title: In vitro evaluation of calcium alginate gels as matrix for iontophoresis electrodes.
abstract: Calcium alginate gel has some unique properties, such as the capability to keep the drugs, bioadhesiveness, safety, and low cost. The purpose of this study is to determine whether calcium alginate gel can be used as a matrix of electrodes for iontophoresis (IOP). We measured the concentration of lidocaine transported from calcium alginate gels with various concentrations of alginic acid using an in vitro experimental cell with square-wave alternating current (AC) application. Temperature and pH changes were also determined during AC-IOP. The results revealed that lidocaine was released from calcium alginate gels at concentrations nearly 1.71-fold larger at 5 V, 60 min after AC application than in the case of passive diffusion. Lidocaine transport depended on the alginic acid concentration in the gels. Although there were slight increases in temperature and pH, chemical and thermal burns were not severe enough to be a concern. In conclusion, the calcium alginate gel can be used as a possible matrix for IOP electrodes.
authors.affiliation: Section of Anesthesiology and Clinical Physiology, Department of Oral Restitution, Division of Oral Health Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, JAPAN.
authors.forename: Haruka
authors.initials: H
authors.lastname: Haida
authors.forename: Shizuka
authors.initials: S
authors.lastname: Ando
authors.forename: Saori
authors.initials: S
authors.lastname: Ogami
authors.forename: Ryo
authors.initials: R
authors.lastname: Wakita
authors.forename: Hikaru
authors.initials: H
authors.lastname: Kohase
authors.forename: Norio
authors.initials: N
authors.lastname: Saito
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Yoshioka
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Ikoma
authors.forename: Junzo
authors.initials: J
authors.lastname: Tanaka
authors.forename: Masahiro
authors.initials: M
authors.lastname: Umino
authors.forename: Haruhisa
authors.initials: H
authors.lastname: Fukayama
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000779:Anesthetics, Local / Q000008:administration & dosage; D004058:Diffusion; D016503:Drug Delivery Systems / Q000295:instrumentation*; D004566:Electrodes; D004867:Equipment Design; D005782:Gels; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007478:Iontophoresis / Q000295:instrumentation* / Q000379:methods; D008012:Lidocaine / Q000008:administration & dosage; D008422:Materials Testing; D013696:Temperature; D013997:Time Factors
chemical_list: D000464:Alginates; D000779:Anesthetics, Local; D005782:Gels; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D008012:Lidocaine