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1.
Biosens Bioelectron ; 195: 113671, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624798

RESUMO

The extracellular matrix (ECM) of tumor mediates malignant transformation and distant metastasis with extracellular proteinases, especially the matrix metalloproteinases (MMPs). However, there is no assay method to trace the dynamic content of MMPs in ECM. In this work, we have proposed a strategy by assembling peptide scaffold on ionic nanochannels to monitor the target proteinases. The short peptide unit is designed to induce self-assembly with good stability, biocompatibility and programmability, while ion nanochannels can provide electrochemical response upon the MMP activities. Taking MMP-2 as an example, the peptide unit includes two regions, one for self-assembly and one for bio-recognition, so the assembly region (KLVFF) can self-assemble to nanofiber networks. In the meantime, since the reactive region (PLGVR) has MMP-2 recognition site, the peptide assembly on nanochannel can thus be used for the detection of active MMP-2 in tumor microenvironment, with a wide linear detection range (10 fg/mL-10 ng/mL) and 6.6 fg/mL limit of detection. Moreover, the availability of the established ECM mimic is able to distinguish active MMP-2 from latent proMMP-2 in tumor samples. By designing different peptide units for self-assembly on the ionic nanochannel, the assay platform can be promisingly used for other proteinases in ECM, so this work may provide a useful approach to trace the dynamic content of the MMPs in tumor microenvironment (TEM).

2.
Small ; : e2103255, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34605143

RESUMO

CsPbX3 perovskite nanocrystals (NCs), with excellent optical properties, have drawn considerable attention in recent years. However, they also suffer from inherent vulnerability and hydrolysis, causing the new understanding or new applications to be difficultly explored. Herein, for the first time, it is discovered that the phospholipid membrane (PM)-coated CsPbX3 NCs have intrinsic biocatalytic activity. Different from other peroxidase-like nanozymes relying on extra chromogenic reagents, the PM-CsPbX3 NCs can be used as a self-reporting nanoprobe, allowing an "add-to-answer" detection model. Notably, the fluorescence of PM-CsPbX3 NCs can be rapidly quenched by adding H2 O2 and then be restored by removing excess H2 O2 . Initiated from this unexpected observation, the PM-CsPbX3 NCs can be explored to prepare multi-color bioinks and metabolite-responsive paper analytical devices, demonstrating the great potential of CsPbX3 NCs in bioanalysis. This is the first report on the discovery of nanozyme-like property of all-inorganic CsPbX3 perovskite NCs, which adds another piece to the nanozyme puzzle and opens new avenues for in vitro disease diagnostics.

3.
Biosens Bioelectron ; 195: 113667, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34598107

RESUMO

Measurement of signal molecule is critically important for understanding living systems. Nitric oxide (NO) is a key redox signal molecule that shows diverse roles in virtually all life forms. However, probing into NO's activities is challenging as NO has restricted lifetime (<10 s) and limited diffusion distance (usually <200 µm). So, for the direct acupuncture of NO within the time-space resolution, an electrochemical microsensor has been designed and fabricated in this work. Fabrication of the microsensor is achieved by (1) selective assembly of an electrocatalytic transducer, (2) attaching the transducer on carbon fiber electrode, and (3) covered it with a screen layer to reduce signal interference. The fabricated microsensor exhibits high sensitivity (LOD, 13.5 pM), wide detection range (100 pM-5 µM), and good selectivity. Moreover, studies have revealed that the availability of the sensor for efficient detection of NO is due to the formation of a specific DNA/porphyrin hybrid structure that has synergetic effects on NO electrocatalysis. Therefore, NO release by cells and tissues can be directly and precisely traced, in which we have obtained the release pattern of NO by different cancer cell lines, and have known its dynamics in tumor microenvironment. The fabricated electrocatalytic microsensor may provide a unique and useful tool for the direct assay of NO with high time-space resolution, which promisingly gives a technical solution for the bioassay of NO in living systems.

