Solution Viscosity‐Mediated Structural Control of Nanofibrous Sponge for RNA Separation and Purification

Abstract

Engineering 3D nanofibrous monolithic materials with a controllable porous channel structure and chemical activity is promising for the rapid and efficient separation of environmentally sensitive biomacromolecules such as RNA. Herein, freeze-drying method via regulating the viscosity of nanofiber dispersions is developed to fabricate nanofibrous sponges (NFSs) with 3D structures of microsphere, lamella, and honeycomb by combining poly(vinyl alcohol-co-ethylene) (PVA-co-PE) nanofibers with chitosan (CS) and polyethyleneimine (PEI) in dispersions. Among sponges, a honeycomb nanofibrous sponge (HNFS) possesses highly oriented open-cells and optimal performance, including water permeability of 7.431 × 10 3 L h m −2 at 1 psi, static saturated capacity of 887.6 mg g −1 , dynamic capacity of 763.2 mg g −1 at a flow rate of 1 mm min −1 , and mechanical robustness, superior to reported state-ofthe-art ion-exchange chromatography materials. Furthermore, HNFS-packed chromatographic, funnel, and centrifugal columns present exceptional performance and broad applicability in rapid-separation of RNA from model solution and diverse organisms without degradation. They are attributed to the highly oriented open-cell structure and high-density adsorption ligands on the surface of nanofibrous cell walls. This work provides a facile approach to design advanced NFSs with versatile physicochemical structure and outstanding performance.

Covalently Interconnected Thermoplastic Polymeric Nanofiber/Carbon Nanotube Composite Nanofibrous Aerogels for Piezoresistive Sensors

“…As for the un-cross-linked EVOH/MWCNTs composite aerogel, the characteristic peaks related to MWCNTs appeared at 3450 and 1635 cm –1 , corresponding to the stretching vibration of the graphite structure of MWCNTs skeleton and the stretching vibration of −OH, respectively, suggesting the successful introduction of MWCNTs. Furthermore, a new peak at 1090 cm –1 (C–O–C) was detected in cross-linked EVOH/MWCNTs composite nanofibrous aerogels, confirming the successful cross-linking reaction of hydroxyl groups with the aldehyde groups . Also comparing to un-cross-linked EVOH aerogel, cross-linked EVOH aerogel and cross-linked EVOH/MWCNTs composite aerogel, the peak intensity of cross-linked EVOH/MWCNTs composite aerogel at 1090 cm –1 was larger than that of cross-linked EVOH aerogel at 1090 cm –1 , despite the decrease in the amount of EVOH nanofibers in cross-linked EVOH/MWCNTs composite aerogel, which indirectly indicated that MWCNTs were also involved in hydroxyl aldehyde condensation reaction.…”

“…Furthermore, a new peak at 1090 cm −1 (C−O− C) was detected in cross-linked EVOH/MWCNTs composite nanofibrous aerogels, confirming the successful cross-linking reaction of hydroxyl groups with the aldehyde groups. 60 Also comparing to un-cross-linked EVOH aerogel, cross-linked EVOH aerogel and cross-linked EVOH/MWCNTs composite aerogel, the peak intensity of cross-linked EVOH/MWCNTs composite aerogel at 1090 cm −1 was larger than that of crosslinked EVOH aerogel at 1090 cm −1 , despite the decrease in the amount of EVOH nanofibers in cross-linked EVOH/ MWCNTs composite aerogel, which indirectly indicated that MWCNTs were also involved in hydroxyl aldehyde condensation reaction.…”

High‐Yield of Nucleic Acid Adsorption via Poly(Vinyl Alcohol‐co‐Ethylene) Nanofiber‐Based Anion‐Exchange Chitosan Aerogel Membrane with Controllable Porosity

“…[ 19,20 ] Among numerous porous aerogels for adsorbents, chitosan (CS) aerogel with high porosity, large specific surface area, and biocompatibility is particularly suitable for the adsorption of biomolecules in comparison to synthetic materials. [ 21 ] By controlling the condition of the gelation process (freezing temperature and solution viscosity), pore size and morphology of chitosan aerogel can be intentionally tailored, [ 22–24 ] in which the large surface area of aerogels is modified with different functional groups such as imide, [ 25 ] amine, [ 21,24 ] methyl, [ 26 ] and carbamate [ 27 ] for various applications of molecular adsorption. Therein, the cellulose‐based chitosan aerogel has widely been studied in the field of purification and separation of proteins, [ 28,29 ] whereas cellulose‐based chitosan adsorbents have to be modified with ligands in a relatively low adsorption efficiency and capacity, which have hindered large‐scale application in biomolecule adsorption.…”

“…Nucleic acids, viz., ribonucleic acid (RNA) and deoxyribonucleic acid (DNA), known as genetic information carriers, have wide applications in various fields such as forensic science, size and morphology of chitosan aerogel can be intentionally tailored, [22][23][24] in which the large surface area of aerogels is modified with different functional groups such as imide, [25] amine, [21,24] methyl, [26] and carbamate [27] for various applications of molecular adsorption. Therein, the cellulose-based chitosan aerogel has widely been studied in the field of purification and separation of proteins, [28,29] whereas cellulose-based chitosan adsorbents have to be modified with ligands in a relatively low adsorption efficiency and capacity, which have hindered largescale application in biomolecule adsorption.…”

An EVOH nanofibrous sterile membrane with a robust and antifouling surface for high-performance sterile filtration via glutaraldehyde crosslinking and a plasma-assisted process

“…The crosslinked EVOH presented excellent chemical stability and water-resistance, which was insoluble in all solvents. 17 However, the poor hydrophilicity of crosslinked EVOH results in weak antifouling performance for biological macromolecules. [18][19][20] As a result, constructing EVOH nanofibrous membranes with both hydrothermal stability and an antifouling surface is a promising strategy to prepare high-performance sterile membranes.…”