Physical methods for topical skin drug delivery: concepts and applications

Author(s)

Petrilli, Raquel ; Vianna Lopez, Renata Fonseca

• Document type: Journal article
• Source: Brazilian Journal of Pharmaceutical Sciences; v. 54, p. 19-pg., 2018-01-01.

Abstract

Topical drug delivery is an interesting approach to treat skin diseases and to avoid pain and low patient compliance in cases where a systemic delivery is required. However, the stratum corneum, which is the outermost skin layer, strongly protects the body from the entrance of substances, especially those hydrophilic. In this context, different physical methods have been studied to overcome the stratum corneum barrier and facilitate penetration of drugs into or through the skin. Among them, iontophoresis, low-frequency ultrasound and microneedles have been widely employed for transdermal drug delivery. More recently, they are also studied to aid in the treatment of dermatological disorders, such as skin tumors and inflammation. Basically, iontophoresis refers to the movement of charged and non-charged hydrophilic molecules through the skin due to the application of a low constant electric current and the contributions of electromigration and electroosmosis. In low-frequency ultrasound, cavitation is the main mechanism for skin permeabilization that consists on the formation of microbubbles that disorganize the stratum corneum. Microneedles are microprojections, minimally invasive, that can be designed with different lengths, materials and geometry to increase skin permeability. In this review, concepts, mechanisms and applications of these three physical methods will be presented and discussed with focus on their use in dermatological treatments. Moreover, comparative studies using different physical methods will be presented and also some clinical perspectives will be addressed. (AU)

• FAPESP's process: 14/22451-7 - Sustained drug delivery systems targeting the epithelial tissue
• Grantee: Renata Fonseca Vianna Lopez
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/05930-7 - Influence of iontophoresis and ultrasound on the release of drugs from dendrimeric liquid crystals
• Grantee: Raquel Petrilli
• Support Opportunities: Scholarships in Brazil - Post-Doctoral