Immobilization of Ni-Pd/core-shell nanoparticles through thermal polymerization of acrylamide on glassy carbon electrode for highly stable and sensitive glutamate detection.
The preparation of a persistently stable and sensitive biosensor is highly important for practical applications. To improve the stability and sensitivity of glutamate sensors, an electrode modified with glutamate dehydrogenase (GDH)/Ni-Pd/core-shell nanoparticles was developed using the thermal polymerization of acrylamide (AM) to immobilize the synthesized Ni-Pd/core-shell nanoparticles onto a glassy carbon electrode (GCE). The modified electrode was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). Electrochemical data showed that the prepared biosensor had remarkably enhanced electrocatalytic activity toward glutamate. Moreover, superior reproducibility and excellent stability were observed (relative average deviation was 2.96% after continuous use of the same sensor for 60 times, and current responses remained at 94.85% of the initial value after 60 d). The sensor also demonstrated highly sensitive amperometric detection of glutamate with a low limit of detection (0.052 μM, S/N = 3), high sensitivity (4.768 μA μM(-1) cm(-2)), and a wide, useful linear range (0.1-500 μM). No interference from potential interfering species such as l-cysteine, ascorbic acid, and l-aspartate were noted. The determination of glutamate levels in actual samples achieved good recovery percentages.
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China; School of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Nanning, 530008, China; School of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Nanning, 530008, China; Key Laboratory of Chemistry and Engineering of Forest Products, Guangxi University for Nationalities, Nanning, 530008, China; Key Laboratory of Guangxi Colleges and Universities for Food Safety and Pharmaceutical Analytical Chemistry, Guangxi University for Nationalities, Nanning, 530008, China. Electronic address: doyhc@126.com.
Huicheng
H
Yu
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China.
Zhenzhen
Z
Ma
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China. Electronic address: zywu@hnu.edu.cn.
Zhaoyang
Z
Wu
D020106:Acrylamide / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D004566:Electrodes; D005139:Eyeglasses; D018698:Glutamic Acid / Q000032:analysis*; D053768:Metal Nanoparticles / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*; D010316:Particle Size; D058105:Polymerization; D013499:Surface Properties; D013696:Temperature
D020106:Acrylamide; D018698:Glutamic Acid; D010165:Palladium; D002244:Carbon; D009532:Nickel
Biosensor; Core/shell nanoparticles; Glutamate; Glutamate dehydrogenase; Immobilization