4.
Anal Chem ; 93(39): 13382-13388, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34549940

RESUMO

To improve long-term graft patient outcomes and develop more effective antirejection therapies, noninvasive monitoring of acute cellular rejection (ACR) after organ transplantation is urgently needed. As a biomarker of ACR, Granzyme B (GrB) is expected to be applied in the noninvasive monitoring of ACR. Herein, we have developed a method for detecting the GrB activity based on the target-initiated great change in electrochemical steric hindrance by designing a nanoprobe. The nanoprobe is prepared by conjugating a specific peptide, which is responsive to GrB cleavage activity, to gold nanoparticles (AuNPs). Meanwhile, a piece of DNA sequence with G-quadruplex (G4) is attached at the distal end of the peptide. Upon exposure to GrB, the peptide substrate is cleaved to eliminate the steric hindrance between inter-nanoprobes as well as nanoprobe and DNA tetrahedron (TDN), allowing the released DNA strand to hybridize with TDN, giving sensitive signal output. The method can also be used to detect GrB activity in complex biological settings, so it has a great potential for monitoring GrB activity in the blood or urine of graft patients.


Assuntos
Ouro , Rejeição de Enxerto/diagnóstico , Nanopartículas Metálicas , Transplante de Órgãos , Granzimas , Humanos
5.
J Am Chem Soc ; 143(39): 16078-16086, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34495654

RESUMO

Breast cancer is one of the most common malignant diseases among women worldwide, and the existence of breast cancer stem cells is closely associated with poor outcomes. Herein, we report an electrochemical phenotyping method to characterize the stemlike phenotype in breast cancer, offering a low-cost but robust choice other than the highly expensive and experience-dependent flow cytometry. Specially, after immune-magnetic beads-assisted enrichment, an in situ programmable DNA circuit is designed using capture probes to bring in the toeholds for DNA assembly and effector probes to accelerate the removal of background signals. The electrochemical phenotyping method could sensitively determine breast cancer stem cells in a wide linear range and exhibit desirable accuracy and reliability. The method can not only monitor the phenotypic transition of breast cancer cells and the drug-reversed effect but also determinate stemlike phenotype in the mice bearing breast cancer xenograft tumor. Overall, the electrochemical phenotyping method may provide promising technical support for precise management of breast tumors.

6.
Front Med ; 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34570311

RESUMO

Cancer imposes a severe threat to people's health and lives, thus pressing a huge medical and economic burden on individuals and communities. Therefore, early diagnosis of cancer is indispensable in the timely prevention and effective treatment for patients. Exosome has recently become an attractive cancer biomarker in noninvasive early diagnosis because of the unique physiology and pathology functions, which reflects remarkable information regarding the cancer microenvironment, and plays an important role in the occurrence and evolution of cancer. Meanwhile, biosensors have gained great attention for the detection of exosomes due to their superior properties, such as convenient operation, real-time readout, high sensitivity, and remarkable specificity, suggesting promising biomedical applications in the early diagnosis of cancer. In this review, the latest advances of biosensors regarding the assay of exosomes were summarized, and the superiorities of exosomes as markers for the early diagnosis of cancer were evaluated. Moreover, the recent challenges and further opportunities of developing effective biosensors for the early diagnosis of cancer were discussed.

7.
Anal Chem ; 93(32): 11159-11166, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34347435

RESUMO

Phenotypic plasticity is an emerging paradigm for providing biological and clinical insights into cancer initiation, progression, and resistance to therapy. However, it is a great challenge to track phenotypic information on live cells with high levels of sensitivity, specificity, and simplicity, when a specific cancer-cell subset is being targeted. In this work, we have successfully achieved cascade assembly of nanoparticles on the surface of specific cancer cells by designing a dual-aptamer-weaved molecular AND logic system. Taking advantage of spatial addressability, precise controllability, and targeting recognition of the nanostructure assemblies, we can precisely label the target-cell subset in a large population of similar cells and rapidly obtain phenotypic information in response to the surface changes of captured cancer cells. Without sophisticated instruments, we can know the phenotypic information on HepG2 cells in whole blood with a high level of sensitivity and rapid naked-eye tracking of on-cell phenotype changes of HepG2 cells undergoing epithelial-mesenchymal transition.


Assuntos
Aptâmeros de Nucleotídeos , Nanoestruturas , Tecnologia de Rastreamento Ocular , Células Hep G2 , Humanos , Fenótipo
8.
ACS Appl Mater Interfaces ; 13(33): 39719-39729, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34392680

