In this study, an enzymatic electrode for glucose biosensing and bioanode of glucose/air biofuel cell has been fabricated by immobilizing poly (methylene green) (polyMG) for electrocatalytic NADH oxidation and NAD+-de...In this study, an enzymatic electrode for glucose biosensing and bioanode of glucose/air biofuel cell has been fabricated by immobilizing poly (methylene green) (polyMG) for electrocatalytic NADH oxidation and NAD+-dependent glucose dehydrogenase (GDH) for oxidizing glucose on carbon nanodots (CNDs). The polyMG-CNDscomposites obtained by electro-polymerization of dye MG molecules adsorbed on CNDs display excellent electrocatalytic activity toward NADH electro-oxidation at a low overpotential of ca. -0.10 V (vs. Ag/AgCl) and the integrated enzymatic electrode shows fast response to glucose electrooxidation. Using the fabricated GDH-based enzymatic electrode, a glucose biosensor was constructed and exhibits a wide linear dynamic range from 0 to 8 mM, a low detection limit of 0.02 μM (S/N = 3), and fast response time (ca. 4 s) under the optimized conditions. The developed glucose biosensor was used to detect glucose content in human blood with satisfactory results. The fabricated GDH-based enzymatic electrode was also employed as bioanode to assembly a glucose/air biofuel cell with the laccase-CNDs/GC as the biocathode. The maximum power density delivered by the assembled glucose/air biofuel cell reaches 3.1 μW·cm-2 at a cell voltage of 0.22 V in real sample fruit juice. The present study demonstrates that potential applications of GDH-based CNDs electrode in analytical and biomedical measurements.展开更多
It is highly desired to accurately and selectively detect and image intracellular L-lysine and pH in biological systems because they could act as the biomarkers in certain abnormal conditions and may give us a warning...It is highly desired to accurately and selectively detect and image intracellular L-lysine and pH in biological systems because they could act as the biomarkers in certain abnormal conditions and may give us a warning of the occurrence of diseases.It has been attracted more focuses to design new ratiometric fluorescent probe for monitoring L-lysine and pH to improve detection accuracy.Carbonized polymer dots(CPDs),which possess carbon/polymer hybrid structure rather than pure carbon structure and constitute of a carbon core and large amounts of functional groups/polymer chains on the surface,rise up as a new type of fluorescent nanomaterials and especially display many advantages for bioanalysis.In this study,o-phenylenediamine(o-PD)and poly(styrene-co-maleic anhydride)(PSMA)are used as the precursors to synthesize the desired CPDs through one-step hydrothermal amide method.The prepared CPDs display two well-resolved fluorescence emission bands,i.e.,a very weak emission centered at 470 nm in blue region and a strong emission centered at 558 nm in yellow region.It is found that the two emissions are both responsive to L-lysine based on the surface passivation mechanism,whereas,only the yellow emission is responsive to pH due to the protonation/deprotonation process of the amino groups.Based on the different responsive behaviors,ratiometric detection and imaging of L-lysine and pH are achieved.The prepared ratiometric CPDs probe is successfully applied for L-lysine and pH sensing and imaging at two emission channels in live cell and zebrafish with satisfactory results.展开更多
Multiple hydrogen bonds containing nucleophilic phosphines derived from dipeptide dual-reagents catalyzed asymmetric Michael addition reactions between indene esters and activated olefins in high yields and good to ex...Multiple hydrogen bonds containing nucleophilic phosphines derived from dipeptide dual-reagents catalyzed asymmetric Michael addition reactions between indene esters and activated olefins in high yields and good to excellent enantioselectivities under mild reaction conditions.The success of current highly selective reactions should provide inspiration for expansion to other reactions and would open up new paradigms for the synthesis of indanone derivatives bearing chiral quaternary carbon centers.展开更多
Reaction of sulfonylated binaphthol [2-hydroxy-2'-tosyloxy-l,l-binaphthyl (la, Ts-Binol) or 2-hydroxy-2'- (phenylsulfonyloxy)-l,l-binaphthyl (lb, Ps-Binol)] with 1 equiv, of ZnEt2 afforded zinc complexes [(Ys...Reaction of sulfonylated binaphthol [2-hydroxy-2'-tosyloxy-l,l-binaphthyl (la, Ts-Binol) or 2-hydroxy-2'- (phenylsulfonyloxy)-l,l-binaphthyl (lb, Ps-Binol)] with 1 equiv, of ZnEt2 afforded zinc complexes [(Ys-Binol)ZnEt]2 (2a) and [(Ps-Binol)ZnEt]2 (2b). Further reaction of zinc complexes 2a and 2b with benzyl alco- hol (BnOH) gave the zinc benzyloxide [(Ts-Binol)2Zn2(OBn)2]2 (3a) and [(Ps-Binol)2Znz(OBn)2]2 (3b). Alterna- tively, the zinc benzyloxides 3a and 3b could also be obtained by reaction of compound la or lb with Zn(OBn)2 (in situ reaction of ZnEt2 and BnOH). The complexes were fully characterized by elemental analyses and spectroscopic analyses, and complexes 2a, 2b and 3a were further characterized by single-crystal X-ray analyses. The catalytic activities of these zinc complexes towards ring-opening polymerization of ε-caprolactone and D,L-lactide were studied.展开更多
