Analysis of human luteinizing hormone and human chorionic gonadotropin preparations of different origins by reversed-phase high-performance liquid chromatography

Specific reversed-phase high-performance liquid chromatography conditions are reported for the analysis of recombinant and native human luteinizing hormone (hLH) and human chorionic gonadotropin (hCG) preparations. Heterodimeric hLH, hCG and their alpha- and beta-subunits migrated with significantly different retention times (t(R)) in the following order of increasing hydrophobicity: alpha-hCG < alpha-hLH < hCG < hLH < beta-hCG < beta-hLH. Under these conditions, the main peak of three hCG preparations ran about 4% faster than the average t(R) (38.35 +/- 0.42 min; RSD = 1.1%) of four hLH preparations. Four heterogeneous urinary products were also analyzed, hLH, hFSH and hCG peaks being identified. Quantitative analysis was validated for the homogeneous preparations and a highly linear dose-response curve (r = 0.99998; p < 0.0001; n = 20) used to assess the accuracy, precision and sensitivity of the analysis. Quantification of the different gonadotropins in the heterogeneous preparations was also carried out, but with limitations in accuracy. (C) 2010 Elsevier B.V. All rights reserved.