2018-12-212018-12-212005-12ZAMPIERI, Ana Lúcia Teixeira de Carvalho; LIMA, Eliana Martins; DINIZ, Danielle Guimarães Almeida. Estudo da ligação cruzada induzida pelo formaldeído em cápsulas de gelatina dura. Revista Eletrônica de Farmácia, Goiânia, v. 2, n. 2, p. 73-79, jul./dez. 2005. Disponível em: <https://www.revistas.ufg.br/REF/article/view/1951/1884>.e- 1808-0804http://repositorio.bc.ufg.br/handle/ri/16631Formaldehyde induced cross-linking in gelatin can be used to promote gastric-resistance in gelatin based oral drug delivery systems. However, thorough evaluations for each drug class must be performed before establishing its use for this purpose. In this work, formaldehyde induced cross-linking in hard gelatin capsules was investigated. Capsules were immersed in hydroalcoholic (70-90%) solutions containing several different concentrations of formaldehyde. Cross-linking was evaluated by the determination of free amino groups in the samples by UV spectrophotometry. Residual formaldehyde was determined by HPLC. Cross-linking reaction was strongly influenced by water and alcohol concentrations in the solutions used for the treatment of the capsules. Residual formaldehyde was within acceptable range. However, repeated analysis during a short term storage of the capsules proved that the cross-linking continues as long as any residual formaldehyde is present, leading to a much higher resistance than what would be convenient for the oral drug delivery.porAcesso AbertoGastro-resistênciaCápsulas de gelatinaFormaldeídoLigação-cruzadaGastric-resistanceGelatin capsulesFormaldehydeCross-linkingArtigo10.5216/ref.v2i2.1951