caa a22 4500 445311622 CHVBK 20180317142632.0 cr unu---uuuuu 170323e20110101xx s 000 0 eng 10.1007/s11095-010-0122-x doi (NATIONALLICENCE)springer-10.1007/s11095-010-0122-x Formation and Closure of Microchannels in Skin Following Microporation [Elektronische Daten] [Haripriya Kalluri, Ajay Banga] ABSTRACT: Purpose: To characterize the microchannels created in hairless rat skin by microneedles and investigate their closure following exposure to different occlusive conditions. Methods: Maltose microneedles were characterized by scanning electron microscopy. The microchannels created and their closure when exposed to different conditions was investigated using a variety of techniques. Results: Microscopic imaging indicates a pyramidal geometry of maltose microneedles with an average length of 559 ± 14μm and tip radius of 4μm. Upon insertion into skin, they created microchannels with an average surface diameter of 60μm and an average depth of 160 ± 20μm as observed by histological sectioning and confocal microscopy. Skin recovers its barrier function within 3-4hrs, and microchannels closed within 15hrs of poration when exposed to environment. However, when occluded, the microchannels remained open for up to 72hrs in vivo, as observed by calcein imaging, transepidermal water loss measurements and methylene blue staining. Conclusion: Maltose microneedles penetrated the stratum corneum barrier and created microchannels in skin which completely close within 15hrs after poration. However, under occluded conditions, barrier recovery can be delayed for up to 72hrs in vivo. Springer Science+Business Media, LLC, 2010 microchannels nationallicence microneedles nationallicence microporation nationallicence pore closure nationallicence transdermal delivery nationallicence Kalluri Haripriya Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Mercer University, 3001 Mercer University Drive, 30341, Atlanta, Georgia, USA aut Banga Ajay Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Mercer University, 3001 Mercer University Drive, 30341, Atlanta, Georgia, USA aut Pharmaceutical Research Springer US; http://www.springer-ny.com 28/1(2011-01-01), 82-94 0724-8741 28:1<82 2011 28 11095 https://doi.org/10.1007/s11095-010-0122-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11095-010-0122-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kalluri Haripriya Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Mercer University, 3001 Mercer University Drive, 30341, Atlanta, Georgia, USA aut NATIONALLICENCE 700 1- Banga Ajay Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Mercer University, 3001 Mercer University Drive, 30341, Atlanta, Georgia, USA aut NATIONALLICENCE 773 0- Pharmaceutical Research Springer US; http://www.springer-ny.com 28/1(2011-01-01), 82-94 0724-8741 28:1<82 2011 28 11095 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer