Abstract: A reagent for the determination of an antibody against an esterase from pathogenic streptococci, which comprisesreagent 1: an esterase (a) from pathogenic streptococci,reagent 2: a protein (b) which is capable of binding to an antibody (d) against the esterase (a) and is bound to an insoluble carrier, andreagent 3: a reagent (c) for measuring an activity of the esterase (a),and a method for the determination of an antibody against an esterase from pathogenic streptococci. The reagent and method of the present invention are useful for diagnosis of various diseases caused by pathogenic streptococcal infections.

Abstract: .delta.-substituted derivatives of valproic acid are provided for conjugation to antigenic compositions, particularly proteins and enzymes.The antigenic conjugates are employed for the production of antibodies, which find particular use in immunoassays for the determination of valproate.Also are disclosed a kit containing at least the conjugate and the antibody and determination method of valproate using the kit.

Abstract: An insolubilized antibody suitable for an enzyme immuno assay or radio immuno assay, which has characteristic infrared absorptions at around 1,040 cm.sup.-1, 1,540 cm.sup.-1 and 1,640 cm.sup.-1 and is prepared by chemically binding an antibody to cell wall debris of bacteria or yeasts whose shape is globular or rod-like. There is further disclosed an enzyme immuno assay or radio immuno assay using the insolubilized antibody and a kit containing the insolubilized antibody.

Abstract: A reagent for determining lipase activity, which comprises as the active ingredient one of the S-acyl compounds of the formula: ##EQU1## WHEREIN N IS AN INTEGER OF 2 TO 4, INCLUSIVE; N' IS AN INTEGER OF 2 TO 4, INCLUSIVE OR OF 9 TO 13, INCLUSIVE; M IS AN INTEGER OF 3, 7 OR 11; M' IS AN INTEGER OF 4 OR 12; Y IS AN INTEGER OF 1 OR 2; X is sulfur atom or oxygen atom; Y is sulfur atom, oxygen atom or ethylene group; provided that when y is 1, m' is 4 and when y is 2, m' is 12, and a method for determining lipase activity by reacting the S-acyl compound with lipase in a buffer solution containing a chromogenic sulfhydryl reagent and then subjecting the resultant to a colorimetry.