Abstract: Galactosylhydroxylysine is a terminal degradation product of the bone matrix which thus serves as biochemical marker of bone resorption. A method of synthesizing galactosylhydroxylysine is provided. Antibodies against this synthetically prepared galactosylhydroxylysine conjugated to protein carriers were raised to establish methods to measure galactosylhydroxylysine in biological fluids. The antibodies of the invention recognize native galactosylhydroxylysine and are, for example, useful in the measurement of galactosylhydroxylysine as a biochemical marker of bone resorption in biological fluids. Testing of human serum or adolescent urine resulted in dose-dependent increases in signal intensity using the method of the invention.