title: Systematic Analysis of Pharmaceutical Preparations of Chondroitin Sulfate Combined with Glucosamine.
abstract: Glycosaminoglycans are carbohydrate-based compounds widely employed as nutraceuticals or prescribed drugs. Oral formulations of chondroitin sulfate combined with glucosamine sulfate have been increasingly used to treat the symptoms of osteoarthritis and osteoarthrosis. The chondroitin sulfate of these combinations can be obtained from shark or bovine cartilages and hence presents differences regarding the proportions of 4- and 6-sulfatedN-acetyl β-d-galactosamine units. Herein, we proposed a systematic protocol to assess pharmaceutical batches of this combination drug. Chemical analyses on the amounts of chondroitin sulfate and glucosamine in the batches were in accordance with those declared by the manufacturers. Anion-exchange chromatography has proven more effective than electrophoresis to determine the type of chondroitin sulfate present in the combinations and to detect the presence of keratan sulfate, a common contaminant found in batches prepared with shark chondroitin sulfate. 1D NMR spectra revealed the presence of non-sulfated instead of sulfated glucosamine in the formulations and thus in disagreement with the claims declared on the label. Moreover, 1D and 2D NMR analyses allowed a precise determination on the chemical structures of the chondroitin sulfate present in the formulations. The set of analytical tools suggested here could be useful as guidelines to improve the quality of this medication.
authors.affiliation: Laboratório de Tecido Conjuntivo, Hospital Universitário Clementino Fraga Filho and Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro (UFRJ), P.O. Box 68041, Rio de Janeiro RJ 21941-913, Brazil. fgugarc@hotmail.com.
authors.forename: Gustavo R C
authors.initials: GR
authors.lastname: Santos
authors.affiliation: Laboratório de Tecido Conjuntivo, Hospital Universitário Clementino Fraga Filho and Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro (UFRJ), P.O. Box 68041, Rio de Janeiro RJ 21941-913, Brazil. piquet@hucff.ufrj.br.
authors.forename: Adriana A
authors.initials: AA
authors.lastname: Piquet
authors.affiliation: Laboratório de Tecido Conjuntivo, Hospital Universitário Clementino Fraga Filho and Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro (UFRJ), P.O. Box 68041, Rio de Janeiro RJ 21941-913, Brazil. biancaglauser@gmail.com.
authors.forename: Bianca F
authors.initials: BF
authors.lastname: Glauser
authors.affiliation: Laboratório de Tecido Conjuntivo, Hospital Universitário Clementino Fraga Filho and Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro (UFRJ), P.O. Box 68041, Rio de Janeiro RJ 21941-913, Brazil. tovara@gmail.com.
authors.forename: Ana M F
authors.initials: AM
authors.lastname: Tovar
authors.affiliation: Laboratório de Tecido Conjuntivo, Hospital Universitário Clementino Fraga Filho and Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro (UFRJ), P.O. Box 68041, Rio de Janeiro RJ 21941-913, Brazil. marianasa@hucff.ufrj.br.
authors.forename: Mariana S
authors.initials: MS
authors.lastname: Pereira
authors.affiliation: Laboratório de Tecido Conjuntivo, Hospital Universitário Clementino Fraga Filho and Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro (UFRJ), P.O. Box 68041, Rio de Janeiro RJ 21941-913, Brazil. evilanova@hucff.ufrj.br.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Vilanova
authors.affiliation: Laboratório de Tecido Conjuntivo, Hospital Universitário Clementino Fraga Filho and Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro (UFRJ), P.O. Box 68041, Rio de Janeiro RJ 21941-913, Brazil. pmourao@hucff.ufrj.br.
authors.forename: Paulo A S
authors.initials: PA
authors.lastname: Mourão
keywords: arthritis; arthroses; glucosamine sulfate; glycosaminoglycans; nuclear magnetic resonance