title: Degradation and protection of DNAzymes on human skin.
abstract: DNAzymes are catalytic nucleic acid based molecules that have become a new class of active pharmaceutical ingredients (API). Until now, five DNAzymes have entered clinical trials. Two of them were tested for topical application, whereby dermally applied DNAzymes had been prone to enzymatic degradation. To protect the DNAzymes the enzymatic activity of human skin has to be examined. Therefore, the enzymatic activity of human skin was qualitatively and quantitatively analyzed. Activity similar to that of DNase II could be identified and the specific activity was determined to be 0.59Units/mg. These results were used to develop an in vitro degradation assay to screen different kinds of protective systems on human skin. The chosen protective systems consisted of biodegradable chitosans or polyethylenimine, which forms polyplexes when combined with DNAzymes. The polyplexes were characterized in terms of particle size, zeta potential, stability and degree of complexation. The screening revealed that the protective efficiency of the polyplexes depended on the polycation and the charge ratio (ξ). At a critical ξ ratio between 1.0 and 4.1 and at a maximal zeta potential, sufficient protection of the DNAzyme was achieved. The results of this study will be helpful for the development of a protective dermal drug delivery systems using polyplexes.
authors.affiliation: Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany. Electronic address: Kay.Marquardt@lse.thm.de.
authors.forename: Kay
authors.initials: K
authors.lastname: Marquardt
authors.affiliation: Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany.
authors.forename: Anna-Carola
authors.initials: AC
authors.lastname: Eicher
authors.affiliation: Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany.
authors.forename: Dorota
authors.initials: D
authors.lastname: Dobler
authors.affiliation: Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Höfer
authors.affiliation: Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmidts
authors.affiliation: Pharmaceutical Technology and Biopharmacy, Ketzerbach 63, 35032 Marburg, Philipps-University Marburg, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Schäfer
authors.affiliation: Institute of Laboratory Medicine and Pathobiochemistry, Molecular Diagnostic, Baldinger Strasse, 35043 Marburg, Philipps-University Marburg, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Renz
authors.affiliation: Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390 Giessen, Germany; Faculty of Biology and Chemistry, Justus-Liebig University Giessen, Heinrich-Buff-Ring 17, 35392 Giessen, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Runkel
mesh_terms: D002851:Chromatography, High Pressure Liquid; D021881:DNA, Catalytic / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D008855:Microscopy, Electron, Scanning; D012867:Skin / Q000378:metabolism*
chemical_list: D021881:DNA, Catalytic
keywords: Chitosan; Chitosan (PubChem CID: 21896651); Chitosan oligosaccharide lactate (PubChem CID: 16213812); DNAzyme; DNase; Deoxyribonuclease II (PubChem SID: 135286563); Human skin; Polyethyleneimine (PubChem CID: 9033); Polyethylenimine; Polyplex