Investigation and characterization by TG/DTG-DTA and DSC of the fusion of Riboflavin, and its interaction with the antibiotic norfloxacin in the screening of cocrystal

Autor(es)

Ferreira, Laura Teofilo ^[1] ; Alarcon, Rafael Turra ^[1] ; Perpetuo, Glauco Lini ^[2] ; Bannach, Gilbert ^[1]

Afiliação do(s) autor(es)

^[1] UNESP Sao Paulo State Univ, Dept Chem, Sch Sci, Bauru, SP - Brazil

^[2] UNESP Sao Paulo State Univ, Engn Coll Bauru, Bauru, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY; v. 136, n. 2, p. 581-588, APR 2019.
• Citações Web of Science: 0

Resumo

This work synthesized and characterized the NOR-RIB 1:1 (mol-mol) cocrystal. During a study of the reagents, Riboflavin (RIB) melted at 304 degrees C, which is different from the temperature previously reported in the literature (280-290 degrees C); therefore, this compound was characterized individually. Subsequently, the cocrystal was synthesized with the active pharmaceutical ingredient (API) norfloxacin (NOR) with the RIB coformer, and the mechanochemical synthesis route was adopted. NOR, RIB, and the cocrystal were characterized by thermogravimetry-differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), DSC coupled to a microscope (photo-DSC), mid-infrared spectroscopy (MIR), and powder X-ray diffraction. The results of thermal analysis showed that the RIB starts decomposition process (260 degrees C) and then melts (304 degrees C). The MIR found that beginning at 295 degrees C, the RIB passes into the form of a decomposition intermediate; therefore, the melting point observed in the DSC curve is related to this decomposition material. The cocrystal presented thermal stability (200 degrees C) lower than the API (235 degrees C) and the coformer (260 degrees C). The DSC curve did not contain a melting peak. The bands at 1726 cm(-1) (C=O of the carboxylic acid) for the NOR, and the band at 3326 cm(-1) (stretch O-H), among others, were not visible for the cocrystal in the MIR spectrum, indicating interactions in these regions. The X-ray diffractograms showed a new diffraction pattern, which proved the obtainment of a new phase and cocrystal formation. (AU)

• Processo FAPESP: 13/09022-7 - Estudos termoanalíticos, síntese e caracterização dos co-cristais sólidos de alguns antibióticos (fluoroquinolonas) com alguns co-formadores
• Beneficiário: Massao Ionashiro
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/03460-6 - Modificação estrutural de triglicerídeos visando a obtenção de novos monômeros e polímeros por diferentes rotas sintéticas: irradiação de micro-ondas e fotopolimerização
• Beneficiário: Rafael Turra Alarcon
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 17/08820-8 - Síntese e caracterização de biopolímeros a partir de óleos vegetais e glicerol seguindo os princípios da química verde.
• Beneficiário: Gilbert Bannach
• Modalidade de apoio: Auxílio à Pesquisa - Regular