Solid Microneedles for Transdermal Delivery of Amantadine Hydrochloride and Pramipexole Dihydrochloride

The aim of this project was to study the influence of microneedles on transdermal delivery of amantadine hydrochloride and pramipexole dihydrochloride across porcine ear skin in vitro. Microchannel visualization studies were carried out and characterization of the microchannel depth was performed using confocal laser scanning microscopy (CLSM) to demonstrate microchannel formation following microneedle roller application. We also report, for the first time, the use of TA.XT Plus Texture Analyzer to characterize burst force in pig skin for transdermal drug delivery experiments. This is the force required to rupture pig skin. The mean passive flux of amantadine hydrochloride, determined using a developed LC-MS/MS technique, was 22.38 ± 4.73 µg/cm²/h, while the mean flux following the use of a stainless steel microneedle roller was 49.04 ± 19.77 µg/cm²/h. The mean passive flux of pramipexole dihydrochloride was 134.83 ± 13.66 µg/cm²/h, while the flux following the use of a stainless steel microneedle roller was 134.04 ± 0.98 µg/cm²/h. For both drugs, the difference in flux values following the use of solid stainless steel microneedle roller was not statistically significantly (p > 0.05). Statistical analysis was carried out using the Mann-Whitney Rank sum test.