TY - JOUR
T1 - Coated microneedles for transdermal delivery
AU - Gill, Harvinder S.
AU - Prausnitz, Mark R.
N1 - Funding Information:
We would like to thank Dr. Mark Allen for use of the IR and CO 2 lasers in his lab; Richard Shafer, Dr. Shawn Davis, and Ed Birdsell for helpful discussions regarding laser operation; Dr. Jung-Hwan Park for additional helpful discussions; Dr. David Garber (Emory Vaccine Center) for providing the modified vaccinia virus; and Dannae Rowe (MACtac Technical Products) for providing the medical foam tapes used in the microneedle patch fabrication. Mark Prausnitz is the Emerson Lewis Faculty Fellow. This work was supported in part by the National Institutes of Health and took place in the Center for Drug Design, Development and Delivery and the Institute for Bioengineering and Bioscience at the Georgia Institute of Technology.
PY - 2007/2/12
Y1 - 2007/2/12
N2 - Coated microneedles have been shown to deliver proteins and DNA into the skin in a minimally invasive manner. However, detailed studies examining coating methods and their breadth of applicability are lacking. This study's goal was to develop a simple, versatile and controlled microneedle coating process to make uniform coatings on microneedles and establish the breadth of molecules and particles that can be coated onto microneedles. First, microneedles were fabricated from stainless steel sheets as single microneedles or arrays of microneedles. Next, a novel micron-scale dip-coating process and a GRAS coating formulation were designed to reliably produce uniform coatings on both individual and arrays of microneedles. This process was used to coat compounds including calcein, vitamin B, bovine serum albumin and plasmid DNA. Modified vaccinia virus and microparticles of 1 to 20 μm diameter were also coated. Coatings could be localized just to the needle shafts and formulated to dissolve within 20 s in porcine cadaver skin. Histological examination validated that microneedle coatings were delivered into the skin and did not wipe off during insertion. In conclusion, this study presents a simple, versatile, and controllable method to coat microneedles with proteins, DNA, viruses and microparticles for rapid delivery into the skin.
AB - Coated microneedles have been shown to deliver proteins and DNA into the skin in a minimally invasive manner. However, detailed studies examining coating methods and their breadth of applicability are lacking. This study's goal was to develop a simple, versatile and controlled microneedle coating process to make uniform coatings on microneedles and establish the breadth of molecules and particles that can be coated onto microneedles. First, microneedles were fabricated from stainless steel sheets as single microneedles or arrays of microneedles. Next, a novel micron-scale dip-coating process and a GRAS coating formulation were designed to reliably produce uniform coatings on both individual and arrays of microneedles. This process was used to coat compounds including calcein, vitamin B, bovine serum albumin and plasmid DNA. Modified vaccinia virus and microparticles of 1 to 20 μm diameter were also coated. Coatings could be localized just to the needle shafts and formulated to dissolve within 20 s in porcine cadaver skin. Histological examination validated that microneedle coatings were delivered into the skin and did not wipe off during insertion. In conclusion, this study presents a simple, versatile, and controllable method to coat microneedles with proteins, DNA, viruses and microparticles for rapid delivery into the skin.
KW - Dip-coating method
KW - Microfabricated microneedles
KW - Transdermal drug delivery
UR - http://www.scopus.com/inward/record.url?scp=33846492454&partnerID=8YFLogxK
U2 - 10.1016/j.jconrel.2006.10.017
DO - 10.1016/j.jconrel.2006.10.017
M3 - Article
C2 - 17169459
AN - SCOPUS:33846492454
SN - 0168-3659
VL - 117
SP - 227
EP - 237
JO - Journal of Controlled Release
JF - Journal of Controlled Release
IS - 2
ER -