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Whether a commercially available scanner might be used as a vertical photometer of 96-well microplates for enzyme immunoassay (EIA) was studied. The analytical characteristics of the scanner in this regard were assessed, by comparing the findings with the respective photometric data obtained by a "VICTOR" EIA analyzer. It is concluded that the scanner registration system in combination with "Expert-Lab EIA" may be used in all types of EIA. The scanner system provides additional possibilities as compared with the conventional photometric analyzers.

Described in the paper is a micromethod for the determination of the activity of proteinases in blood serum by an ELISA-based reader. BAPNA was used as substrate for proteolytic enzymes. The method is simple, easily reproducible and cost effective--it fits for large-scale examinations.

Methods for staining of ultramicroenzymelectrophoregrams are described. Sharp and well reproducible bands of isozymes of LDH, MDH, G-6-PD, AcP, AlP, alpha-NAE were obtained from homogenates of cultivated human fibroblasts, of rat's liver, kidney and brain, of human embryonic liver, and in blood serum of man and frog. An extract from the rat brain containing only 3.4 ng of proteins or a quantity of 70-80 fibroblasts were sufficient for obtaining a well differentiated spectrum of LDH isozymes. The ultramicromethod significantly lowers the need in deficit reagents, reduces the cost and time of analysis.

A microfluorimetric method for the determination of the quality of FITC-labeled antisera with the determination of the titer and the optimal working dilution in the FA test is described. Besides, the method permits to determine the confidence factor for any dilution of FITC-antiserum and to compare different lots.

A micromethod, developed for estimation of total lipids in lymphocytes, other blood cells and body tissues, involved extraction of lymphocyte suspension with chloroform-methanol mixture, elimination of non-lipid impurities by means of the extract washing, concentration of the lipid fraction and hydrolysis of dry pellet in minimal volume of concentrated H2SO4. After reaction of the hydrolyzate with phosphorus-vanilin reagent the colour intensity of the reaction products was measured. The procedure described was sensitive and enabled to estimate lipids in minimal volume of biological material; in the lymphocyte fraction isolated from 2 ml of peripheric blood total lipids were measured with accuracy of 1-2 mg.

In microanalysis of mineralized tissues an x-ray spectral method possessed an absolute limit of sensitivity about 5-10 minus 15 g. A relative limit of the method sensitivity constituted hundredth parts of a per cent and locality of the analysis--several cubic microns. The x-ray spectral microanalysis permitted to carry out qualitative and quantitative estimations of content of elements in different structures of biological tissues. The data were obtained on content of calcium and phosphorus in compact part of human tubular bone.

Z. pellucide from oocytes and zygotes of CBA mice and albino rats were lysed in a microvolume of 1% buffered sodium dodecylsulphate (SDS). The microlysate (about 1,0--2,0-10(-7) g protein) was fractionated by means microdiscelectrophoretic technique, using 10%- and 15%-polyacrylamide gel containing 0.1% SDS. The new proteins with increased anodic mobility was found among zonal proteins after fertilization in CBA mice and rats. Homogenous fraction of glycoprotein (approximately molecular weight 44 000) is found in z. pellucida of rat oocytes. This glycoprotein fraction from rat zygote coats produces 3 components moving to anode under electrophoresis. The data obtained support the hypothesis that the mechanism of "zonal fraction" under fertilization in mammals can be due to partial lysis of coat proteins by proteinase of cortical granules.

The dynamics of changes in the spectrum of lactate dehydrogenase was studied in the early pre- and postimplantation development in the CBA mice by the method of ultramicrophoresis. In the preimplantation embryos only LDH-1 was found during the first 5 days of development. The LDH-5 first appears by the 5th day of development and is preserved at all subsequent stages. The LDH spectrum of 5--7 days old embryos is represented by LDH-1 and LDH-5 and a very small amount of hybrid forms. The distribution of isozymes in the spectrum does not correspond to the binomial one. The LDH-1 is completely absent from 8--11 days old embryos and reappears in some tissues beginning from the 13th day of development. The distribution of isozymes in the LDH spectra from the 8th day of development is close to the binomial one.

A modification is described for the method of ultramicroelectrophoretic fractioning of proteins in polyacrylamide gel in capillaries 400--100 microns in diameter. The original construction of the assembly of apparatuses is offered which can be assembled from details made in the USSR. The operation of dosed filling of capillaries is significantly facilitated. The optimal quantity of protein in one sample reaches 1.5--0.1 mkg (depending on the capillary diameter). The reproducability and sharpness of protein fractions by the offered method are not worse compared with the generally accepted method of macro-disc electrophoresis.

Using microspectrometric technique, integral extinction and extinction spectra of crystalline inclusions of two amoeba strains, C and Ct, have been studied. The analysis of extinction spectrum form allowed to suggest that the crystals seen in both amoeba strains have identical chemical composition, whereas the morphological differences between cells in their transparency may be due to different mode of the crystal package. The relative amount of the crystals was measured in both amoeba strains on the basis of the integral extinction value. The distinct differences between the strains were detected in the integral extinction value and in the extinction spectra, which allowed us to use these parameters as genetic markers in the experiments on the nuclear transplantation in amoeba.

A simple method is suggested for fractionation of acid proteins. The method sensitivity is 10(-11) g per single band. Since the available modifications of capillary microelectrophoresis are very complicated to apply to an analysis of protein picograms, such a method was badly needed. Fractionation of the samples is made on polyacrylamide gel tubes up to 40 microns in diameter. An original buffer system is employed. The possibility of fractionating acid proteins from vertebrate animal brain has been demonstrated.