Immobilization of acetylcholinesterase on electrospun poly(acrylic acid)/multi-walled carbon nanotube nanofibrous membranes

Abstract

In this work, poly(acrylic acid) (PAA) and PAA/multi-walled carbon nanotube (MWNTs) nanofibrous membranes are fabricated by electrospinning to immobilize acetylcholinesterase (AChE).3-Aminopropyltriethoxysilane (APTES) and glutaraldehyde are used for surface modification and PAA membrane stabilization in aqueous media. The structure of the nanofibrous membrane was studied by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, thermogravimetric and mechanical analyses. The AChE enzyme was immobilized on the PAA nanofibers with different amounts of MWNTs concentrations from 0 to 5 wt%. The SEM images revealed that the average diameter of the PAA nanofibers was 226 AE 25 nm which was increased by increasing the MWNTs concentration. The tensile strength and modulus of the nanofibrous membranes increased by 1.87 and 4.39 fold respectively after a crosslinking process. The results show that membranes containing MWNTs are a more appropriate support for enzyme immobilization. In comparison to pure PAA, the activity of the sample containing 4 wt% of MWNTs was increased by 5.07 fold. Also, the immobilized enzyme showed excellent reusability even after 10 cycles of washing and samples maintained more than 90% of their original activities. Moreover, the pH and thermal stability of the immobilized enzyme was improved compared to the free enzyme. The results show that a PAA/MWNTs nanofibrous membrane could be counted as a suitable support for AChE immobilization in addition to different applications such as biosensor manufacturing.

Covalent immobilization of acetylcholinesterase on a novel polyacrylic acid‐based nanofiber membrane

“…This result can be attributed to the small impairment of the enzyme conformation upon immobilization. Similar changes in the kinetic parameters of AChE after immobilization have been reported, and the K m values of immobilized AChE were found to be 0.1241 mM on electrospun poly(acrylic acid)/multiwalled carbon nanotube NF [18], 27.24 mM on chitosan-SiO 2 [36], 0.02630 mM on polyacrylamide-functionalized multiwalled carbon nanotube NF [37], 0.0272 mM on Polymethyl Methacrylate NF [38]. Therefore, the immobilization procedure enables the utilization of immobilized enzyme for the immobilization applications.…”

Systematic investigation of parameters of an electrospinning process of poly(acrylic acid) nanofibres using response surface methodology

“…Recently, the nanofibres made of PAA polymer have attracted much attention in various applications. For example, PAA nanofibres can be used to anchor biomacromolecules, such as enzymes and DNA which is required for bioelectronics and biosensor applications [37]. Also, there have been some research studies on the applications of these nanofibres in sensors [22], removal of heavy metals [38], removal of pollutants [39], nanocomposites [40], actuators [41][42][43] and muscle tissue engineering [44].…”

Nano‐CaCO3‐embodied polyacrylicacid/dextran nanocomposites for packaging applications

“…Among all monomers, vinylic‐based monomer, that is, acrylic acid (AA) is generally utilized for this intention because of its easy production, cost effective, less toxic, biodegradable and biocompatible nature . Poly(acrylic acid) (PAA), a water‐soluble polymer has gained considerable interest because of their incredible applications in multiple fields like electrolyte in dry cells, superabsorbent materials, energy storage materials, dye removal, biosensor, and so on . PAA is a biodegradable vinylic‐based aliphatic acid regularly prepared by polymerization of AA in the presence of ammonium persulfate (APS) as an initiator .…”