Abstract: When a diluted poly(vinyl alcohol)(PVA) aqueous solution was slowly dropped into excess 25% glutaraldehyde solution, the obtained product was not the normally formed hydrogels(by gelation method) but plastic white powder with numerous free —CHO groups on the surface. The density of the useful —CHO groups was both calculated in theory(>5.5 mmol/g) and chemically determined(>1.6 mmol/g). The length of the —CHO linkers was prolonged by reacting with the amino compounds and the functional groups correspondingly changed to be —NH₂, —SH, or —NH—NH₂. All the synthesized macromolecular compounds generally have hydrophilic three-dimensional surface, in sufficient quantities and flexible functional groups and low fluorescent background, such synthesized macromolecular compounds are good for fabrication of the bio-microarrays, especially carbohydrate arrays. For example, the powders with groups of both the —CHO and —NH—NH2 were used to immobilize the heparin. Anticoagulant experiments show that the immobilized molecules still played a good biological function.

Key words: Poly(vinyl alcohol)(PVA), Aldehyde spacered powders, 3D-microarray, Heparin, Immobilization chemistry