Examination of performance of glassy carbon paste electrode modified with gold nanoparticle and xanthine oxidase for xanthine and hypoxanthine detection

Preparation of Magnetic Microsphere‐Gold Nanoparticle‐Immobilized Enzyme Batch Reactor and Its Application to Enzyme Inhibitor Screening in Natural Extracts by Capillary Electrophoresis

“…[23,24] Therefore, the enzyme batch reactor was prepared by the surface functionalization of MB-AuNPs with enzyme. Experimental conditions: 1 mL of 10 unit/mL XOD solution was activated with TCEP (10 mM) for 1 h, and then was added to 100 μL of MB-AuNPs solution.…”

Gold nanoparticle-based electrochemical biosensors

“…A reagentless glucose biosensor based on direct electron transfer of GOx [17], an HRP biosensor [18], and a Tyr biosensor for phenol detection [19] have been constructed by immobilizing the corresponding enzymes onto electrodes prepared by mixing colloidal gold with the carbon paste components. Based on a similar methodology, a composite electrode was also recently prepared by modifying glassy carbon microparticles with gold nanoparticles and xanthine oxidase for xanthine and hypoxanthine detection [20].…”

“…= 6.31%, 5 M X (n = 5), R.S.D. = 3.57% 80 M Hx (n = 5) Xanthine (X) hypoxanthine (Hx)/canned tuna fish Linear range: 5.0 × 10 −7 -1.0 × 10 −5 M (X); 5.0 × 10 −6 -1.5 × 10 −4 M (Hx); slope = 0.24 A M −1 (X); 0.14 A M −1 (Hx)[20] …”

Highly sensitive electrocatalytic biosensing of hypoxanthine based on functionalization of graphene sheets with water-soluble conducting graft copolymer

“…After the addition of hypoxanthine, the anodic current immediately increased and reached 95% of steadystate current within 5 s. The linear concentration range was from 3 × 10 −8 M to 2.8 × 10 −5 M with a correlation coefficient of 0.999, a high sensitivity of 673 ± 4 A M −1 cm −2 and a detection limit of 10 nM at the signal-to-noise ratio of 3. The performance of the biosensor was better than those of ruthenium purple-mediated biosensor with a linear range from 2 × 10 −7 M to 4 × 10 −5 M and a sensitivity of 334 A M −1 cm −2 (Tian et al, 2007), electrochemiluminescent biosensor with a linear range from 8.0 × 10 −6 M to 3.0 × 10 −4 M and a detection limit of 3 M (Lin et al, 2008), and gold nanoparticle-based amperometric biosensor with a linear range from 5.0 × 10 −6 to 1.5 × 10 −4 M (Cubukcu et al, 2007). To our best knowledge, this was the lowest detection limit of electrochemical biosensors for hypoxanthine.…”