文摘In this study, an enzymatic electrode for glucose biosensing and bioanode of glucose/air biofuel cell has been fabricated by immobilizing poly (methylene green) (polyMG) for electrocatalytic NADH oxidation and NAD+-dependent glucose dehydrogenase (GDH) for oxidizing glucose on carbon nanodots (CNDs). The polyMG-CNDscomposites obtained by electro-polymerization of dye MG molecules adsorbed on CNDs display excellent electrocatalytic activity toward NADH electro-oxidation at a low overpotential of ca. -0.10 V (vs. Ag/AgCl) and the integrated enzymatic electrode shows fast response to glucose electrooxidation. Using the fabricated GDH-based enzymatic electrode, a glucose biosensor was constructed and exhibits a wide linear dynamic range from 0 to 8 mM, a low detection limit of 0.02 μM (S/N = 3), and fast response time (ca. 4 s) under the optimized conditions. The developed glucose biosensor was used to detect glucose content in human blood with satisfactory results. The fabricated GDH-based enzymatic electrode was also employed as bioanode to assembly a glucose/air biofuel cell with the laccase-CNDs/GC as the biocathode. The maximum power density delivered by the assembled glucose/air biofuel cell reaches 3.1 μW·cm-2 at a cell voltage of 0.22 V in real sample fruit juice. The present study demonstrates that potential applications of GDH-based CNDs electrode in analytical and biomedical measurements.
基金financially supported by the National Natural Science Foundation of China(Nos.21874001,21575004)the Foundation for Innovation Team of Bioanalytical Chemistry of Anhui Province。
文摘It is highly desired to accurately and selectively detect and image intracellular L-lysine and pH in biological systems because they could act as the biomarkers in certain abnormal conditions and may give us a warning of the occurrence of diseases.It has been attracted more focuses to design new ratiometric fluorescent probe for monitoring L-lysine and pH to improve detection accuracy.Carbonized polymer dots(CPDs),which possess carbon/polymer hybrid structure rather than pure carbon structure and constitute of a carbon core and large amounts of functional groups/polymer chains on the surface,rise up as a new type of fluorescent nanomaterials and especially display many advantages for bioanalysis.In this study,o-phenylenediamine(o-PD)and poly(styrene-co-maleic anhydride)(PSMA)are used as the precursors to synthesize the desired CPDs through one-step hydrothermal amide method.The prepared CPDs display two well-resolved fluorescence emission bands,i.e.,a very weak emission centered at 470 nm in blue region and a strong emission centered at 558 nm in yellow region.It is found that the two emissions are both responsive to L-lysine based on the surface passivation mechanism,whereas,only the yellow emission is responsive to pH due to the protonation/deprotonation process of the amino groups.Based on the different responsive behaviors,ratiometric detection and imaging of L-lysine and pH are achieved.The prepared ratiometric CPDs probe is successfully applied for L-lysine and pH sensing and imaging at two emission channels in live cell and zebrafish with satisfactory results.
基金The work was supported by the National Natural Science Foundation of China (21172004, 21172003 and 21072004), the National Basic Research Program of China (2012CB821604), and grants from the Ministry of Education (20103424110001).
基金Financial support from Chinese Academy of Sciences (No.XDB 20020100)the National Natural Science Foundation of China (Nos.21572247,21871282) is gratefully acknowledged。
文摘Multiple hydrogen bonds containing nucleophilic phosphines derived from dipeptide dual-reagents catalyzed asymmetric Michael addition reactions between indene esters and activated olefins in high yields and good to excellent enantioselectivities under mild reaction conditions.The success of current highly selective reactions should provide inspiration for expansion to other reactions and would open up new paradigms for the synthesis of indanone derivatives bearing chiral quaternary carbon centers.
文摘Reaction of sulfonylated binaphthol [2-hydroxy-2'-tosyloxy-l,l-binaphthyl (la, Ts-Binol) or 2-hydroxy-2'- (phenylsulfonyloxy)-l,l-binaphthyl (lb, Ps-Binol)] with 1 equiv, of ZnEt2 afforded zinc complexes [(Ys-Binol)ZnEt]2 (2a) and [(Ps-Binol)ZnEt]2 (2b). Further reaction of zinc complexes 2a and 2b with benzyl alco- hol (BnOH) gave the zinc benzyloxide [(Ts-Binol)2Zn2(OBn)2]2 (3a) and [(Ps-Binol)2Znz(OBn)2]2 (3b). Alterna- tively, the zinc benzyloxides 3a and 3b could also be obtained by reaction of compound la or lb with Zn(OBn)2 (in situ reaction of ZnEt2 and BnOH). The complexes were fully characterized by elemental analyses and spectroscopic analyses, and complexes 2a, 2b and 3a were further characterized by single-crystal X-ray analyses. The catalytic activities of these zinc complexes towards ring-opening polymerization of ε-caprolactone and D,L-lactide were studied.