TiO2 nanoparticle modified organ-like Ti3C2 MXene nanocomposite encapsulating hemoglobin for a mediator-free biosensor with excellent performances.
TiO2 nanoparticle modified organ-like Ti3C2 MXene (TiO2-Ti3C2) nanocomposite has been synthesized and then used to immobilize hemoglobin (Hb) to fabricate a mediator-free biosensor. The morphology and structure of TiO2-Ti3C2 nanocomposite were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Spectroscopic and electrochemical results revealed that TiO2-Ti3C2 nanocomposite is an excellent immobilization matrix with biocompatibility for redox protein, affording good protein bioactivity and stability. Due to the special organ-like hybrid structure of TiO2-Ti3C2, the direct electron transfer of Hb is facilitated and the prepared biosensors displayed good performance for the detection of H2O2 with a wide linear range of 0.1-380 μM for H2O2 (sensitivity of 447.3 μA mM(-1) cm(-2)), an extremely low detection limit of 14 nM for H2O2. Especially, numerous TiO2 nanoparticles with excellent biocompatibility on the surface of the nanocomposite may provide a protective microenvironment for Hb to make the prepared biosensor improve long-term stability. The TiO2-Ti3C2 based biosensor retains 94.6% of the initial response to H2O2 after 60-day storage. TiO2-Ti3C2 nanocomposite could be a promising matrix for the fabrication of mediator-free biosensors, and might find wide potential applications in environmental analysis and biomedical detection.
Key Laboratory of Auxiliary Chemistry & Technology for Chemical Industry, Ministry of Education, Shaanxi University of Science & Technology, Xi'an 710021, PR China. Electronic address: wangf@sust.edu.cn.
Fen
F
Wang
Key Laboratory of Auxiliary Chemistry & Technology for Chemical Industry, Ministry of Education, Shaanxi University of Science & Technology, Xi'an 710021, PR China. Electronic address: ych488@163.com.
ChenHui
C
Yang
Key Laboratory of Auxiliary Chemistry & Technology for Chemical Industry, Ministry of Education, Shaanxi University of Science & Technology, Xi'an 710021, PR China.
Max
M
Duan
Key Laboratory of Auxiliary Chemistry & Technology for Chemical Industry, Ministry of Education, Shaanxi University of Science & Technology, Xi'an 710021, PR China.
Yi
Y
Tang
Key Laboratory of Auxiliary Chemistry & Technology for Chemical Industry, Ministry of Education, Shaanxi University of Science & Technology, Xi'an 710021, PR China.
JianFeng
J
Zhu
D000327:Adsorption; D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation*; D002417:Cattle; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006454:Hemoglobins / Q000032:analysis / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D014025:Titanium / Q000737:chemistry*
D006454:Hemoglobins; C096521:titanium carbide; C009495:titanium dioxide; D014025:Titanium
Biosensor; Direct electrochemistry; Long-term stability; MXene; TiO(2)