Synthesis, characterization, toxicity and morphology assessments of newly prepared microemulsion systems for delivery of valproic acid

A tetrazolium salt has been used to develop a quantitative colorimetric assay for mammalian cell survival and proliferation. The assay detects living, but not dead cells and the signal generated is dependent on the degree of activation of the cells. This method can therefore be used to measure cytotoxicity, proliferation or activation. The results can be read on a multiwell scanning spectrophotometer (ELISA reader) and show a high degree of precision. No washing steps are used in the assay. The main advantages of the colorimetric assay are its rapidity and precision, and the lack of any radioisotope. We have used the assay to measure proliferative lymphokines, mitogen stimulations and complement-mediated lysis.

This assay for superoxide dismutase (SOD, EC 1.15.1.1) activity involves inhibition of nitroblue tetrazolium reduction, with xanthine-xanthine oxidase used as a superoxide generator. By using a reaction terminator, we can determine 40 samples within 55 min. One unit of activity of pure bovine liver Cu,ZnSOD and chicken liver MnSOD was expressed by 30 ng and 500 ng of protein, respectively. The mean concentrations of Cu,ZnSOD as measured by this method in blood from normal adults were 242 (SEM 4) mg/L in erythrocytes, 548 (SEM 20) micrograms/L in serum, and 173 (SEM 11) micrograms/L in plasma. The Cu,ZnSOD concentrations in serum and plasma of patients with cancer of the large intestine tended to be less and greater than these values, respectively, but not statistically significantly so.