RESUMO

In this work, cucurbiturils (CBs), a class of macrocyclic supramolecules, were observed to have an interesting peroxidase-like activity, which is metal-free, substrate-specific, thermophilic, acidophilic, and insensitive to ionic strength. By coating CBs on enzyme-encapsulated zeolitic imidazolate framework-8 (ZIF-8), a composite nanozyme was constructed, which retains the catalytic ability of CBs and enzymes and makes them cascade. On addition of the substrate, i.e., the detection target, a highly efficient cascade catalysis can be launched in all the spatial directions to generate sensitive and visible signals. Convenient detection of glucose and cholesterol as models is thereby achieved. More importantly, we have also successfully constructed a composite nanozyme-based sensor array (6 × 8 wells) and thereby achieved simultaneous colorimetric analysis of multiple samples. The concept and successful practice of the construction of the unique core-shell supramolecule/biomolecule@nanomaterial architecture provide the possibility to fabricate next-generation multifunctional materials and create new applications by integrating their unique functions.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Imidazóis/química , Nanocompostos/química , Peroxidases/química , Zeolitas/química , Técnicas Biossensoriais , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Catálise , Colorimetria , Corantes Fluorescentes/química , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Peróxido de Hidrogênio/química , Imidazóis/metabolismo , Simulação de Acoplamento Molecular , Oxirredução , Peroxidases/metabolismo , Impressão Tridimensional
9.
Chem Commun (Camb) ; 57(68): 8508-8511, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34351331

RESUMO

In this work, we have designed a template-free multiple signal amplification method for the highly sensitive detection of cancer cell-derived exosomes. In this design, DNase I serves as a bridge to link the DNA-based amplification approach and terminal deoxynucleotidyl transferase (TdT)-mediated polymerization reaction. Consequently, a detection limit of 10 particles per µL can be achieved, while a complex nucleic acid sequence design can be avoided. This method also exhibits good performance in a complicated matrix and enables the differentiation of healthy individuals from colorectal cancer (CRC) patients.


Assuntos
Técnicas Biossensoriais , Exossomos/química , Neoplasias/metabolismo , Anticorpos , Aptâmeros de Nucleotídeos , DNA/química , DNA/metabolismo , DNA Nucleotidilexotransferase/metabolismo , Desoxirribonuclease I/metabolismo , Exossomos/metabolismo , Células HeLa , Humanos , Técnicas de Amplificação de Ácido Nucleico
10.
Biosens Bioelectron ; 191: 113465, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34218177

RESUMO

Exosomes are regarded as a promising biomarker in the diagnosis of disease due to their close relationship with the change of physiology and pathology. However, it is still a hard challenge to come up with a highly sensitive method for the exosomes detection. Herein, we propose a spherical nucleic acids (SNAs)-based cascade signal amplification strategy for the exosomes detection with high sensitivity. In this method, SNAs anchoring on exosomes membrane can be extended to form polyT sequence by terminal deoxynucleotidyl transferase (TdT), generating a template strand for the Exo III-catalyzed excision of the designed signal probe (probe A), which may finally induce significant decrease of electrochemical signal due to the consumption of probe A. Benefiting from the SNAs-based cascade signal amplification, this fabricated biosensor achieves a limit of detection for exosomes as low as 44 particles/µL. Moreover, this method shows good performance in the differentiation of healthy and malignancy colorectal cancer patients. Therefore, without complicated nucleic acids sequences design, our approach provides a cascade signal amplification strategy for the highly sensitive detection of exosomes and shows the potential applications in clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Exossomos , Ácidos Nucleicos , DNA Nucleotidilexotransferase , Exossomos/genética , Humanos , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico
11.
ACS Appl Mater Interfaces ; 13(31): 36919-36925, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34328724

RESUMO

The structures assembled by peptides have attracted great attention due to their unique physicochemical properties. Moreover, the co-assembly of peptides with additional components can endow the structures with extended functions. In this work, we have explored the co-assembly of peptides and carbon nanodots (CNDs) by taking advantage of their non-covalent binding; thus, the obtained structure may show both the recognition capability of peptides and the catalytic activity of CNDs. Therefore, we have further used the assembled structure for the sensitive analysis of transglutaminase 2 with a low detection limit of 0.25 pg/mL. By simply replacing the peptide sequences or the nanomaterials, the strategy proposed in this work can be developed as a universal model to build the co-assemblies of peptides and nanomaterials, thus leading to their broader applications in biological and biomedical research.

12.
Chem Commun (Camb) ; 57(53): 6522-6525, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34105555

RESUMO

We have proposed a simple electrochemical method in this work for the assay of tumor cells through their own steric hindrance effect. Specifically, tumor cells can block the catalysis of terminal deoxynucleotidyl transferase to the aptamer previously immobilized on the electrode surface. By making use of the hindrance effect, cancer cells can be quantitatively analyzed in the range from 1.6 × 102 to 1.6 × 106 cells per mL without complicated design or cumbersome operation, while the detection limit can be about 53 cells per mL. This method can also show satisfactory performance in complex environments, indicating its potential in clinical application.


