Biomedical subjects

A M Dave

Publications and source records attributed to A M Dave.

4 recordsLinked to original sources

PubMed2002

An assessment of solubility profiles of structurally similar hazardous pesticide in water + methanol mixture and co-solvent effect on partition coefficient.

This paper reports solubility and partition coefficient data for the structurally similar pesticides, fenvalerate and cypermethrin, measured by UV spectrophotometry in binary mixtures of methanol and water at different temperatures. The solubility of both pesticides is much higher in methanol than in water at all temperatures. Partition coefficients were also measured between water+heptanol immiscible mixtures at 298.15K, and these data show a decrease with increasing composition of methanol in water.

Insecticides↗

PubMed2002

Stimulus-responsive "smart" hydrogels as novel drug delivery systems.

Recently, there has been a great deal of research activity in the development of stimulus-responsive polymeric hydrogels. These hydrogels are responsive to external or internal stimuli and the response can be observed through abrupt changes in the physical nature of the network. This property can be favorable in many drug delivery applications. The external stimuli can be temperature, pH, ionic strength, ultrasonic sound, electric current, etc. A majority of the literature related to the development of stimulus-responsive drug delivery systems deals with temperature-sensitive poly(N-isopropyl acrylamide) (pNIPAAm) and its various derivatives. However, acrylic-based pH-sensitive systems with weakly acidic/basic functional groups have also been widely studied. Quite recently, glucose-sensitive hydrogels that are responsive to glucose concentration have been developed to monitor the release of insulin. The present article provides a brief introduction and recent developments in the area of stimulus-responsive hydrogels, particularly those that respond to temperature and pH, and their applications in drug delivery.

Acrylic Resins↗

PubMed2000

Solubility study of hazardous pesticide (chlorpyrifos) by gas chromatography.

Solubility data of a hazardous pesticide like chlorpyrifos are important in order to determine its residual toxicity from soil and to understand its controlled release characteristics. In this paper, solubility of chlorpyrifos was measured by using gas chromatography in pure water, methanol, and water-methanol mixtures at 298.15, 303. 15, and 308.15K. The results indicate that chlorpyrifos is more soluble in methanol than in water. The solubility of chlorpyrifos in water can be enhanced by adding methanol to water. The effect of temperature on the solubility of chlorpyrifos was observed at higher methanol content in the mixture.

Chlorpyrifos↗

PubMed2000

Glutaraldehyde crosslinked sodium alginate beads containing liquid pesticide for soil application.

This paper presents experimental results on the successful encapsulation of a natural liquid pesticide 'neem (Azadirachta Indica A. Juss.) seed oil' hereafter designated as NSO, using sodium alginate (Na-Alg) as a controlled release (CR) polymer after crosslinking with glutaraldehyde (GA). The NSO-containing beads have been prepared by changing the experimental variables such as the extent of crosslinking and the amount of loading in order to optimize the process variables. The absence of chemical interactions between active ingredients and polymer as well as crosslinking agent was confirmed by FTIR spectral measurements. The SEM data indicated that the structure of the walls of the beads are smooth and nonporous. The swelling results indicated that swelling of the polymeric beads decreases with increasing exposure time to the crosslinking agent. However, no significant variation in swelling was observed with different amounts of NSO loading. In order to understand the crosslinkability and its effect on the NSO release patterns of the beads, an attempt was made to calculate the molar mass between crosslinks using the Flory-Rehner equation. The release data have been fitted to an empirical equation to estimate the kinetic parameters.

Alginates↗