There are various methods for the analysis of Potassium Sorbate and Sodium Benzoate in food products, but a rapid and reliable method for identification of these preservatives in Doogh (an Iranian traditional dairy drink) is a procedure, in which high performance liquid chromatography (HPLC) utilized and followed by UV diode array detection of the two preservatives. The aim of this case study w...

The color of human skin of 241 whites, blacks, and orientals was measured by reflection spectrophotometry. Among these groups, major differences in luminous reflectance and excitation purity, but not in dominant wavelength, were observed. The twin absorption bands of oxyhemoglobin at 540 and 580 nm were more prominent in whites (particularly females) than in orientals or blacks. Parameters dete...

Infrared spectrophotometry is rapidly assuming an important place in the biological sciences. Its value derives from the fact that each organic compound has a characteristic and distinct infrared spectrum that can be used to identify it (Randall et al., 1949). The biologist working with cells or tissues is confronted by a highly complex mixture of substances. The infrared spectrum of a cell, th...

Absorption spectrophotometry, a standard tool for quantitative analysis, suffers from two major drawbacks: lack of sensitivity and vulnerability to scattering. It has been pointed out earlier that the solution to these problems lies in using a reflecting cavity as a sample holder. Due to multiple reflections at the cavity wall, the effective pathlength becomes considerably larger than the diame...

Absorption spectrophotometry is the measurement of an interaction between electromagnetic radiation and the molecules, or atoms, of a chemical substance. Techniques frequently employed in pharmaceutical analysis include UV, visible, IR, and atomic absorption spectroscopy. Spectrophotometric measurement in the visible region was formerly referred to as colorimetry; however, it is more precise to...

In this study, zero-, first-, secondand third-order derivative spectrophotometric methods were developed for quantitave determination of atenolol in pharmaceutical preparation. In zero order spectrophotometry, absorbance values were measured at 276 nm in zero order spectra of solution of atenolol in methanol in the range of 245-310 nm. In first derivative spectrophotometry, absorbance values we...

We describe procedures for direct determination of lead and cadmium in blood and urine by flameless atomic absorption spectrophotometry. Before analysis, the samples are pre-ashed in microboats in an ordinary laboratory oven. In this way, many samples can be prepared and pre-ashed simultaneously. We find the procedures presented in this work to be rapid, accurate, and precise.