methods are provided herein for modifying antigenic carbohydrate epitopes within a xenographic bioprosthetic tissue by oxidation of vicinal diols to form aldehydes or acids and subsequence reductive amination of aldehydes to form stable secondary amines , or amidation or esterification of acids to form stable amides or esters . advantageously , methods provided herein mitigate the antigenicity of the bioprosthetic tissue while leaving the overall tissue structure substantially undisturbed , and thereby enhance the durability , safety and performance of the bioprosthetic implant .