1 research outputs found
Novel Phenolic Biosensor Based on a Magnetic Polydopamine-Laccase-Nickel Nanoparticle Loaded Carbon Nanofiber Composite
A novel phenolic biosensor was prepared
on the basis of a composite of polydopamine (PDA)-laccase (Lac)-nickel
nanoparticle loaded carbon nanofibers (NiCNFs). First, NiCNFs were
fabricated by a combination of electrospinning and a high temperature
carbonization technique. Subsequently, the magnetic composite was
obtained through one-pot Lac-catalyzed oxidation of dopamine (DA)
in an aqueous suspension containing Lac, NiCNFs, and DA. Finally,
a magnetic glass carbon electrode (MGCE) was employed to separate
and immobilize the composite; the modified electrode was then denoted
as PDA-Lac-NiCNFs/MGCE. Fourier transform infrared (FT-IR) spectra
and cyclic voltammetry (CV) analyses revealed the NiCNFs had good
biocompatibility for Lac immobilization and greatly facilitated the
direct electron transfer between Lac and electrode surface. The immobilized
Lac showed a pair of stable and well-defined redox peaks, and the
electrochemical behavior of Lac was a surface-controlled process in
pH 5.5 acetate buffer solution. The PDA-Lac-NiCNFs/MGCE for biosensing
of catechol exhibited a sensitivity of 25 μA mM<sup>–1</sup> cm<sup>–2</sup>, a detection limit of 0.69 μM (S/N
= 3), and a linear range from 1 μM to 9.1 mM, as well as good
selectivity and stability. Meanwhile, this novel biosensor demonstrated
its promising application in detecting catechol in real water samples