Assuntos
Separação Celular/métodos , Eletroquímica/métodos , Linhagem Celular Tumoral , Eletrodos , Humanos , Limite de Detecção
13.
J Mater Chem B ; 9(27): 5451-5455, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34184004

RESUMO

Metal-organic frameworks (MOFs) are proposed to protect a CRISPR-associated enzyme/RNA complex from harsh environments, while the complex can be quickly released from MOFs with high efficiency. Therefore, the application of CRISPR-powered biosensing can be more feasible.

14.
Anal Chem ; 93(25): 8994-9001, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34151551

RESUMO

Metal-organic framework (MOF) thin films with flexible nature and prominent qualities have opened doors to new technological applications in different fields. Herein, we propose an electrochemical biosensor for the dual detection of Staphylococcus aureus based on the electrodeposition of Cu metal-organic framework (Cu-MOF) thin films. The promising sensing layer with features of good electronic conductivity and enhanced electron-transfer property can not only identify S. aureus through specific micrococcal nucleases in the supernatant but also detect the pathogen directly via aptamer recognition. The dual analysis design ensures the accuracy of this method for S. aureus detection in the range of 7-7 × 106 cfu/mL with the limits of detection of 1.9 and 5.2 cfu/mL. Moreover, the analytical method validation confirmed that the biosensor could efficiently work in complex biological samples, showing good selectivity and specificity and great potential for clinical diagnosis. More importantly, the current proposed strategy is simple and easy to implement without the need for extra signaling elements, which is convenient for timely clinical detection.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Infecções Estafilocócicas , Humanos , Limite de Detecção , Staphylococcus aureus
15.
Biosens Bioelectron ; 186: 113309, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33984795

RESUMO

The pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is continuously worsening globally, herein we have proposed an electrochemical biosensor for the sensitive monitoring of SARS-CoV-2 RNA. The presence of target RNA firstly triggers the catalytic hairpin assembly circuit and then initiates terminal deoxynucleotidyl transferase-mediated DNA polymerization. Consequently, a large number of long single-stranded DNA products can be produced, and these negatively charged DNA products will bind a massive of positively charged electroactive molecular of Ru(NH3)63+ due to the electrostatic adsorption. Therefore, significantly amplified electrochemical signals can be generated for sensitive analysis of SARS-CoV-2 RNA in the range of 0.1-1000 pM with the detection limit as low as 26 fM. Besides the excellent distinguishing ability for SARS-CoV-2 RNA against single-base mismatched RNA, the proposed biosensor can also be successfully applied to complex matrices, as well as clinical patient samples with high stability, which shows great prospects of clinical application.

16.
ACS Appl Mater Interfaces ; 13(15): 17268-17275, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33834755

RESUMO

Efficiently assessing the invasive capability of tumor cells is critical both for the research and treatment of cancer. Here, we report a novel method called the electrochemical trans-channel assay for efficient evaluation of tumor cell invasiveness. A bioinspired extracellular matrix degradation model (EDM) has been first fabricated on a porous anodic alumina (PAA) membrane to construct the electrochemical apparatus. Upon contacting the invasive tumor cells, invasive capability can be sensitively evaluated by the degree of EDM impairment, which is recorded by the electrochemical trans-channel ionic currents in a label-free manner. Compared to the most commonly used trans-well migration method, this assay can be accomplished in an efficient way that is significantly faster (20 min) and more convenient. Besides, quantitation can also be realized for monitoring the invasion process, which cannot be achieved by other currently used methods. Our proposed electrochemical trans-channel assay method has shown a synergistic effect for the evaluation of tumor cell invasiveness, providing a promising method for clinical assessment or prognostic applications of tumor metastasis.


