Preparation, Characterization and Activity of a Peptide-Cellulosic Aerogel Protease Sensor from Cotton

Sensors

Falk Liebner¹  Nicole Pircher¹  Nicolette T. Prevost²  J. Vincent Edwards²  Brian D. Condon²  Krystal R. Fontenot² 

[1] Division of Chemistry of Renewable Resources, University of Natural Resources and Life Sciences Vienna, Konrad-Lorenz-Straße 24, Tulln an der Donau A-3430, Austria;Southern Regional Research Center, USDA, New Orleans, LA 70124, USA;

关键词: elastase peptide;    cellulosic aerogels;    human neutrophil elastase;    biosensor;    chronic wounds;   

DOI  :  10.3390/s16111789

来源: DOAJ

【 摘 要 】

Nanocellulosic aerogels (NA) provide a lightweight biocompatible material with structural properties, like interconnected high porosity and specific surface area, suitable for biosensor design. We report here the preparation, characterization and activity of peptide-nanocellulose aerogels (PepNA) made from unprocessed cotton and designed with protease detection activity. Low-density cellulosic aerogels were prepared from greige cotton by employing calcium thiocyanate octahydrate/lithium chloride as a direct cellulose dissolving medium. Subsequent casting, coagulation, solvent exchange and supercritical carbon dioxide drying afforded homogeneous cellulose II aerogels of fibrous morphology. The cotton-based aerogel had a porosity of 99% largely dominated by mesopores (2–50 nm) and an internal surface of 163 m2·g−1. A fluorescent tripeptide-substrate (succinyl-alanine-proline-alanine-4-amino-7-methyl-coumarin) was tethered to NA by (1) esterification of cellulose C6 surface hydroxyl groups with glycidyl-fluorenylmethyloxycarbonyl (FMOC), (2) deprotection and (3) coupling of the immobilized glycine with the tripeptide. Characterization of the NA and PepNA included techniques, such as elemental analysis, mass spectral analysis, attenuated total reflectance infrared imaging, nitrogen adsorption, scanning electron microscopy and bioactivity studies. The degree of substitution of the peptide analog attached to the anhydroglucose units of PepNA was 0.015. The findings from mass spectral analysis and attenuated total reflectance infrared imaging indicated that the peptide substrate was immobilized on to the surface of the NA. Nitrogen adsorption revealed a high specific surface area and a highly porous system, which supports the open porous structure observed from scanning electron microscopy images. Bioactivity studies of PepNA revealed a detection sensitivity of 0.13 units/milliliter for human neutrophil elastase, a diagnostic biomarker for inflammatory diseases. The physical properties of the aerogel are suitable for interfacing with an intelligent protease sequestrant wound dressing.

【 授权许可】

Unknown