Hydrodynamic cavitation for scalable exfoliation of few-layered graphene nanosheets.

A scalable manufacturing method for the production of biocompatible fewlayered graphene nanosheets is developed using hydrodynamic cavitation. Scalable exfoliation is induced by employing hydrodynamic cavitation and a serum albumin protein. Unlike acoustic cavitation, the primary means of bubble collapse in hydrodynamic cavitation is caused laterally, thereby separating two adjacent flakes through a shear effect. In this process, bovine serum albumin, a known protein, was employed to act as an effective exfoliation agent and provide desired stability by preventing restacking of the graphene layers. This method was used to study the effect of time of graphene exfoliation in a novel hydrodynamic cavitation system. The fabricated products were characterized using Raman spectroscopy, Transmission electron microscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry. The results showed that with increasing the time of exfoliation, the number of graphene layers decreased based on theI2D/IGratio but disorder increased based on theID/IGratio. At 3 h, theI2D/IGratio was at 0.39 and theID/IGratio was 0.25, while at 6 h theI2D/IGratio was 0.35 andID/IGratio was 0.29. The results of the theoretical and computational analysis this research outlines are needed to obtain an effective cavitation model that can be used to potentially improve graphene synthesis and quality. The captured images of bubble propagation in the solution imply that this fluidic phenomenon could assist the graphene exfoliation. To prove this, a simple cavitation model using a needle valve was designed. The needle valve cavitation setup was able to identify that cavitation assists in graphene exfoliation and this was proved using the graphene characterization data. Based on these findings, the simulation models were designed in ANSYS and COMSOL. Specifically, through the ANSYS simulation, we were able to calculate cavitation numbers for specific flow rates and fluid temperatures.

BCS class II drug loaded protein nanoparticles with enhanced oral bioavailability: in vitro evaluation and in vivo pharmacokinetic study in rats.

The aim of the study was to improve the bioavailability of atorvastatin calcium (ATC) by formulating polymeric nanoparticles (NPs) with an easy and cost-effective approach. ATC entrapped gelatin nanoparticles (AEGNPs) were prepared by using a simple one-step desolvation method. The formed NPs were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and differential scanning calorimetry. Morphological study exhibited a homogenous spherical shape of formulated NPs. FTIR studies revealed the chemical compatibility of the drug with gelatin. The improvement in drug delivery kinetics of AEGNPs could be attributed to amorphization along with the reduction in particle size of ATC. The pharmacokinetic study in Sprague-Dawley rats revealed that the Cmax and AUC0-24 of AEGNPs in rats were ∼4-fold and ∼11-fold higher than that of pure ATC suspension. The research presented successfully shows that AEGNPs preparation by one-step desolvation, using minimum excipients is a quick, easy and reproducible method. These results suggest that the ATC encapsulated gelatin NP is a promising approach for the oral delivery of ATC, improving the bioavailability of the drug.

Quality control of residual solvent content in polymeric microparticles.

Organic solvents are the innate part of pharmaceutical industry, playing vital role in the bulk drug substance as well as finished product manufacturing. Even though they are used for various crucial purposes, they still lack therapeutic beneficial effect and can be toxic if present in unacceptable limits in final product. Hence, their concentration must be regulated in the final pharmaceutical formulation. With the major development in the market of polymeric microparticles in past few decades, drug product manufacturers are paying more attention towards the development of new techniques for reducing residual solvent content of microparticles. This article sheds light on the importance of removal of organic volatile impurities from the formulation and its regulatory aspects. It also highlights how residual solvent affects various physicochemical characteristics of polymeric microparticles and suggests certain solutions as per the current state of art for limiting organic solvent content in the final product.

Status of Day Care Laparoscopic Appendectomy in Developing Countries.

The practice of laparoscopic appendectomy as an ambulatory surgery is uncommon even in apex institutes, more so in developing countries, despite proven feasibility. To promote this practice in the developing countries like ours, we attempted to find the safety and cost effectiveness in such institutions which have limited resources. Thirty cases of symptomatic appendicitis were tried for same day discharge after laparoscopic appendectomies. The results were encouraging with 87% patients discharged on the same day and 13% on the next day in the early morning. Among the next day discharged cases, only 03% stayed for medical reasons (nausea, vomiting, and pain) while 10% stayed as their attendants declined to leave (social reasons), even though they were medically eligible for discharge from the hospital. There were no significant postoperative complications except tolerable pain in all patients and mild to moderate nausea/vomiting in 80%. There was no readmission. The mean length of hospital stay was 11.20 hrs. At the time of discharge all patients were highly satisfied. We concluded that routine same day discharge is safe and feasible after appendectomies in developing countries, with social decline as the main hurdle which can be improved by proper communication.

Beneficial effect of supplemental lipoic acid on diabetes-induced pregnancy loss in the mouse.

Uncontrolled diabetes mellitus (DM) is an etiological factor for recurrent pregnancy loss, fetal growth disorders, and major congenital malformations in the offspring. Antioxidant therapy has been advocated to overcome the oxidant-antioxidant disequilibrium inherent in diabetes. The objective of this article was to evaluate the beneficial effects of alpha-lipoic acid (LA) on fetal outcome in a mouse model of streptozotocin (STZ)-induced DM. Timed pregnant mice were made diabetic by intraperitoneal (IP) injection of a single dose of STZ (200 mg/kg) on gestation day (GD) 2. Diabetic animals were supplemented daily with an IP injection of 15 mg/kg of LA starting on GD 4 and continued through GD 12. Fetuses were examined on GD 18 for malformations and growth restriction. Some diabetic mice injected with Evans blue were examined on GD 3.5 and GD 6.5 to evaluate frequency of implantations. STZ-treated mice had all cardinal signs of DM. LA treatment did not normalize blood glucose levels of DM mice. Rates of pregnancy in saline control, DM, and DM + LA groups were 90%, 28%, and 64%, respectively, indicating that LA promotes pregnancy in DM animals. However, postimplantation resorption showed a threefold increase in the DM + LA group. Rates of intrauterine growth restriction and major congenital malformations were also augmented thus indicating that the interaction between DM and LA has deleterious effects on postimplantation embryos.