Biocomposite of double-walled carbon nanotube-doped alginate gel for biomaterial immobilization

An efficient support for biomaterial immobilization, double-walled carbon nanotube-doped alginate gel (DWCNT–ALG) hybrid composite, was studied in this work. DWCNTs were cut by mixed acids to get a homogeneous dispersion in an aqueous solution. Fourier transform infrared spectroscopy (FTIR) was employed to analyze the structure of shortened DWCNTs. Bovine serum albumin (BSA), the model biomaterial, was immobilized in DWCNT–ALG composites. Mixture of DWCNTs and BSA were suspended in ALG homogenously and then added into a calcium chloride solution dropwise to form biocomposite beads. Transmission and scanning electron microscope (TEM and SEM) images confirmed the adsorption of BSA on DWCNTs and the uniform distribution of DWCNTs in ALG, respectively. Water loss and BSA leakage from the BSA–DWCNT–ALG biocomposites were reduced to 46.48% and 19.28%, respectively, compared with those from BSA–ALG biocomposites. These DWCNT–ALG biocomposites showed high efficiency in BSA immobilization.