title: Quantitative determination of fucoidan using polyion-sensitive membrane electrodes.
abstract: The use of polyanion and polycation-sensitive membrane electrodes to detect five different preparations of fucoidan is described. Unlike linear polyanionic molecules previously measured with polymer membrane-based electrochemical sensors, fucoidans from marine brown algae are all highly branched, sulfated polysaccharides with varying charge densities and structures, depending on the species of seaweed, method of extraction used and extent of purification. When tridodecylmethylammonium (TDMA) was used as the ion-exchanger, a large, non-equilibrium EMF response was observed over a concentration range of 0.5-50 μg mL(-1) fucoidan. Fucoidan was also measured by titration with polycationic protamine, using a dinonylnaphthalene sulfonate (DNNS)-doped membrane electrode as the potentiometric endpoint detector. Potentiometric titration was used to determine the binding ratio between protamine and fucoidan at the neutralization endpoint for each fucoidan preparation. This binding ratio was then used to successfully determine the fucoidan content of commercially available nutritional supplements. Fucoidan was also measured in undiluted blood serum, demonstrating that this method may be applicable for measuring fucoidan for clinical applications.
authors.affiliation: Department of Chemistry, Eastern University, 1300 Eagle Rd., St. Davids, PA 19087, United States.
authors.forename: Ji Min
authors.initials: JM
authors.lastname: Kim
authors.affiliation: Department of Chemistry, Eastern University, 1300 Eagle Rd., St. Davids, PA 19087, United States.
authors.forename: Loc
authors.initials: L
authors.lastname: Nguyen
authors.affiliation: Department of Chemistry, Eastern University, 1300 Eagle Rd., St. Davids, PA 19087, United States.
authors.forename: Mary Frances
authors.initials: MF
authors.lastname: Barr
authors.affiliation: Department of Chemistry, Eastern University, 1300 Eagle Rd., St. Davids, PA 19087, United States.
authors.forename: Michael
authors.initials: M
authors.lastname: Morabito
authors.affiliation: Marinova Pty Ltd., 249 Kennedy Drive, Cambridge, Tasmania 7170, Australia.
authors.forename: Damien
authors.initials: D
authors.lastname: Stringer
authors.affiliation: Marinova Pty Ltd., 249 Kennedy Drive, Cambridge, Tasmania 7170, Australia.
authors.forename: J Helen
authors.initials: JH
authors.lastname: Fitton
authors.affiliation: Department of Chemistry, Eastern University, 1300 Eagle Rd., St. Davids, PA 19087, United States. Electronic address: kmowery@eastern.edu.
authors.forename: Kelly A
authors.initials: KA
authors.lastname: Mowery
mesh_terms: D000925:Anticoagulants / Q000032:analysis / Q000097:blood; D000970:Antineoplastic Agents / Q000032:analysis* / Q000097:blood*; D019587:Dietary Supplements / Q000032:analysis*; D004566:Electrodes; D006801:Humans; D007477:Ions / Q000737:chemistry; D008567:Membranes, Artificial; D009281:Naphthalenes / Q000737:chemistry; D011134:Polysaccharides / Q000032:analysis* / Q000097:blood*; D011199:Potentiometry / Q000295:instrumentation*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012624:Seaweed / Q000737:chemistry; D013451:Sulfonic Acids / Q000737:chemistry
chemical_list: D000925:Anticoagulants; D000970:Antineoplastic Agents; D007477:Ions; D008567:Membranes, Artificial; D009281:Naphthalenes; D011134:Polysaccharides; D000644:Quaternary Ammonium Compounds; D013451:Sulfonic Acids; C009543:tridodecylmethylammonium; C007789:fucoidan
keywords: Fucoidan; Polyion-sensitive electrode; Potentiometric titration; Potentiometry