the stability constants were calculated assuming a 1:1 stoichiometry. Solid cilostazol complexes were prepared by coprecipitation and kneading methods and compared with physical mixtures of cilostazol and cyclodextrins. Prepared inclusion complexes were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD) studies. In vitro dissolution study was performed using phosphate buffer pH 6.4, distilled water, and HCl buffer pH 1.2 as dissolution medium. The optimized inclusion complex was studied for its bioavailability in rabbit and the results were compared with those of pure cilostazol and Pletoz-50. Phase solubility study showed dramatic improvement in the solubility of drug by formation of complexes, which was further increased by pH adjustment. The dissolution rate of cilostazol was markedly augmented by the complexation with DM-beta-CD. DSC and XRD curves showed sharp endothermic peaks indicating the reduction in the microcrystallinity of cilostazol. Selected inclusion complex was also stable at ambient temperature up to 6 months. The in vivo study revealed that DM-beta-CD increased the bioavailability of cilostazol with low variability in the absorption. Among all cilostazol-cyclodextrins complexes, cilostazol-DM-beta-CD inclusion complex (1:3) prepared by coprecipitation method showed 1.53-fold and 4.11-fold increase in absorption along with 2.1-fold and 2.97-fold increase in dissolution rate in comparison with Pletoz-50 and pure cilostazol, respectively.

In this work a numerical method, based on the use of spectrophotometric data coupled to Partial least squares (PLS),Principal component regression (PCR) andclassical least square (CLS) multivariate calibration, is evaluated for the simultaneous determination of rifampicin and piperine in bulk and capsule dosage form. Spectra of RIFA and PIPE were recorded at concentrations within their linear ranges 20-50 µg/ml & 1.0 -2.5 µg/ml, respectively and were used to compute a total of 25 synthetic mixtures involving 16 calibration and 9 validation sets between wavelength range of 200 and 500 nm with the wavelengths intervals λ=5 nm in methanol. The suitability of the models was decided on the basis of root mean square error (RMSE) values of calibration and validation data. The analytical performances of these chemometric methods were characterized by relative prediction errors and recovery studies (%) and were compared with each other. These three methods were successfully applied to pharmaceutical formulation (capsule) with no interference with excipients as indicated by the recovery study results. The proposed methods are simple, rapid and can be easily used as an alternative analysis tool in the quality control of drugs and formulation.

Objective: Flavones occupy a special place in the realm of natural and synthetic organic chemistry owing to their diversified biological activities. In this study, a series of chalcone derivatives were synthesized and after cyclization of chalcone to synthesized various substituted flavone derivatives (2A-2L). Methods:The reaction of 2-hydroxy acetophenone with substituted aromatic aldehydes produced chalcone by trituration (NaOH) and conventional methods (KOH/EtOH), which upon further cyclization with dimethyl sulfoxide/I 2 resulted to form flavone derivatives. Results:The purity of compounds was ascertained by melting point and thin-layer chromatography. The synthesized compounds have been characterized by mass, infrared, and 1 H nuclear magnetic resonance spectral analysis. Conclusion:Based on spectral data, it was proved that all synthesized chalcones and flavones derivatives meet the standard values of various spectral techniques and further it will be evaluated for pharmacological activities.

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Background Jatyadi Taila (JT) is a well-known Ayurvedic wound healing product, comprising 16 different medicinally important plants including; Curcuma longa, Terminalia chebula, and Jasminum officinale. Objective The proposed work discusses the development and validation of the green and economic stability-indicating HPTLC method for quantification of the key marker phytoconstituents; curcumin (CUR), gallic acid (GA), and ursolic acid (UA) from Jatyadi Taila (JT). Method Quality standard parameters for JT were determined following standard procedures. The marker constituents CUR, GA, and UA were resolved from JT using toluene: ethyl acetate: formic acid (6: 2: 1, %v/v/v) as mobile phase and subsequently derivatized to estimate UA. The developed plates were subjected to HPTLC-MS analysis. All constituents were subjected to forced degradation to determine the proposed technique's stability-indicating property and the accelerated stability studies of marketed formulation and marker constituents. Greenness evaluation of the method was aided by the AGREE methodology. Results The Rf values of CUR, GA, and UA were found to be 0.60 and 0.60; 0.27 and 0.28; and 0.74 and 0.77 from reference standard and oil samples respectively, when analyzed at 366 nm, 290 nm, and 366 nm respectively. HPTLC-MS was carried out to verify the active constituents present in JT. The constituents followed first-order degradation kinetics. The quantity of CUR, GA, and UA in JT was reduced at the end of accelerated stability studies. The developed approach was validated in compliance with the ICH Q2 (R2) guideline. Conclusion Amongst the chosen key markers, GA was highly unstable during forced degradation. JT should be stored at a controlled temperature using more protective packaging material to ensure its quality and efficacy. Highlights The developed method can be used as a quality control tool for JT as it can be used to determine the stability of the key marker compounds the herbal formulation.

Cilostazol is a promising drug for antiplatelet combination therapy that is very important for treatment for various cardiovascular disorders. However, oral delivery of this drug is greatly impeded by the poor solubility in aqueous solutions. The aim of this study was to develop microemulsion (ME) delivery system capable of improving the drug bioavailability. In this study, Capmul MCM C8 (glycerol monocaprylate) based MEs containing Tween 20(polysorbate 20) and/or Labrafil M 1944(poly oxyglycerides) as surfactant(S) and Transcutol P(diethyl glycol monoethyl ether) as cosurfactant(CoS) were studied as potential delivery systems of cilostazol. A number of such systems were prepared containing different S:CoS ratios(1:1, 2:1 and 3:1) based on phase diagrams. Loading of cilostazol was selected as per solubilization capacity and was characterized for pH, viscosity, conductivity, particle size, zeta potential and % transmittance. The MEs systems were further investigated for chemical stability, diffusion and bioavailability. Cilostazol displayed high solubility in microemulsions with particle size up to 70 nm. It was also stable at ambient temperature up to 6 months without significant change in particle size, zeta potential, and % transmittance. Dilution up to 100 fold with aqueous medium observed a visible cloudiness having a particle size up to 104 nm. The in vitro release, and ex vivo intraduodenal diffusion, and in vivo study indicated the capacity of developed ME to improve the bioavailability (1.43 fold) via oral route administration when compared with commercially available tablets (Pletoz-50).

Stress study was performed on RIFA and PIPE and it was found that these degraded sufficiently in all applied chemical and physical conditions. Thus, the developed RP-HPLC method was found to be suitable for the determination of both the drugs in bulk as well as stability samples of capsule containing various excipients.