Microassay

Hatakeyama, T., Kohzake, H., and Yamasaki, N. (1992) A microassay for proteases using succinylcasein as a substrate. Anal. Biochem. 204, 181-184. 

Donateo, M.T., Gomez-Lechon, M.J., and Castell, J.V. 1993. A microassay for measuring cytochrome P450IA1 and P450IIB1 activities in intact human and rat hepatocytes cultured on 96-well plates. Anal. Biochem. 213 29. 

The other area is the use of microassays in toxicogenomic screening, early detection of the potential for compounds to alter gene expressions with adverse consequences (Pennie, 2000 Nuwaysir et al., 1999). 

Pennie, W.D. (2000). Use of cDNA microassays to probe and understand the toxicological consequences of altered gene expression. Toxicol. Lett. 112-113 473 177. 

Ahmed N, Hale K. 1994. A microassay for urinary phenol using capillary gas chromatography and optimised enzymic hydrolysis. Clin Chim Acta 230 201-208. 

Pick, E. and Mizel, D. (1981) Rapid microassays for the measurement of superoxide and hydrogen peroxide production by macrophages in culture using an automatic enzyme immunoassay reader. J. Immunol. Methods 46, 211-226. 

In an attempt to model such interactions, cDNA microassays have been developed. Microassay technologies are particularly suited for use with human tissues, including brain tissue, because the widest availability of... 

Brumback [28] has described a custom robotic system designed to automate the extraction of proteins from plant samples. Leaf or callus material (5—25 mg) is presented to the robot in microcentrifuge tubes, the system performs buffer dispensing, grinding, centrifugation, and pipetting unit operations, and a cleared supernatant is delivered in a 96-well microassay plate format for subsequent analysis. 

Table 1.4. Diiution protocoi of the microassay (0-40 pg Folin method)...

Umeda, M., Noda, K. Tanaka, K. (1985) Assays for inhibition of metabohc cooperation by a microassay method. In Ashby, J., de Senes, F.J., Draper, M., Ishidate, M., Jr, Margolin, B.H., Matter, B.E. Shelby, M.D., eds. Progress in Mutation Research, Volume 5, Evaluation of Short-Term Tests for Carcinogens. Report of the International Programme on Chemical Safety s Collaborative Study on in vitro assays, Amsterdam, Elsevier Science, pp. 619-622... 

Weinshilboum RM, Raymond FA, Pazmino PA. Human erythrocyte thiopurine methyltransferase radiochemical microassay and biochemical properties. Clin ChimActa 1978 85 323-333. 

The inflammatory reaction around eye bums has been subject of older research and might be more elucidated by means of modem technologies of microassays on molecular and proteinic levels. 

Umeda, M., Noda, K. Tanaka, K. (1985) Assays for inhibition of metabolic cooperation by a microassay method. Prog. Mutat. Res., 5, 619-622... 

Planter, J.J. 1991. A microassay for proteolytic activity. Anal. Biochem. 195 129-131. 

Blais, B. and Vailhen, C. (1995). A novel enzymatic microassay for the determination of lactose in grated parmesan cheese. Food Control 6, 215-217. 

Ostgaard, K. (1992). Enzymic microassay for the determination and characterization of alginates. Carbohydr. Polym. 19 51-59. 

Strand LJ, Swanson AL, Manning J et al. (1972) Radiochemical microassay of delta-aminolevulinic acid synthase in hepatic and erythroid tissue. Anal Biochem 47 457 170... 

Green, F., 3rd, Clausen, C. A., and Highley, T. L., Adaptation of the Nelson-Somogyi reducing-sugar assay to a microassay using microtiter plates. Anal Biochem 1989, 182 (2), 197-9. 

Small quantities of compounds in natural extracts are often a problem when these need to be evaluated in bioassays. Sometimes there is just not enough of the compound isolated to carry out the usual bioassay.20 Microassays have been developed10 1 to overcome this problem. Typically, a microassay is carried out on a thin-layer chromatography plate with a cellulose layer. A small droplet (1.5 pi) of the tested compound in a solvent (1-102 nmol cm-2) is then added on the plate. After the solvent has evaporated a small amount (5 pi) of sucrose solution lmoll-1 is added to the place where the compound was added. In the control the same procedure was followed on a different plate, but with the solvent alone, with no compound added. These two plates are then placed in a petri dish with the test insect species. In the past, when paper chromatography was widely used, a crude plant extract was placed on the origin of the paper and then eluted into bands. The paper was freed of solvent, sprayed with sugar solution, and used directly in a bioassay to see which parts of the paper were not eaten, and therefore of interest for further examination. 

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