The Preparation and Characterization of Alginate–Chitosan Membranes as Solid Support for BTB and Urease Entrapment

Abstract

A study of alginate-chitosan membrane synthesize was done. The membrane was prepared by mixing alginate hydrosol and chitosan hydrosol at mass ratio of 1:1 and pH of 5.28 approximately. Then it was applied for matrix immobilization of urease and bromothymol blue (BTB) by entrapment technique. The physical, chemical, thermal properties of alginate–chitosan membrane and their impact on immobilized urease activity were investigated. The polymer products were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM). It’s showed that alginate-chitosan membrane was formed by electrostatic interaction. The obtained membran has better mechanical properties than original alginat and chitosan membranes. The immobilization urease into alginate-chitosan membrane retained the catalytic activity of the enzyme, as confirmed by color change of BTB indicator after membrane was immersed in substrate solution (urea). Therefore, alginate-chitosan membrane has good characteristics as matrix of enzyme immobilization.

Optical fiber mercury biosensor based on immobilized urease and bromothymol blue onto the alginate-chitosan membrane in the flow-system

“…Here, carboxylic groups of alginates interact with protonated amine groups of chitosan through ionic interactions to form complexes without the addition of crosslinkers at certain conditions and ratios. It was indicated by FTIR spectra of alginate-chitosan PEC at 1550 cm -1 (NH 3 + ), 1577 cm -1, and 1398 cm -1 (-COO -) (Hermanto et al, 2020;Ismillayli et al, 2020;Kulig et al, 2016). This strong ionic bonding was the main interaction inside the network.…”

Transparent Membrane of Polyelectrolyte Complex Doped with 2,6-Dichlorophenol-Indophenol as an Optical Sensor for Colorimetric Measurements of Ascorbic acid

“…Here, the morphology of the alginatechitosan membrane mixed was less homogeneous, it can be observed that the transparent membrane surface of the alginate-chitosan shows a fibrous structure with a rough morphology and irregular shape, which is a network of electrostatic interactions of alginate and chitosan. The likeness of its surface morphology has been described at previously work 6,9 .…”

“…The membrane was prepared from hydrosols of chitosan and alginate, as described by Hermanto et al 6,9 . The scanning electron microscope (SEM) study was carried out on a transparent PEC membrane after being coated with gold palladium on SEM (Joel LV 5600 USA model) to evaluate the morphology and structure of membrane surface, as shown in Fig.…”

“…In the last decade, PEC has drawn attention from various scientific disciplines to be applied as a supporting matrix. PEC is an association complex formed between polymers that have polyions with opposite charges trough electrostatic interaction 6 . Alginate which is polyanionic and polycationic chitosan when dissolved in the right conditions can interact each other through carboxyl groups from alginate and amino groups from chitosan 7 .…”

Conducting Matrices of the Poly(-O-Toluidine, PTOL) Film for Immobilizing Uricase

“…Changes in pH and the redox potential of the environment affect the electronic conductivity of the conducting polymer (Gerard et al, 2002). Immobilization of this enzyme in appropriate matrix allows the enzyme was used several times while maintaining its catalytic activity (Hermanto et al, 2020;. In addition, immobilized enzymes on conducting polymer facilitate the electron transfer from the active site of an enzyme that redox reaction takes place to analyte solution, providing good detectability and fast response as redox reaction of the substrate.…”