Abstract: A heterobifunctional cross-linking reagent having a carbohydrate backbone (derived from a chitin substrate) is disclosed. The cross-linker is available in a variety of lengths, is highly water-soluble, and can be formulated to undergo cleavage catalyzed by the enzyme lysozyme.

Abstract: A method for amplifying enzyme activity is disclosed. Enzyme amplification is achieved by covalently bonding enzyme to a supporting material via a molecular chain which is a substrate for the enzyme, then introducing a small amount of enzyme in the free state to this system, causing release of a large amount of bound enzyme. In an alternative embodiment, complementary enzymatically inactive fragments of an active enzyme, which fragments can recombine to form active enzyme, are covalently attached to separate support materials by a molecular chain material which is a substrate for the active enzyme, and these two fragment-supported conjugates are connected in series. Upon application of free enzyme or free complementary enzyme to one of these fragment-support conjugates, followed by application of the resulting product mixture to the second fragment-support conjugate, a large amount of free enzyme is ultimately produced.

Abstract: Enzyme amplification is achieved by covalently bonding enzyme to a supporting material via a molecular chain which is a substrate for the enzyme, then introducing a small amount of enzyme in the free state to this system, causing release of a large amount of bound enzyme. In an alternative embodiment, complementary enzymatically inactive fragments of an active enzyme, which fragments can recombine to form active enzyme, are covalently attached to separate support materials by a molecular chain material which is a substrate for the active enzyme, and these two fragment-support conjugates are connected in series. Upon application of free enzyme or free complementary enzyme to one of these fragment-support conjugates, followed by application of the resulting product mixture to the second fragment-support conjugate, a large amount of free enzyme is ultimately produced.

Abstract: A repetitive immunoassay analytical method for determination of a free analyte is carried out by loading an affinity column of covalently bound analyte with tagged antibody, passing a continuous aqueous stream of carrier liquid over the column, introducing an aliquot of a sample to be analyzed for free analyte into the carrier stream upstream of the column, and monitoring the eluting carrier stream for a signal spike resulting from the presence of tagged antibody material released from the column by the application of free analyte in the analytical sample. Many samples may be analyzed by this method before the antibody-loaded affinity column needs to be regenerated. It is also disclosed that substrate-analyte conjugates of superior stability are produced by linking a substrate to a hydroxyalkyl analyte via an amino, hydrazide, or sulfide linking group replacing a hydroxy group.