Electrochemical detection of individual molecular tags in nanochannels may enable cost-effective, massively parallel analysis and diagnostics platforms. Here we demonstrate single-molecule detection of prototypical analytes in aqueous solution based on redox cycling in 40 nm nanogap transducers. These nanofluidic devices are fabricated using standard microfabrication techniques combined with a self-aligned approach that minimizes gap size and dead volume. We demonstrate the detection of three common redox mediators at physiological salt concentrations.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/nn404440v | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Unlocking new possibility of FeO@C@Ag nanostructures as an advanced SERS substrate for ultrasensitive detection of low-cross-section urea biomolecules.
RSC Adv
January 2025
Phenikaa University Nano Institute (PHENA), Phenikaa University Hanoi 12116 Vietnam
Surface-enhanced Raman spectroscopy (SERS) is widely recognized as a powerful analytical technique, offering molecular identification by amplifying characteristic vibrational signals, even at the single-molecule level. While SERS has been successfully applied for a wide range of targets including pesticides, dyes, bacteria, and pharmaceuticals, it has struggled with the detection of molecules with inherently low Raman scattering cross-sections. Urea, a key nitrogen-containing biomolecule and the diamide of carbonic acid, is a prime example of such a challenging target.
View Article and Find Full Text PDFSingle-Molecule Oxidoreductase Activity Analysis for Activity-Based Diagnosis Based on Proteoform Alterations.
J Am Chem Soc
January 2025
Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
We developed a single-molecule enzyme activity assay platform for NAD(P)-dependent oxidoreductases, leveraging a new NAD(P)H-responsive fluorogenic probe optimized for microdevice-based fluorometric detection. This platform enabled the detection of enzyme activities in blood and cerebrospinal fluid (CSF), including lactate dehydrogenase, glucose-6-phosphate dehydrogenase, and hexokinases. We demonstrate its potential for activity-based diagnosis by detecting altered populations of enzyme activity species in blood and CSF from liver damage in brain tumor patients.
View Article and Find Full Text PDFInsights into proliferative glomerulonephritis with monoclonal immunoglobulin deposits - is it really monoclonal or not?
Curr Opin Nephrol Hypertens
January 2025
Control of the immune response B and lymphoproliferation, CNRS UMR 7276, INSERM UMR 1262, University of Limoges, Centre de référence de l'amylose AL et autres maladies par dépôts d'immunoglobuline monoclonale, Limoges, France; Service de néphrologie et Centre National de référence amylose AL et autres maladies à dépôts d'immunoglobulines monoclonales, Centre Hospitalier Universitaire, Université de Poitiers, Poitiers, France.
Purpose Of Review: Proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID), is a disease defined by the presence of glomerulonephritis with nonorganized mono-isotypic immunoglobulin (Ig) deposits. This review will discuss the pathogenesis of PGNMID and address novel techniques for detection of monoclonal Ig and pathologic B-cell clones and for distinguishing monoclonal from oligoclonal Ig deposits.
Recent Findings: Because of low detection rate of circulating monoclonal Ig and nephritogenic B-cell clones and emerging reports of PGNMID-IgG in children, it has been recently argued that many PGNMID-IgG3 cases may not be monoclonal lesions.
Towards effective functionalization of nanopores/nanochannels: the role of amidation reactions.
Chem Commun (Camb)
January 2025
State Key Laboratory of Biogeology and Environmental Geology, Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China.
In recent years, researchers have drawn inspiration from natural ion channels to develop various artificial nanopores/nanochannels, including solid-state and biological. Through imitating the precise selectivity and single molecule sensing exhibited by natural ion channels, nanopores/nanochannels have been widely used in many fields, such as analyte detection, gene sequencing and so on. In these applications, the surface functionalization of nanopores/nanochannels directly determines the effectiveness in quantitative analysis and single molecule detection.
View Article and Find Full Text PDFClearance of beta-amyloid and tau aggregates is size dependent and altered by an inflammatory challenge.
Brain Commun
December 2024
Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.
Extracellular beta-amyloid aggregation and inflammation are in a complex and not fully understood interplay during hyperphosphorylated tau aggregation and pathogenesis of Alzheimer's disease. Our group has previously shown that an immune challenge with tumour necrosis factor alpha can alter extracellular beta-sheet containing aggregates in human-induced pluripotent stem cell-derived cortical neurons carrying familial Alzheimer's disease-related presenilin 1 mutations. Here, using single-molecule detection and super-resolution imaging techniques, we quantified and characterized the intra- and extracellular beta-amyloid and AT8-positive tau aggregates.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!