title: Utilization of pure nuclear quadrupole resonance spectroscopy for the study of pharmaceutical crystal forms.
abstract: Solid-state physical characterization of a pharmaceutical substance is necessary for successful development and approval of the final product. Different physical analytical techniques are available to do so: X-ray diffraction (XRD), IR, Raman, DSC, TG and NMR. Moreover, all of them detect the presence of excipients perturbing the analysis of the pure substance in low doses. In order to study polymorphism and pseudo polymorphism of drug, this paper introduces possible applications of pure nuclear quadrupole resonance, as a non-destructive technique in qualitative and quantitative approaches. Chlorpropamide and diclofenac sodium were used as examples. Unlike the mentioned techniques, the nuclear quadrupole resonance (NQR) signal of pharmaceutical compounds is not perturbed by the presence of solid excipient or other substances unless they possess resonance frequencies in the same frequency range of the compound studied.
authors.affiliation: Facultad de Matemática, Astronomía y Física, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina.
authors.forename: S C
authors.initials: SC
authors.lastname: Pérez
authors.forename: L
authors.initials: L
authors.lastname: Cerioni
authors.forename: A E
authors.initials: AE
authors.lastname: Wolfenson
authors.forename: S
authors.initials: S
authors.lastname: Faudone
authors.forename: S L
authors.initials: SL
authors.lastname: Cuffini
mesh_terms: D002747:Chlorpropamide / Q000737:chemistry*; D003460:Crystallization; D004008:Diclofenac / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D014961:X-Ray Diffraction
chemical_list: D004008:Diclofenac; D002747:Chlorpropamide