Cancer metastasis is the leading cause of death in cancer patients worldwide and one of the major challenges in treating cancer.Circulating tumor cells(CTCs)play a pivotal role in cancer metastasis.However,the content...Cancer metastasis is the leading cause of death in cancer patients worldwide and one of the major challenges in treating cancer.Circulating tumor cells(CTCs)play a pivotal role in cancer metastasis.However,the content of CTCs in peripheral blood is minimal,so the detection of CTCs in real samples is extremely challenging.Therefore,efficient enrichment and early detection of CTCs are essential to achieve timely diagnosis of diseases.In this work,we constructed an innovative and sensitive single-nanoparticle collision electrochemistry(SNCE)biosensor for the detection of MCF-7 cells(human breast cancer cells)by immunomagnetic separation technique and liposome signal amplification strategy.Liposomes embedded with platinum nanoparticles(Pt NPs)were used as signal probes,and homemade gold ultramicroelectrodes(Au UME)were used as the working electrodes.The effective collision between Pt NPs and UME would produce distinguishable step-type current.MCF-7 cells were accurately quantified according to the relationship between cell concentration and collision frequency(the number of step-type currents generated per unit time),realizing highly sensitive and specific detection of MCF-7 cells.The SNCE biosensor has a linear range of 10 cells·mL^(-1)to 10^(5) cells·mL^(-1)with a detection limit as low as 5 cells·mL^(-1).In addition,the successful detection of MCF-7 cells in complex samples showed that the SNCE biosensors have great potential for patient sample detection.展开更多
Single-entity collisional electrochemistry(SECE)is a branch of single-entity electrochemistry.It can directly characterize entities/particles with single particle resolution through random collisions between particles...Single-entity collisional electrochemistry(SECE)is a branch of single-entity electrochemistry.It can directly characterize entities/particles with single particle resolution through random collisions between particles and electrodes in a solution,and obtain rich physicochemical information,thus becoming one of the frontiers of electroanalytical chemistry in the past two decades.Interestingly,the(micro/nanoscale)sensing electrodes have evolved from a polarizable liquid/liquid(mercury/liquid)interface to a solid/liquid interface and then to a liquid/liquid interface(i.e.,an interface between twoimmiscible electrolyte solutions,ITIES),as if they have completed a cycle(but in fact they have not).ITIES has become the latest sensing electrode in the booming SECE due to its polarizability(up to 1.1 V at the water/a,a,a-trifluorotoluene interface)and high reproducibility.The four measurement modes(direct electrolysis,mediated electrolysis,current blockade,and charge displacement)developed in the realm of SECE at solid/liquid interfaces have also been fully realized at the miniature ITIES.This article will discuss these four modes at the ITIES from the perspectives of basic concepts,operating mechanisms,and latest developments(e.g.,discovery of ionosomes,blockade effect of Faradaic ion transfer,etc.),and look forward to the future development and direction of this emerging field.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22274037,22376055 and 21904032)the Natural Science Foundation of Hubei Province(2022CFB383)。
文摘Cancer metastasis is the leading cause of death in cancer patients worldwide and one of the major challenges in treating cancer.Circulating tumor cells(CTCs)play a pivotal role in cancer metastasis.However,the content of CTCs in peripheral blood is minimal,so the detection of CTCs in real samples is extremely challenging.Therefore,efficient enrichment and early detection of CTCs are essential to achieve timely diagnosis of diseases.In this work,we constructed an innovative and sensitive single-nanoparticle collision electrochemistry(SNCE)biosensor for the detection of MCF-7 cells(human breast cancer cells)by immunomagnetic separation technique and liposome signal amplification strategy.Liposomes embedded with platinum nanoparticles(Pt NPs)were used as signal probes,and homemade gold ultramicroelectrodes(Au UME)were used as the working electrodes.The effective collision between Pt NPs and UME would produce distinguishable step-type current.MCF-7 cells were accurately quantified according to the relationship between cell concentration and collision frequency(the number of step-type currents generated per unit time),realizing highly sensitive and specific detection of MCF-7 cells.The SNCE biosensor has a linear range of 10 cells·mL^(-1)to 10^(5) cells·mL^(-1)with a detection limit as low as 5 cells·mL^(-1).In addition,the successful detection of MCF-7 cells in complex samples showed that the SNCE biosensors have great potential for patient sample detection.
基金supported by the National Natural Science Foundation of China(No.21904143).
文摘Single-entity collisional electrochemistry(SECE)is a branch of single-entity electrochemistry.It can directly characterize entities/particles with single particle resolution through random collisions between particles and electrodes in a solution,and obtain rich physicochemical information,thus becoming one of the frontiers of electroanalytical chemistry in the past two decades.Interestingly,the(micro/nanoscale)sensing electrodes have evolved from a polarizable liquid/liquid(mercury/liquid)interface to a solid/liquid interface and then to a liquid/liquid interface(i.e.,an interface between twoimmiscible electrolyte solutions,ITIES),as if they have completed a cycle(but in fact they have not).ITIES has become the latest sensing electrode in the booming SECE due to its polarizability(up to 1.1 V at the water/a,a,a-trifluorotoluene interface)and high reproducibility.The four measurement modes(direct electrolysis,mediated electrolysis,current blockade,and charge displacement)developed in the realm of SECE at solid/liquid interfaces have also been fully realized at the miniature ITIES.This article will discuss these four modes at the ITIES from the perspectives of basic concepts,operating mechanisms,and latest developments(e.g.,discovery of ionosomes,blockade effect of Faradaic ion transfer,etc.),and look forward to the future development and direction of this emerging field.
