A norfloxacin-nicotinic acid cocrystal: Mechanochemical synthesis, thermal and structural characterization and solubility assays

Author(s)

Ferreira, Patricia Osorio ^{[1, 2]} ; de Almeida, Amanda Cosmo ^{[1, 2]} ; dos Santos, Everton Carvalho ^[2] ; Droppa Junior, Roosevelt ^[3] ; Ferreira, Fabio Furlan ^[3] ; Kogawa, Ana Carolina ^[4] ; Caires, Flavio Junior ^{[1, 2]}

Affiliation

^[1] Sao Paulo State Univ UNESP, Inst Chem, BR-14800060 Araraquara, SP - Brazil

^[2] Sao Paulo State Univ UNESP, Sch Sci, BR-17033260 Bauru, SP - Brazil

^[3] Fed Univ ABC UFABC, Ctr Nat & Human Sci, BR-09210580 Santo Andre, SP - Brazil

^[4] Fed Univ Goias UFG, Sch Pharm, BR-74605170 Goiania, Go - Brazil

• Document type: Journal article
• Source: Thermochimica Acta; v. 694, DEC 2020.
• Web of Science Citations: 0

Abstract

This work reports the mechanochemical synthesis and characterization of a cocrystal formed by norfloxacin (NOR) and nicotinic acid (NCA). The thermal analysis provided the thermal stability and appropriated stoichiometry of NOR-NCA cocrystal. In addition, the crystalline structure and the coordination sites were obtained through Fourier-transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRPD). This allowed the determination of NOR-NCA interaction in the cocrystal state: the amine group of NOR interacts simultaneously with the aromatic nitrogen and the hydroxyl of the carboxyl group of NCA. Moreover, NOR-NCA crystallized in the monoclinic crystal system, space group Pa, and Z = 4, Z' = 2. Finally, solubility assays showed an increase of NOR solubility of 2 times in pH 6.1 buffer solution. On the other hand, the cocrystal did not show a significant change in NOR solubility in pH 3.0 buffer solution, while presented a slight decrease in pH 8.5 buffer solution, which shows a pH-dependency. (AU)

• FAPESP's process: 18/24378-6 - Synthesis, characterization and thermoanalytical study of Valsartan, Candesartan Cilexetil and Olmesartan medoxomil co-crystals
• Grantee: Flávio Junior Caires
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/14936-9 - Preparation, characterization and thermoanalytical studies of heterogeneous catalysts of double selenates of Mg/Co and Mg/Cu in biodiesel production using different oils
• Grantee: Massao Ionashiro
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/09022-7 - Thermoanalytical studies, synthesis and characterization of the solid co-crystals of antibiotics (fluoroquinolones) with some co-formers
• Grantee: Massao Ionashiro
• Support Opportunities: Regular Research Grants