Formulation and characterisation of nanosuspension of herbal extracts for enhanced antiradical potential

Nanotechnology is a promising technique to increase the bioavailability of herbal medicines. This paper presents the nanosuspension approach for increasing the aqueous solubility and thereby bioactivity of important herbal extracts. Nanosuspensions of the seeds of three plants extract (Silybum marianum, Elettaria cardamomum and Coriandrum sativum) were prepared by using polyvinyl alcohol (1.5% w/v) as a stabiliser. Prepared nanoparticles were characterised by scanning electron microscope. Activity of nanosuspension formulation was assessed by using four in vitro antioxidant assays. S. marianum, E. cardamomum and C. sativum particle size was observed to fall in range of 446.1 ± 112.6, 456.63 ± 339.2 and 432.1 ± 172.8 nm, respectively, most of the particles were having spherical shape and smooth topology. These synthesised nanoparticles were found to be more effective against quenching free radical than their crude extracts and standards [butylated hydroxyl toluene and ascorbic acid]. C. sativum nanosuspension showed most free radical scavenging potential against 2,2-diphenyl-1-picrylhdrazyl (DPPH) and superoxide free radical scavenging assays (IC₅₀ 0.59 ± 0.01 and 0.81 ± 0.11 mg/ml). S. marianum nanosuspension was found to be most effective against DPPH radicals scavenging (IC₅₀ 0.34 ± 0.02 mg/ml). It was concluded that nanosuspension of herbal medicines potentiates the antioxidant potential.     

Solubility Enhancement of Fe in ZnO Nanoparticles Prepared by Co-Precipitation Method

Journal of Superconductivity and Novel Magnetism - Crystalline ZnO offers an excellent host matrix to create a dilute magnetic semiconductor (DMS) owing to its facile Zn-atom substitution with the...     

Group SkSP-R sampling plan for accelerated life tests

This study presents a group skip-lot sampling plan using resampling (SkSP-R) for accelerated life tests. It is assumed that the lifetime of a product follows Weibull distribution with known shape parameter under the use condition, while the scale parameter can be obtained from acceleration factor. The plan parameters are determined through a non-linear optimisation problem for fixed values of producer’s risk and consumer’s risk. The advantages of the proposed plan over the existing one are explained with some practical examples.     

Effect of Surface Finish on the Pitting Corrosion Behavior of Sensitized AISI 304 Austenitic Stainless Steel Alloys in 3.5% NaCl Solutions

The effect of surface condition down to 120 and 1000-grit finish, corresponding to 1.47 and 0.06 microns RMS (Root Mean Square), respectively, on the pitting corrosion behavior of sensitized and mill-annealed AISI (American iron and steel institute) 304 stainless steel was studied in 3.5% NaCl solutions at 23 and 50°C by electrochemical methods. The polarization curves have revealed a clear dependence of pitting corrosion on the surface finish, on the degree of sensitization, as well as on the test temperature. Surface condition has made a significant contribution to pit initiation in that the pitting potential was lowered as the surface roughness increased. The deleterious effect of surface roughness on the pitting potential of the AISI 304 stainless steel alloy in 3.5% NaCl is more pronounced on sensitized samples and becomes more evident with increasing sensitization time and test temperature.     

Nanotechnology based electrical control and navigation system for worm guidance using electric field gradient

Microsystem Technologies - The objective of this research paper is to find the way to guide the worms in an electric field gradient for a specific time period. Research has been done to guide the...     

Effects of IR Laser Shots on the Surface Hardness and Electrical Resistivity of High-Purity Iron

Annealed specimens of 99.99% pure iron were irradiated with 500, 750, 1000, and 1250 Nd:YAG laser shots. The laser fluence and laser intensity at the laser irradiation spot on the target surface were 4.4 × 10³ J/cm² and 4.8 × 10¹¹ W/cm², respectively. Vickers hardness of irradiated specimens was measured at various points separated by 0.5 mm in four different mutually perpendicular directions around the laser irradiation spot. The surface hardness profile for each irradiated specimen shows an increasing trend in surface hardness till a distance of 3.5 mm from the reference point. The average surface hardness (ASH) is found to increase up to 21% and electrical resistivity increases up to 50% as the number of laser shots is increased to 1250. A linear relationship between electrical resistivity and ASH is observed. Moreover, the ASH follows the well-known Hall-Petch relation, indicating that the crystallite boundaries impede the motion of dislocations to a greater extent as the crystallite size gets smaller.