Iontophoresis - An Approach for Controlled Drug Delivery: A Review

Abstract

The recent approval of lidocaine hydrochloride and epinephrine combined iontophoretic patch (Lidosite ® Vysteris Inc.) for localized pain treatment by FDA has invigorated the gaining interest in iontophoretic drug delivery systems for the transdermal delivery of drugs. This technique of facilitated movement of ions across a membrane under the influence of an externally applied electric potential difference, is one of the most promising physical skin penetration enhancing method. The rationale behind using this technique is the capability of this method to increase the systemic delivery of high molecular weight compounds with controlled input kinetics and minimum inter-subject variability, which is otherwise achieved only when parentral route of administration is used. Recently, good permeation of larger peptides like insulin has been achieved through this technique in combination with chemical enhancers. This review briefly describes the factors which affect iontophoretic drug delivery and summarizes the studies conducted recently using this technique in order to achieve higher systemic absorption of the drugs having low passive diffusion otherwise. The effect of permeation enhancers (chemical enhancers) on iontophoretic flux of drugs has also been described. Present review also provides an insight into reverse iontophoresis. Various parameters which affect the transdermal absorption of drugs through iontophoresis like drug concentration, polarity of drugs, pH of donor solution, presence of co-ions, ionic strength, electrode polarity etc. have also been reviewed in detail.

Iontophoretic Transdermal Delivery of Glycyrrhizin: Effects of pH, Drug Concentration, Co-ions, Current Intensity, and Chemical Enhancers

“…44,45) Chemical enhancers in combination with iontophoresis are known to increase the transdermal permeation rate of macromolecules synergically. 10,46) As for skin toxicity in the combination of iontophoresis and the chemical enhancers, there are controversial results have been reported: some enhancers aggravated iontophoresis-induced skin irritation, 35) and others reduced the skin toxicity. 47,48) In the present study there were no obvious differences in macroscopic observations between sham and current in combination with chemical enhancers-applied skins, however, the in vitro skin permeation system is not relevant to evaluate skin irritation.…”

Mechanical and Baicalin Delivery Properties of Adhesive Matrices for Iontophoretic Flexible Electrodes

“…As we know, the great change of pH values in IF +,FCL and IF −,FCL might induce deterioration of the drug stability [7][8][9]. Hence, an additional pH-controlling layer prepared from the buffer solution (PBS for pH 5.8, 7.2, 7.6 and 8.2, ABS for pH 6.5 or BPBS for pH 9.0), was employed and DLAMs (Fig.…”

“…Baicalin is an acid drug and baicalin ions exhibit a negative charge in the matrices. Therefore, during the iontophoresis more baicalin could permeate across the skin by both repulsion and convective mechanisms from the cathode than from the anode [5][6][7][8][9]. Hence, in the following experiments the baicalin-loaded DLAM was only applied to the FAE cathode.…”

“…Its mechanisms include electrophoresis (electric field charge interaction) [5] and electroosmosis (electric field induced solvent flow) [6]. Detail mechanisms, effecting factors and application of iontophoresis could be found in Refs [7][8][9].…”

Princípios básicos e aplicação da iontoforese na penetração cutânea de fármacos

“…34,35 A baixa variabilidade biológica paciente/paciente promovida pelo controle da corrente elétrica é outra vantagem da iontoforese quando comparada à administração passiva (sem corrente elétrica) de substâncias. 36 Singh et al 37 estudaram o efeito da iontoforese de uma solução salina na função barreira da pele e possíveis ocorrências de irritação local em pessoas de quatro grupos étnicos, analisando a perda de água transepidermal (TEWL), a capacitância e temperatura cutânea. Eles não observaram diferenças significativas dos parâmetros analisados entre os diferentes grupos citados após 4 h de iontoforese.…”