Year-end Sale % OFF 
Abstract
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.
Highlights
The (1–0.015 biosensing the peptide-nanocellulose aerogel conjugate determined by monitoring the reaction between the serine proteases human neutrophil elastase (HNE)
Low density nanocellulosic II aerogels have been successfully prepared from greige cotton by (a) dissolution in calcium thiocyanate octahydrate, which contained 2.5 wt% of lithium chloride; (b) casting; (c) cellulose coagulation and washing; (d) solvent exchange and (e) supercritical carbon dioxide drying, which yield an open porous and interconnected structure
The morphology of the derived aerogels is dominated by the fibrous cellulose II network whose homogeneity is occasionally disrupted by small quantities of undissolved residues, which seem to be well integrated into the aerogel matrix
Summary
Aerogels are solids that feature very low density, high specific surface area and consist of a coherent open-porous network of loosely-packed, bonded particles or fibers [1], which distinguishes. Sensors 2016, 16, 1789 them from other porous materials, like liquid foams, packed beds or open-porous metal foams Their particular morphology in terms of high interconnected porosity (≤99.9 vol%) and large internal surface (≤1000 m2 ·g−1 ) render aerogels promising matrix materials for a variety of applications. Caspase-3 activity [23,24] They have a rich structure/function literature that can be utilized to design enzyme sensors and are central to a number of protease-based diseases and their therapy [8]. The use of nanocellulosic aerogels (NA) as the transducer surface attached to a fluorescent peptide substrate, such as succinyl-alanine-proline-alanine-4-amino-7-methyl-coumarin (Suc-Ala-Pro-Ala-AMC) or succinyl-alanine-alanine-proline-valine-4-amino-7-methyl-coumarin (Suc-Ala-Ala-Pro-Val-AMC) [38], which has selectivity for HNE, offers specificity, and offers a way to detect HNE in chronic wound fluid. The physical properties of the aerogel are suitable for interfacing with a protease sequestrant wound dressing
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
