TY - JOUR
T1 - Graphene quantum dots-based nanocomposite for electrocatalytic application of L-cysteine in whole blood and live cells
AU - Arul, P.
AU - Huang, Sheng Tung
AU - Mani, Veerappan
AU - Huang, Chih Hung
N1 - KAUST Repository Item: Exported on 2022-09-14
Acknowledgements: The authors are grateful for the financial support from the Ministry of Science and Technology, Taiwan (MOST-107–2113-M-027–006 and MOST-108–2113-M-027–001). P. Arul would like to gratitude National Taipei University of Technology for the position of Research Assistant Professor.
PY - 2022/8/8
Y1 - 2022/8/8
N2 - Driven by the urgent need to detect amino acids in live cells at trace levels, as they are an important biomarker for various diseases. For this purpose, we have developed a nanomolar level detection of L-cysteine (L-Cys) and real-time cellular quantification from live cells based on graphene quantum dots (GQDs)-AuNPs-metal-free organic framework (MFOF). Different analytical and microscopic techniques were used to confirm the synthesized nanocomposite. The sensitive electrochemical sensing system of L-Cys-was detected synergistically with GQDs-AuNPs-MFOF/GCE by voltammetry and amperometric i-t curve. The electrocatalytic oxidation signal of L-Cys-at Epa = none, +0.45, +0.36 and +0.21 V (vs. Ag/AgCl) with enhanced current responses were observed at control GCE, MFOF, GQDs-MFOF, and GQDs-AuNPs-MFOF/GCEs by DPV. The nanocomposite modified sensor probe showed a wide linear range concentration from 1 nM to 0.5 mM with LOD of 0.124 nM (S/N = 3), LOQ of 0.863 nM (S/N = 10) and sensitivity of 2.364 μA μM−1 cm−2. Subsequently, the selective detection of L-Cys-in the presence of possible other interfering biothiols. amino acids, and metal ions were achieved. The practical application was demonstrated in human whole blood and bio-fluid samples. Finally, the endogenous real-time detection of cellular cysteine in live cells was demonstrated.
AB - Driven by the urgent need to detect amino acids in live cells at trace levels, as they are an important biomarker for various diseases. For this purpose, we have developed a nanomolar level detection of L-cysteine (L-Cys) and real-time cellular quantification from live cells based on graphene quantum dots (GQDs)-AuNPs-metal-free organic framework (MFOF). Different analytical and microscopic techniques were used to confirm the synthesized nanocomposite. The sensitive electrochemical sensing system of L-Cys-was detected synergistically with GQDs-AuNPs-MFOF/GCE by voltammetry and amperometric i-t curve. The electrocatalytic oxidation signal of L-Cys-at Epa = none, +0.45, +0.36 and +0.21 V (vs. Ag/AgCl) with enhanced current responses were observed at control GCE, MFOF, GQDs-MFOF, and GQDs-AuNPs-MFOF/GCEs by DPV. The nanocomposite modified sensor probe showed a wide linear range concentration from 1 nM to 0.5 mM with LOD of 0.124 nM (S/N = 3), LOQ of 0.863 nM (S/N = 10) and sensitivity of 2.364 μA μM−1 cm−2. Subsequently, the selective detection of L-Cys-in the presence of possible other interfering biothiols. amino acids, and metal ions were achieved. The practical application was demonstrated in human whole blood and bio-fluid samples. Finally, the endogenous real-time detection of cellular cysteine in live cells was demonstrated.
UR - http://hdl.handle.net/10754/680448
UR - https://linkinghub.elsevier.com/retrieve/pii/S0013468622010945
UR - http://www.scopus.com/inward/record.url?scp=85135687215&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2022.140937
DO - 10.1016/j.electacta.2022.140937
M3 - Article
SN - 0013-4686
VL - 428
SP - 140937
JO - Electrochimica Acta
JF - Electrochimica Acta
ER -
