Abstract: A test/control procedure and material is provided to facilitate standardization of immunostaining techniques and the assessment of their results. Pellets of an absorbent gel such as agar gel are caused to adsorb individual specific concentrations of an antigen of interest. The adsorbed antigens are confined to the individual pellets as by fixation or by enclosure in a diffusion-inhibiting barrier, and the pellets are installed in individual wells in a block of the gel in a manner to become integrated therein. The block may then be subjected to the same preparative routines as a tissue sample, sectioned and mounted like the sample, and then subjected to immunostaining by the same routine as the sample sections to provide a valid basis for assessment of the stained sample sections by comparison with the stained gel block sections. A gel block of suitable configuration is also disclosed.

Abstract: A tissue or like processing method involving application of liquids to carrier-mounted material, e.g. a thin tissue section mounted on a microscope slide (10), is characterized by disposing a channel-defining element (1) adjacent to the carrier (10) to form an assembly providing an enclosure (11) for the material on the carrier. The enclosure (11) has an inlet (13) and an outlet (14) and has capillary dimensions. The assembly is disposed with the inlet (13) above the outlet (14) and liquid introduced into the inlet fills the enclosure and is retained in contact with the material on the carrier by surface tension effect. Further liquid introduced to the inlet (13) displaces the first liquid progressively to the outlet (14). A sequence of liquids can thus be brought successively into contact with the material with minimum wastage, by feeding the liquids successively to the inlet (13) of an assembly.