Abstract: The invention concerns a device for the automatic reading of an identification code carried by tubular containers (T) arranged in racks, comprising rotating means (M) acting by friction on the tube (T) cylindrical wall through an orifice (OF) provided in one of the two vertical walls (FL.sub.1, FL.sub.2) which extend longitudinally relative to the displacement axis of the racks (R) to cause the tube to rotate during the code reading phase. The invention is useful for identifying sample tubes when they are introduced into a blood analyzer.

Abstract: The present invention relates to a method of binding an immunological material, selected from antigens and antibodies, to submicron latex particles by covalency or adsorption, in which method, which comprises the stabilization of the latex,(A) (1) acrylic latex particles based on polybutyl methacrylate, whose mean diameter is less than or equal to 100 nm, said latex containing a molar quantity of butyl methacrylate units greater than 50%, having a density of 0.9 to 1.4 g/cm.sup.3 and containing from 100 to 450 microequivalents of COOH groups per gram of latex,are brought into contact, in an appropriate liquid medium having an ionic strength in the range from 0.01 to 0.5 at a pH of 4 to 10, at a temperature of 0.degree. to 60.degree. C.