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.