Monte Carlo (MC) simulations are often used in calculations of radiation transport to enable accurate prediction of radiation-dose, even though the computation is relatively time-consuming. In a typical MC simulation, significant computation time is allocated to following non-important events. To address this issue, variance reduction techniques (VRTs) have been suggested for reducing the statistical variance for the same computation time. Among the available MC simulation codes, electron gamma shower (National Research Council of Canada) (EGSnrc) is a general-purpose coupled electron-photon transport code that also features an even-handed, rich set of VRTs. The most well-known VRTs are the photon splitting, Russian roulette (RR), and photon cross-section enhancement (XCSE) techniques. The objective of this work was to determine the optimal combination of VRTs that increases the simulation speed and the efficiency of simulation, without compromising its accuracy. Selection of VRTs was performed using EGSnrc MC User codes, such as cavity and egs_chamber, for simulating various ion chamber geometries using 6 MV photon beams and 1.25 MeV 60Co photon beams. The results show that the combination of XCSE and RR yields the highest efficiency for ion-chamber dose calculations inside a 30 cm × 30 cm × 30 cm water phantom. Hence, properly selecting a different VRT without altering the underlying physics increases the efficiency of MC simulations for ion-chamber dose calculation.

The aim of the study was to formulate and investigate the pharmacokinetic parameters for the tablets of herbal extract of caffeine with comparison to synthetic formulation. The tablets of the aqueous herbal extract of leaves of Camellia sinensis and synthetic caffeine were formulated by wet granulation technique. The HPLC and HPTLC were applied as analytical tools for estimation of caffeine. The batches of formulation (B1 to B7) were subjected for various pre and post-formulation studies. The pharmacokinetic of the batch B5 was assessed in rabbits, and the results were compared to synthetic batch B7. With the suitable pre and post-formulation results, the B5 showed in vitro release of 90.54% of caffeine at the end of 60 min. The release followed first order kinetics and the plot of Higuchi and Peppas confirms anomalous diffusion as the basic mechanism behind the release. B5 revealed non-significant mean Cmax, t1/2, and AUC of 1.88 μg/ml, 5.52 h and 9.67 μg.h/ml respectively compared to B7. The study highlights; no significant difference in the pharmacological effect of caffeine when administered in the form of extract. The administration of herbal extract can further provide the other health benefits lacked by synthetic caffeine.

Aim: The current project involves developing an RP-HPLC method for simultaneous quantification of Candesartan Cilexetil and Pioglitazone based on analytical quality by design (AQbD). Materials and methods: When analysed in the Design Expert application, the critical method parameters were systematically refined using Central Composite Design and contours were derived for significant variables. A contour plot has been used to discover the technique operable design region that governs response variation, which is then empirically tested. Results: Successful chromatographic separation of title analytes was achieved on kromasil C18 (150 × 4.6 mm, 5 µm) column at 30 °C with mobile phase comprising 60% 20 Mm Potassium dihydrogen orthophosphate and 40% acetonitrile (v/v), isocratic elution pattern, 0.9 mL/min flow rate, and UV detection at 220 nm. The linear model for Candesartan Cilexetil was from 4 to 24 µg/ mL and Pioglitazone at 7.5–45 µg/ mL, respectively. Conclusion: The method met all the ICH Q2 (R1) validation criteria. The current approach aided for analysing simultaneous drugs can be expanded into quantifying drugs in biological matrix predominance with maximum recovery.

Objective: The focus of this study was to establish a simple, robust, and validated RP-column approach to analyze Candesartan and Pioglitazone in a bilayer tablet dosage form. To broaden patient compliance in conditions such as diabetes and hypertension, a combination of drugs is often prescribed. As a result, a bilayer tablet containing a fixed-dose combination of 8 mg of Candesartan and 15 mg of Pioglitazone was developed. Both drugs were analyzed and chromatographically separated using the liquid chromatography technique. Methodology: waters 2695 with a quaternary pump and Inertsil C18 column mobile phase as buffer: acetonitrile (60:40) and flow rate of 1ml per minute and detection at 220nm was used for performing Chromatography. Results: Internal standard, Candesartan, and Pioglitazone eluted with retention times of 2.208, 2.569, and 3.553 minutes, respectively. There was no interference found between the peaks. With a correlation value of 0.999, the approach is verified across a linear range of 0.5 µg/ml – 20.0µg/ml for Candesartan and 0.08 µg/ml – 3.2 µg/ml for Pioglitazone. 6 samples at LLOQ level were analyzed for accuracy and precision and found to be in limit and all the analytes were stable at 28 °C and  -80 °C in human plasma.