Acknowledgement

The authors would like to extend their sincere appreciation to Oscar Crasson and Jérémy Hermans from IDS for their contribution, including the provision of antibodies 1M0161 and 1M0122 and kits, as well as their assistance in the development of the affinity chromatography method. Additionally, we would like to express our gratitude to the ”Fonds spéciaux à la recherche de la Faculté de Médecine de l’Université de Liège” for their financial support. [1] Szulc, P., Bone turnover: Biology and assessment tools.Best Pract. Res. Clin. Endocrinol. Metab. 2018, 32, 725–738.[2] Lane, N.E., Epidemiology, etiology, and diagnosis of osteoporosis. Am. J. Obstet. Gynecol. 2006, 194.[3] Burge, R., Dawson-Hughes, B., Solomon, D.H., Wong, J.B., et al., Incidence and economic burden of osteoporosis-related fractures in the United States, 2005-2025. J. Bone Miner. 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List of the identified peptides containing a lysine known to be involved in the pyridinoline crosslinks.