Assuntos
Biomimética/instrumentação , Invasividade Neoplásica , Óxido de Alumínio/química , Eletroquímica , Eletrodos , Membranas Artificiais , Porosidade , Fatores de Tempo
17.
Anal Chem ; 92(22): 15162-15168, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33155796

RESUMO

Biomimetic construction of artificial scaffolds has attracted increasing attention. However, the construction methods usually require redundant materials and procedures, which is inconvenient for further application. Herein, inspired by the polyvalent multifunctional structure in nature, we have designed a polyvalent biotinylated aptamer scaffold (PBAS) which can conduct analytical performance with high sensitivity and simplified procedures. To construct a PBAS, the aptamers are designed to hybridize with prepared linker probes to form polyvalent biotinylated scaffolds, which contain both multiple aptamers and signal labels. Therefore, multifunctional scaffolds can be constructed with high recognition and capture efficiency as well as significant signal amplification. Furthermore, the scaffold can be used for the assay of some disease marker proteins. By taking tau proteins as an example, the proposed aptasensor can exhibit excellent performance with a low detection limit of 153 pg mL-1 and a short assay time of 50 min, which is much better than most of the previous methods. By assays of tau proteins in both serum and artificial cerebro spinal fluid, the PBAS-based aptasensor can work well. Therefore, the scaffold may be expected to be a powerful analytical tool which may have wide applications in the detection of a variety of analytes.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Técnicas Biossensoriais/métodos , Limite de Detecção , Proteínas tau/metabolismo , Biotinilação , Humanos , Fatores de Tempo , Proteínas tau/sangue
18.
Chem Commun (Camb) ; 56(89): 13768-13771, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33084644

RESUMO

Exosomes have been widely considered as excellent noninvasive or minimally invasive biomarkers; however, the currently available methods for exosome detection usually need sophisticated instruments, or the sensitivity cannot be satisfactory, since the size of exosomes is very large. Nevertheless, in this work, by making use of the steric hindrance of exosomes due to their large size, we have developed a simple and sensitive method for the detection of exosomes with great potential in clinical use.


Assuntos
Técnicas Biossensoriais , Exossomos/química , Aptâmeros de Nucleotídeos/química , Células HeLa , Humanos , Espectrometria de Fluorescência
19.
Biosens Bioelectron ; 169: 112613, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956904

RESUMO

In this work, we have prepared peptide-functionalized metal-organic frameworks (MOFs) as signal-amplifying tags for the detection of secreted protein acidic and rich in cysteine (SPARC). Furthermore, enzyme-MOF nanocomposites are fabricated via a coprecipitation strategy between horse radish peroxidase (HRP) and ZIF-90, where ZIF-90 is used as a protective support for HRP immobilization. Meanwhile, the peptide sequence has been designed as SPARC-binding peptide, which imparts biorecognition functionality to HRP@ZIF-90 for performing a colorimetric sensor. Therefore, during the test, HRP molecules can be quickly released from nanocomposites by acidic condition to catalyze chromogenic reaction, enabling the ultrasensitive detection of SPARC with a low detection limit of 30 fg/mL. Moreover, the content of SPARC in colon cancer tissues with different degrees of differentiation can be determined with this sensor, demonstrating that the expression of SPARC is closely related to the occurrence, invasion and metastasis of human colon cancer. These results may show the potential applications of this biosensor in SPARC fundamental research as well as clinical diagnosis in the future.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Nanocompostos , Cisteína , Osteonectina , Peptídeos
20.
Biosens Bioelectron ; 169: 112638, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32987328

RESUMO

Covalent organic frameworks (COFs) have attracted more and more attention due to their diverse structures and multifunctionality. Their unique physicochemical properties make them exhibit great application potential in the field of biosensing. In this work, we have designed and fabricated a novel COFs-based nanoprobe named HRP-pSC4-AuNPs@COFs, where spherical COFs are functionalized with para-sulfocalix [4] arene hydrate (pSC4)-modified gold nanoparticles (AuNPs) and horseradish peroxidase (HRP). Then, we have applied it for the electrochemical detection of colorectal cancer (CRC)-derived exosomes. In this design, pSC4 as amicable linker can recognize and bind with various amino acid residues on the exosomes surface, while AuNPs with excellent conductivity can accelerate the migration of charge carriers and improve the response of biosensors. Noteworthy, the high porosity of COFs allows them to load a large amount of HRP, endowing COF with high catalytic activity. Meanwhile, the exoskeleton of COFs can maintain the functionality of HRP with significantly elevated stability. With such design, the proposed method shows excellent analytical performance for the detection of CRC-derived exosomes in the linear range from 5 × 102 to 107 particles/µL with a detection limit down to 160 particles/µL. Further, this method has also been used to analyze clinical serum sample, and can successfully distinguish CRC patients from healthy people, indicating the promising potential in clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Neoplasias Colorretais , Exossomos , Nanopartículas Metálicas , Estruturas Metalorgânicas , Neoplasias Colorretais/diagnóstico , Ouro , Humanos
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