Silver nanoparticles were successfully synthesized by heating mixed solutions of silver nitrate, hexamethylenetetramine (HMTA), and polyvinylpyrrolidone (PVP) at 80• C for 7 min. The characterization of as-prepared silver nanoparticles were carried out by measuring ultraviolet-visible (UV-vis) and FTIR spectra, and images of transmission electron microscopy (TEM). The results of extinction spectra and TEM images indicated that the higher concentration of PVP and higher MW of PVP decrease the particle size of silver nanoparticles produced in the present systems. In addition, the interaction between silver atoms and oxygen atoms in the carbonyl group of PVP was also discussed by FTIR spectroscopy. It can be concluded that this heating method at 80• C is very useful for the preparation of stable and homogeneous silver nanoparticles in the present systems.

We have synthesized stable gold nanoparticles (AuNPs) by a simple ultrasonic irradiation in water/alcohol binary solutions without additive stabilizer agents. Methanol, ethanol, and 1-propanol are used as solvents. The morphology and optical properties of the sonochemically synthesized AuNPs are characterized using SEM and UVvis spectroscopy. The average particle diameter of as-prepared AuNPs was 36 ± 10 nm for water/methanol system (methanol: 25 vol%), 56 ± 17 nm for water/ethanol system (ethanol:35 vol%), and 24 ± 7 nm for water/1-propanol system (1-propanol: 35 vol%). The water/1-propanol system give the smallest average particle diameter together with the narrowest particle size distribution. This fact also support that the hydrophobicity of 1-propanol is higher, because the side chain of 1-propanol is longer than those in the other alcohols. Thus, it can be concluded that the dispersion of AuNPs is enhanced and their aggregation and growth are suppressed.

The current study was conducted with the aim to evaluate Ivy leaf extract to authenticate the quality of extract. Evaluation was conducted on different physicochemical factors of extract that include physical appearance, organoleptic properties and solubility. Loss on drying, microbial analysis and heavy metal analysis was also carried out to execute the safety of extract. High performance liquid chromatography was executed to evaluate the presence of Hederacoside C in Ivy leaf extract employing phosphoric acid 85 %, acetonitrile, water (2:140:860 v/v/v) as a mobile phase. Extract exhibited greenish brown color, distinctive odor and sweet taste. An Ivy extract was found in agreement of the allowable microbial limit as well as with the heavy metal contents limit. The presence of Hederacoside C in Ivy leaf extract was confirmed by HPLC. The current evaluation reveals conformity with all the analytical procedures. Hence Ivy leaf extract is well standardized formulation at the base line consideration.

We propose a new type of preparation method of silver nanoparticles (AgNps) by using a triazine benzenethiol derivative such as (4,6-dimethoxy-1,3,5-triazin-2-yl)-4-mercaptobenzoate (TBSH) as a reductant in the presence of a cationic surfactant such as cetyltrimethylammonium chloride (CTAC) or cetyltrimethylammonium bromide (CTAB). The formation amount and stability of AgNps in the presence of CTAC is compared with those in CTAB system; the addition of CTAC play important roles for the formation of AgNps. The optical properties of as prepared AgNps were characterized by using UV-vis, FTIR, and X-ray photoelectron (XPS). Transmission electron microscopy (TEM) images of as-prepared AgNps distinctly show the morphology of AgNps with average size of 30 nm. CTAC-concentration dependence of FTIR spectra indicates that the combination of rigid and compact network of TBSH and CTAC capped on AgNps significantly affects the size and shape of AgNps and also exhibit the presence of enhanced gauche conformers below the critical micellar concentration (cmc ∼ 0.6 mM) and trans conformers at cmc and above cmc of CTAC. Based on the present results, we propose a model of molecular structure and stability of AgNps.

No abstract

Levothyroxine is an oral form of drug that is used for hypothyroidism disorder. Hypothyroidism disorder is a condition in which the gland does not produce enough thyroid hormones for the body to perform its functions effectively. In the commercial market, various brands of levothyroxine are available that are frequently prescribed for hypothyroidism. In this study, we determined the comparative assessment of physicochemical properties of different brands of marketed available levothyroxine oral tablets in Karachi, Pakistan. In this study, we evaluated the pharmaceutical equivalency of different marketed brands of levothyroxine by using QC parameters, i.e., weight variation, thickness, hardness, and disintegration. Instruments used for different analyses included digital weighing balance, hardness apparatus, vernier caliper, and disintegration tester. Different brands of levothyroxine were purchased from the different community pharmacies for physicochemical analysis and performed physiochemical tests with the comparison of BP and USP specifications. The physicochemical properties of different marketed brands of levothyroxine were performed through digital weighing balance, hardness apparatus, vernier caliper, and disintegration tester. The weight variation is performed using digital weighing balance. First, we determined the parent drug, i.e., Synthroid .0833; however, the rest of the drugs including Eltroxin, thyroxin, and thyronorm are 0.170, 0.146, and 0.1043. The thickness was measured using vernier caliper, and the calculated values of Synthroid, Eltroxin, thyroxine, and thyronorm were 0.0640, 0.410, 0.0847, and 0.1106. The hardness was measured using hardness tester, and the calculated values for synthroid, Eltroxin, thyroxine, and thyronorm were 3.5400, 3.8300, 3.3700, 3.6800. The disintegration was measured with the disintegration tester, and the calculated values of Synthroid, Eltroxin, thyroxine, and thyronorm were 4 min;10 seconds, 1 min, 2 min; 48 seconds and 1 minutes; 43 seconds. Physicochemical properties of all four brands of levothyroxine showed slight differences within the range of BP and USP. This research compared the physicochemical properties of different marketed available brands of levothyroxine with those of a parent company in Karachi, Pakistan. Drug release investigation and bioequivalence should be performed in the near future for more authenticity and prescription confidence.

The objective of the present study was to determine the acute and subacute toxicity profile of a polyherbal formulation called “Goubion” in addition to the in vivo antihyperuricemic study using fructose-induced hyperuricemia. Goubion is a combination of Colchicum autumnale (tuber), Tribulus terresteris (fruit), Vitex negundo (leaves), Smilax chinensis (root), Glycyrrhiza glabra (root), and Curcuma amada (rhizome). The acute toxicity study revealed no signs of mortality and morbidity at a single dose of 2000 mg/kg. Similarly, the results of the subacute repeated dose toxicity study exhibited no signs of mortality at any of the doses. However, significant changes in hematological, biochemical, and renal parameters were recorded at the dose of 60 mg/kg. Antihyperuricemic activity was tested at the dose of 15 mg/kg and 20 mg/kg of Goubion, respectively against 5 mg/kg Allopurinol. Based on the antihyperuricemic study, we infer that the Goubion has a significant hypouricemic action, as it remarkably decreased the elevated uric acid levels. The results also suggest the potential inhibitory capability of Goubion on xanthine oxidase dehydrogenase might be the mechanism behind the hypouricemic effect.