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In the present work, pulsed radio frequency (RF) plasma (PRFP) was used to functionalize omeprazole (OME) microparticles using precursor monomers methacrylic acid (MAA) and methyl methacrylate (MMA). This method had two significant factors involved – 1) ratio of monomer flow rate and 2) graded deposition by systematically varying the duty cycle of pulsed plasma. The MAA flow was set to 100 cc/min and MMA to 200 cc/min to rationalize the ratio (1:2) of monomers. Systematic variation in duty cycle (keeping ON time constant and increasing OFF time of the pulse) ensured graded deposition and functionalization of OME. The plasma functionalized OME microparticles were evaluated in-vitro via dissolution studies in pH 1.2 buffer showed a cumulative release of 3.6–9.1% within 120 min compared to complete release under 60 min in pH 6.8. Raman analysis exhibited the absence of peaks from 1800 to 1000 cm−1 and XPS studies showed an increase in oxygen-containing moieties on plasma functionalized OME surface. Thermal, NMR and HR-MS analysis confirmed successful deposition without alteration in original OME molecular structure. The decreased contact angle of post plasma treated OME resulted from hydrophilization of the OME surface. XRD data of plasma treated OME showed an improved degree of crystallinity with an increase in average crystallite size. Post plasma treated OME microparticles size through DLS corroborated well with SEM. Thus, the use of graded PRFP functionalization has proved it's potent to deliver a new, safe, and cheaper alternative to contemporary drug surface modification methods.

The pulsed oxygen plasma treatment (POPT) of the ritonavir (RTV) powder/compacts was investigated as a novel possible physical technique for improving wettability, intrinsic dissolution rate (IDR), and, consequently, solubility of the poorly water-soluble RTV drug. Induction of POPT for 30 min enhanced 5.87-folds apparent solubility and 1.95-folds IDR at 24 h, attributed to RTV's surface hydrophilization. The POPT RTV exhibited zero contact angle compared to RTV suggesting improved wettability (untreated RTV = 74° and 30 min after POPT = 0°). The ATR-FTIR showed a broad peak of –OH group around 3300 cm -1, and XPS showed an increase in surface oxygen concentration from 9 % to 12 % aided through POPT lead to improved wettability of RTV. Moreover, the increased negative zeta potential was observed due to surface hydroxylation on the POPT RTV, resulting in increased surface polarity and RTV's solubility. It was found that there was no substantial thermal or physical alteration after POPT, as evident from DSC, SEM, and XRD studies. This study successfully demonstrated the impact of POPT on improvement in the wettability, solubility, and IDR of hydrophobic drugs RTV.

This paper deals with an experimental investigation through mathematical modeling was carried to study the effect of welding current, feed rate, number of welding passes on tensile and yield strength during welding of IS 2062 E250 grade steel. The correlations between the welding parameters and performance measures like tensile strength, yield strength were established by multiple linear regression models. The correlation coefficients found close to 0.9 signifies the reliability of the selected model. Hence the model can be effectively used for predicting the response within the domain of the welding parameters. Analysis of variance (ANOVA) was used to predict the impact of welding parameters on the response. Experimental observations show that tensile strength & yield strength mostly affected by a higher order of welding current & number of welding passes. Optimum welding parameters are determined using response surface methodology (RSM).

Lipoleiomyomas are benign mesenchymal tumours of smooth muscle and adipose tissue and uncommonly occur in the uterus. Here we report a case of uterine lipoleiomyoma that manifested purely as intravenous component and clinically presented as a large retroperitoneal mass with extension into inferior vena cava and right atrium. The connection of the mass to the corneal end of the uterus was noted only at surgery.