Facile one-step synthesis of poly(styrene-glycidyl methacrylate)-Fe3O4 nanocomposite particles and application potency in glucose biosensors

This research is aimed towards a facile one-step preparation of magnetic poly(styrene-glycidyl methacrylate)-Fe3O4 nanocomposite particles named as P(S-GMA)-Fe3O4. The nanocomposite particles are prepared by a simultaneous free-radical copolymerization and co-precipitation of Fe2+ and Fe3+ salts. Two variable w/w ratios of styrene to GMA (98/2 and 96/4) are used. But, the overall copolymer to iron oxide ratio is kept identical. The structural analyses and morphology revealed the uniform distribution of Fe3O4 nanoparticles and the nanocomposites showed paramagnetic property. The potentiality of nanocomposite particles as glucose bisenosors via adsorption of glucose oxidase (GOD) is investigated using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). A comparative analysis of the glucose concentration dependent current response suggested that the modified electrode fabricated from P(S-GMA)-Fe3O4(2) (w/w ratio, 98/2) possessed superior response to other electrodes made from PS, P(S-GMA), PS-Fe3O4 and P(S-GMA)-Fe3O4(4) (w/w ratio, 96/4), respectively. The P(S-GMA)-Fe3O4(2)/GOD/Pt biosensor could measure glucose in the range of 2.2 x 10(- 4) to 6.0 x 10(- 3) M with a sensitivity of 14.47 mu A mM(- 1) and exhibited a detection limit of 5.07 mu M at a signal to noise ratio of 3. The value of Michaelis-Menten constant (K-m) is calculated as 0.019 mM. Overall results indicate that P(S-GMA)-Fe3O4(2) nanocomposite prepared in one-step is suitable for use in glucose biosensors.