title: An interfacially plasticized electro-responsive hydrogel for transdermal electro-activated and modulated (TEAM) drug delivery.
abstract: This paper highlights the use of hydrogels in controlled drug delivery, and their application in stimuli responsive, especially electro-responsive, drug release. electro-conductive hydrogels (ECHs) displaying electro-responsive drug release were synthesized from semi-interpenetrating networks (semi-IPNs) containing a poly(ethyleneimine) (PEI) and 1-vinylimidazole (VI) polymer blend as the novel electro-active species. The semi-IPNs are systems comprised of polyacrylic acid (PAA) and poly(vinyl alcohol) (PVA). This paper attempts to investigate the various attributes of the electro-responsive ECHs, through institution of a statistical experimental design. The construction of a Box-Behnken design model was employed for the systematic optimization of the ECH composition. The design model comprised of three variables, viz. poly(ethyleneimine) volume; 1-vinylimidazole volume; and applied voltage, critical to the success of the formulation. Electro-responsive drug release was determined on formulations exposed to varying environments to ascertain the optimal environment for the said desired release. A comparison method of formulation water content and swelling through gravimetric analysis was also conducted. Matrix resilience profiles were obtained as an insight to the ability of the ECH to revert to its original structure following applied stress. Response surface and contour plots were constructed for various response variables, namely electro-responsive drug release, matrix resilience and degree of swelling. The outcomes of the study demonstrated the success of electro-responsive drug release. The findings of the study can be utilized for the development of electro-responsive delivery systems of other drugs for the safer and effective drug delivery. Volumes of poly(ethyleneimine) (>2.6 mL) and 1-vinylimidazole (>0.7 mL), resulted in ideal therapeutic electro-responsive drug release (0.8 mg) for indomethacin. Lower amounts of poly(ethyleneimine) and amounts of 1-vinylimidazole ranging from 0.2 to 0.74 mL are consistent with greater than 1.6 mg release per stimulation. Swelling of <25-45% was seen.
authors.affiliation: University of the Witwatersrand, Faculty of Health Sciences, Department of Pharmacy and Pharmacology, 7 York Road, Parktown, Johannesburg 2193, South Africa.
authors.forename: Sunaina
authors.initials: S
authors.lastname: Indermun
authors.affiliation: University of the Witwatersrand, Faculty of Health Sciences, Department of Pharmacy and Pharmacology, 7 York Road, Parktown, Johannesburg 2193, South Africa.
authors.forename: Yahya E
authors.initials: YE
authors.lastname: Choonara
authors.affiliation: University of the Witwatersrand, Faculty of Health Sciences, Department of Pharmacy and Pharmacology, 7 York Road, Parktown, Johannesburg 2193, South Africa.
authors.forename: Pradeep
authors.initials: P
authors.lastname: Kumar
authors.affiliation: University of the Witwatersrand, Faculty of Health Sciences, Department of Pharmacy and Pharmacology, 7 York Road, Parktown, Johannesburg 2193, South Africa.
authors.forename: Lisa C
authors.initials: LC
authors.lastname: du Toit
authors.affiliation: University of the Witwatersrand, Faculty of Health Sciences, Division of Neurosciences, Department of Neurology, 7 York Road, Parktown, Johannesburg 2193, South Africa.
authors.forename: Girish
authors.initials: G
authors.lastname: Modi
authors.affiliation: MESA+Institute for Nanotechnology, University of Twente, 7500AE Enschede, The Netherlands.
authors.forename: Regina
authors.initials: R
authors.lastname: Luttge
authors.affiliation: University of the Witwatersrand, Faculty of Health Sciences, Department of Pharmacy and Pharmacology, 7 York Road, Parktown, Johannesburg 2193, South Africa. Electronic address: viness.pillay@wits.ac.za.
authors.forename: Viness
authors.initials: V
authors.lastname: Pillay
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000379:methods; D016503:Drug Delivery Systems; D055664:Electrochemical Techniques; D020100:Hydrogels; D007093:Imidazoles / Q000737:chemistry; D007213:Indomethacin / Q000008:administration & dosage* / Q000737:chemistry; D010968:Plasticizers / Q000737:chemistry; D011094:Polyethyleneimine / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011142:Polyvinyl Alcohol / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D020100:Hydrogels; D007093:Imidazoles; D010968:Plasticizers; D011108:Polymers; C006903:carbopol 940; D011142:Polyvinyl Alcohol; D011094:Polyethyleneimine; C425704:N-vinylimidazole; D007213:Indomethacin
keywords: 1-Vinylimidazole; Bipolymeric interfacially plasticized electro-responsive hydrogel; Electro-conductive hydrogels; Poly(ethyleneimine); Semi-interpenetrating networks; Transdermal electro-activated and modulated drug release