Experimental Study Of Low-frequency And External Electric Field For Transdermal Drug Delivery

Currently, Diclofenac sodium is commonly used clinically as a powerful non-steroidal anti-inflammatory and analgesic drugs (NSAIDs). The drug is a commonly used in treating and easing acute attack or persistent swelling and pain of variety of chronic joint diseases, such as Rheumatoid Arthritis and Spondyloarthropathy. Applying transdermal drug delivery in vitro can avoid first-pass effect on the liver and damage to gastrointestinal degradation. At the same time, under the influence of Stratum corneum structure, The amount of natural infiltration is very small, often cannot reach to clinical purposes. Physical methods permeation is primarily changes the cuticle structure of the skin through a variety of physical methods, and lets the drugs through the cuticle more easily. Transdermal Drug Delivery System, also known as Transdermal Therapeutic System, is a new way of noninvasive dosing, which is directly effect on the lesion site through the skin. The key of Transdermal Drug Delivery System is not only promoting drug penetration but also avoiding the stimulation on skin. Therefore, physical penetration has great advantages over chemical penetration. Physical factors such as low frequency ultrasound can increase the permeability of the skin. The composite of external electric field and ultrasound transform structure of stratum corneum, and expanded skin pores or generate new channels to improving the skin’s permeability.Because of the single of conventional transdermal drug delivery and limitation of traditional experimental device, the results are poor. In order to solve above problems and to meet the requirements of composite penetration, this paper designs new experimental device of composite physics penetration and studies experiment of Low-frequency Ultrasound and Electric field acting alone and Ultrasound complex with external electric field joint affecting, and the permeability of Non-steroidal drugs, Diclofenac sodium, through the skin. By doing experiments, observe the effect of frequency, as well as the effect of intensity, duration and electric field intensity. The main contents of the research are as follows:1In order to improve the limitations of the basic diffusion cells and meet the functional requirements with the composite field physical permeation, research and design the new experiments device of complex physics transdermal delivery;2Low-frequency ultrasound alone promote drug percutaneous absorption experiments: by orthogonal experiment method, low-frequency ultrasonic frequency, intensity and permeation time as affecting factors, permeation of Diclofenac sodium as an indicator of the experiment。And the optimized combination obtained by orthogonal design was composed of ultrasonic frequency (21kHz), intensity (0.75W/cm2) and duration (15min).3External electric field composite of Low-frequency ultrasound experiments jointly promote drug percutaneous absorption: under the method of orthogonal design, ultrasonic frequency, intensity, the strength of electric field and penetration time as affecting factors, researching the penetration amount of Diclofenac sodium;4Comprehensive analyses of results of orthogonal experiment, drawing conclusions as follows: the penetration effect of Ultrasound complex external electric field in vitro percutaneous penetration is better than the Ultrasound penetration alone.