Assessment of behavioral changes and antitumor effects of silver nanoparticles synthesized using diosgenin in mice model

Lipid-based drug delivery systems, or lipidic carriers, are being extensively employed to enhance the bioavailability of poorly-soluble drugs. They have the ability to incorporate both lipophilic and hydrophilic molecules and protecting them against degradation in vitro and in vivo. There is a number of physical attributes of lipid-based nanocarriers that determine their safety, stability, efficacy, as well as their in vitro and in vivo behaviour. These include average particle size/diameter and the polydispersity index (PDI), which is an indication of their quality with respect to the size distribution. The suitability of nanocarrier formulations for a particular route of drug administration depends on their average diameter, PDI and size stability, among other parameters. Controlling and validating these parameters are of key importance for the effective clinical applications of nanocarrier formulations. This review highlights the significance of size and PDI in the successful design, formulation and development of nanosystems for pharmaceutical, nutraceutical and other applications. Liposomes, nanoliposomes, vesicular phospholipid gels, solid lipid nanoparticles, transfersomes and tocosomes are presented as frequently-used lipidic drug carriers. The advantages and limitations of a range of available analytical techniques used to characterize lipidic nanocarrier formulations are also covered.

A spectrophotometric method has been developed for the quantitative determination of antioxidant capacity. The assay is based on the reduction of Mo(VI) to Mo(V) by the sample analyte and the subsequent formation of a green phosphate/Mo(V) complex at acidic pH. The method has been optimized and characterized with respect to linearity interval, repetitivity and reproducibility, and molar absorption coefficients for the quantitation of several antioxidants, including vitamin E. The phosphomolybdenum method, in combination with hexane monophasic extraction, has also been adapted for the specific determination of vitamin E in seeds. The results obtained with the proposed method were validated by comparison with a standard HPLC method. The phosphomolybdenum method is routinely applied in our laboratory to evaluate the total antioxidant capacity of plant extracts and to determine vitamin E in a variety of grains and seeds, including corn and soybean. Copyright 1999 Academic Press.

The elevated plus maze is a widely used behavioral assay for rodents and it has been validated to assess the anti-anxiety effects of pharmacological agents and steroid hormones, and to define brain regions and mechanisms underlying anxiety-related behavior. Briefly, rats or mice are placed at the junction of the four arms of the maze, facing an open arm, and entries/duration in each arm are recorded by a video-tracking system and observer simultaneously for 5 min. Other ethological parameters (i.e., rears, head dips and stretched-attend postures) can also be observed. An increase in open arm activity (duration and/or entries) reflects anti-anxiety behavior. In our laboratory, rats or mice are exposed to the plus maze on one occasion; thus, results can be obtained in 5 min per rodent.