Immunological slide

Treu (1976) measured transmission spectra (optical density) for indium films of the type used for immunological slides. His calculations based on Mie theory led him to the conclusion that this theory was not compatible with observations. In particular, calculations for spheres of diameter 1390 A showed a feature that was not observed in experiments. Although calculations for spheres half this size did not show this feature, the wavelength of maximum optical density was much shorter than that observed. 

The absorption spectrum of isolated indium spheres differs from that of closely packed oblate spheroids in that the peak shifts from 2230 A to 4100 A about half of this shift is attributable to particle shape and half to particle interaction. Indium particles on immunological slides are not identical, however, but are distributed in size and shape about some mean this tends to broaden the spectrum. 

Our assertion that the darkening of immunological slides, which are observed by transmitted light, is primarily an absorption rather than a scattering phenomenon can be supported by a simple calculation. The cross sections for absorption and scattering by a single, uncoated oblate spheroid illuminated... 

Treu, J. I., 1976. Mie scattering, Maxwell Garnett theory, and the Giaever immunology slide, Appl. Opt., 15, 2746-2750. 

Rinse slides in TBS and apply the primary antibody of the second immunological sequence for 2 h on paraffin sections or for 30 min on frozen sections. 

Automated immunohistochemistry stainers (AIHS) repetitively and reliably dispense and allow for the use of microliter quantities of reagents for individual slide reactions, thus saving expensive immunologic reagents. 

The test strips or slides cannot be calibrated with aqueous solutions (primary calibrator). This is because the matrix of the sample and of the primary calibrator is not the same. Calibration with so-called secondary calibrators is an alternative. The concentration or activity of the intended analyte is determined by chemical, enzymatic, physical or immunological analysis in any case it should be obtained by the best available method. 

For application of immunological reagents drain the slides, and place them on a horizontal staining rack, in a humidified box. 

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