Curcumin-laden amphiphilic chitosan microemulsion with enhanced transdermal delivery, skin compatibility and anti-arthritic activity

Abstract

Transdermal administration can avoid the first-pass effect of liver, improve the bioavailability of drugs and the adaptability of patients. However, there are still many problems, such as low load efficiency, short drug half-life, unfavorable transdermal efficiency, poor skin compatibility, which hinder the development of transdermal administration. In order to solve the above problems, amphiphilic chitosan microemulsion (AC-ME) is developed by using chitosan with hydrophilic carboxyl groups and hydrophobic long alkane chains as surfactant. AC-ME is efficient for drug loading and transdermal delivery, which is demonstrated by extremely high drug loading, improved drug stability and excellent transdermal efficiency. Specifically, the loading amount of curcumin (Cur) can reach up to 3.41 ± 0.13 mg/mL, an increase of approximately 30,000 times compared to its water solution. The light stability of Cur is improved from 43% to 75%. The transdermal process and skin retention of Cur exhibit 1.76-fold and 5.29-fold increase, respectively. Moreover, AC-ME is skin-compatible and does not damage skin structure. Finally, AC-ME can improve the therapeutic effect of Cur and exhibit superb anti-inflammatory effect in the rheumatoid arthritis (RA) model of mice. In a word, AC-ME would be a promising drug carrier for transdermal drug delivery.