{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T15:06:57Z","timestamp":1779289617338,"version":"3.51.4"},"reference-count":19,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2020,12,7]],"date-time":"2020-12-07T00:00:00Z","timestamp":1607299200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Minist\u00e8re de l'Enseignement sup\u00e9rieur, de la Recherche et de l'Innovation","award":["2018\/0502"],"award-info":[{"award-number":["2018\/0502"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>In leathers, formaldehyde is currently analyzed according to EN ISO 17226-1 standard, by reversed phase liquid chromatography after off-line precolumn derivatization with 2,4 dinitrophenylhydrazine (DNPH) in strong acidic conditions. We first demonstrate that this standard is not adapted to leather retanned with resins likely to release formaldehyde by hydrolysis. Indeed, formaldehyde content may be largely overestimated due to concomitant resin hydrolysis (in harsh acidic conditions) that releases formaldehyde during the derivatization step and during the waiting time on autosampler before analysis. Therefore, we thoroughly studied the derivatization step in order to propose new derivatization conditions. Replacing orthophosphoric acid by less acidic buffer solutions is not enough to avoid hydrolysis. A derivatization without adding acid is realized by solubilizing DNPH in acetonitrile instead of orthophosphoric acid. These conditions lead to a complete derivatization of formaldehyde in 3 h at 50 \u00b0C (in a water bath) while avoiding the hydrolysis of co-extracted dicyandiamide and melamine resins. The as-obtained leather extracts are stable over time. Formaldehyde contents found with this method agree with the formaldehyde content measured immediately at the end of derivatization reaction in standard conditions or with formaldehyde content measured by a home-designed flow injection analysis with acetylacetone online derivatization and UV detection.<\/jats:p>","DOI":"10.3390\/molecules25235765","type":"journal-article","created":{"date-parts":[[2020,12,10]],"date-time":"2020-12-10T22:15:36Z","timestamp":1607638536000},"page":"5765","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Towards a Non-Biased Formaldehyde Quantification in Leather: New Derivatization Conditions before HPLC Analysis of 2,4-Dinitrophenylhydrazine Derivatives"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2935-0410","authenticated-orcid":false,"given":"Caroline","family":"Bourgeois","sequence":"first","affiliation":[{"name":"CTC, Comit\u00e9 Professionnel de D\u00e9veloppement Economique, Cuir, Chaussure, Maroquinerie, Ganterie, 4 Rue Hermann Frenkel, 69007 Lyon, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nicolas","family":"Blanc","sequence":"additional","affiliation":[{"name":"CTC, Comit\u00e9 Professionnel de D\u00e9veloppement Economique, Cuir, Chaussure, Maroquinerie, Ganterie, 4 Rue Hermann Frenkel, 69007 Lyon, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jean-Claude","family":"Cannot","sequence":"additional","affiliation":[{"name":"CTC, Comit\u00e9 Professionnel de D\u00e9veloppement Economique, Cuir, Chaussure, Maroquinerie, Ganterie, 4 Rue Hermann Frenkel, 69007 Lyon, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8613-7870","authenticated-orcid":false,"given":"Claire","family":"Demesmay","sequence":"additional","affiliation":[{"name":"CNRS, Institut des Sciences Analytiques, Universit\u00e9 Claude Bernard Lyon 1, UMR 5280, 5 Rue de la Doua, 69100 Villeurbanne, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1080\/10590501.2011.629972","article-title":"Exposure to Formaldehyde and Its Potential Human Health Hazards","volume":"29","author":"Kim","year":"2011","journal-title":"J. Environ. Sci. Health Part C"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1111\/cod.13052","article-title":"Ten-year trends in contact allergy to formaldehyde and formaldehyde-releasers","volume":"79","author":"Fasth","year":"2018","journal-title":"Contact Dermat."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Rowell, R.M. (2012). Wood Adhesion and Adhesives. Handbook of Wood Chemistry and Wood Composites, CRC Press. [2nd ed.].","DOI":"10.1201\/b12487"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1111\/j.1478-4408.1994.tb01628.x","article-title":"Formaldehyde in textiles","volume":"110","author":"Hewson","year":"1994","journal-title":"J. Soc. Dyers Colour."},{"key":"ref_5","first-page":"46","article-title":"Formaldehyde in leather: Causes and avoidance","volume":"15","author":"Wolf","year":"2002","journal-title":"World Leather"},{"key":"ref_6","unstructured":"BLC Leather Technology Centre Ltd. (2008). 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Leather Technol. Chem. J."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"310","DOI":"10.1016\/S0021-9673(01)82130-0","article-title":"Effect of pH on the reaction of 2,4-dinitrophenylhydrazine with formaldehyde and acetaldehyde","volume":"455","author":"Bicking","year":"1988","journal-title":"J. Chromatogr. A"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"416","DOI":"10.1042\/bj0550416","article-title":"The colorimetric estimation of formaldehyde by means of the Hantzsch reaction","volume":"55","author":"Nash","year":"1953","journal-title":"Biochem. J."}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/25\/23\/5765\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:42:05Z","timestamp":1760179325000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/25\/23\/5765"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,12,7]]},"references-count":19,"journal-issue":{"issue":"23","published-online":{"date-parts":[[2020,12]]}},"alternative-id":["molecules25235765"],"URL":"https:\/\/doi.org\/10.3390\/molecules25235765","relation":{},"ISSN":["1420-3049"],"issn-type":[{"value":"1420-3049","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,12,7]]}}}