Algorithms / Physical Chemistry / Biomedical Engineering / Drug delivery / Drug Use / Humans / Controlled release / Current Density / Transdermal Drug Delivery System / Iontophoresis / Ion Exchange / Electrodes / Cation Exchange / Drug Release / Tacrine / Transdermal Drug Delivery / Humans / Controlled release / Current Density / Transdermal Drug Delivery System / Iontophoresis / Ion Exchange / Electrodes / Cation Exchange / Drug Release / Tacrine / Transdermal Drug Delivery