The hexadecapeptide corresponding to sequence 130-145 of the β-subunit of human chorionic gonadotropin (hCG) according to the amino acid sequence proposed by Morgan et al. was synthesized by successive azide condensation of 4 peptide fragments, followed by TFA treatment and catalytic hydrogenation. This peptide was conjugated with bovine serum albumin (BSA). Antiserum produced against this conjugate did not bind with ¹²⁵I-hCG.