Title:Microneedle-Assisted Percutaneous Transport of Magnesium Sulfate
VOLUME: 17 ISSUE: 2
Author(s):Karna B. Ghimirey and Kevin Ita*
Affiliation:College of Pharmacy Touro University, Mare Island-Vallejo California, CA 94592, College of Pharmacy Touro University, Mare Island-Vallejo California, CA 94592
Keywords:Magnesium sulfate, inductively coupled plasma-optical emission spectroscopy, transdermal flux, microneedle
roller, confocal microscopy, microchannels.
Abstract:
Objective: In vitro diffusion experiments were performed to assess the permeation of magnesium
sulfate across pig skin.
Methods: The mean thickness of the dermatomed porcine skin was 648 ± 12 µm. Magnesium concentration
was measured using inductively coupled plasma-optical emission spectroscopy. Transdermal
flux of magnesium sulfate across MN-treated and untreated porcine skin was obtained from the slope of
the steady-state linear portion of cumulative amount versus time curve.
Results: Statistical analysis of the results was done with Student’s t-test. The transdermal flux of magnesium
sulfate across microneedle-treated porcine skin was 134.19 ± 2.4 µg/cm2/h and transdermal flux
across untreated porcine skin was 4.64 ± 0.05 µg/cm2/h. Confocal microscopy was used to visualize the
microchannels created by a solid microneedle roller (500 µm).
Conclusion: From our confocal microscopy studies, it was evident that the 500 μm long microneedles
disrupted the stratum corneum and created microchannels measuring 191 ± 37 µm. The increase in
transdermal flux across the microneedle-treated skin was statistically significant compared to that of
controls, i.e., without the application of microneedles. With the application of microneedles, the transdermal
flux of magnesium permeated over 12 h was approximately 33-fold higher in comparison to
passive diffusion across an intact stratum corneum.