scholarly journals Metal-Enhanced Intrinsic Fluorescence of Proteins on Silver Nanostructured Surfaces toward Label-Free Detection

2008 ◽  
Vol 112 (46) ◽  
pp. 17957-17963 ◽  
Author(s):  
Krishanu Ray ◽  
Mustafa H. Chowdhury ◽  
Henryk Szmacinski ◽  
Joseph R. Lakowicz
Keyword(s):  
Intrinsic Fluorescence ◽  
Label Free ◽  
Nanostructured Surfaces ◽  
Label Free Detection

Intrinsic fluorescence–based label-free detection of bovine amyloid A amyloidosis

2021 ◽  
pp. 104063872110492
Author(s):  
Naoki Ujike ◽  
Susumu Iwaide ◽  
Yuki Ono ◽  
Takayuki Okano ◽  
Tomoaki Murakami
Keyword(s):  
Analytical Data ◽  
Principal Component ◽  
Histochemical Staining ◽  
Intrinsic Fluorescence ◽  
Label Free ◽  
Simple Method ◽  
Spectrometry Analysis ◽  
Amyloid A ◽  
Label Free Detection ◽  
Tissue Homogenates

Amyloidosis is diagnosed by the histologic detection of amyloid deposits; however, this method has limitations such as a prolonged diagnosis time and the need for histologic proficiency. We aimed to develop a rapid and simple method for diagnosing amyloidosis by targeting amyloid-specific endogenous fluorescence, which has not been reported previously, to our knowledge. Fluorescence fingerprint analysis of amyloid extracts and tissue homogenates derived from amyloid A (AA) amyloidosis-affected cattle exhibited a specific intrinsic fluorescence pattern. Furthermore, principal component analysis using analytical data revealed that AA could be identified by peaks near λex 350 nm and λem 430 nm. Fluorescence spectrometry analysis using tissue homogenates, which does not require special histochemical staining, enables the rapid detection of bovine AA.

scholarly journals The Role of Surface Chemistry in the Efficacy of Protein and DNA Microarrays for Label-Free Detection: An Overview

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1026
Author(s):  
Elisa Chiodi ◽  
Allison M. Marn ◽  
Matthew T. Geib ◽  
M. Selim Ünlü
Keyword(s):  
Surface Chemistry ◽  
Surface Functionalization ◽  
Dna Microarrays ◽  
Label Free ◽  
Polymeric Coatings ◽  
Label Free Detection ◽  
Particle Imaging ◽  
Single Particle Imaging ◽  
The Impact

The importance of microarrays in diagnostics and medicine has drastically increased in the last few years. Nevertheless, the efficiency of a microarray-based assay intrinsically depends on the density and functionality of the biorecognition elements immobilized onto each sensor spot. Recently, researchers have put effort into developing new functionalization strategies and technologies which provide efficient immobilization and stability of any sort of molecule. Here, we present an overview of the most widely used methods of surface functionalization of microarray substrates, as well as the most recent advances in the field, and compare their performance in terms of optimal immobilization of the bioreceptor molecules. We focus on label-free microarrays and, in particular, we aim to describe the impact of surface chemistry on two types of microarray-based sensors: microarrays for single particle imaging and for label-free measurements of binding kinetics. Both protein and DNA microarrays are taken into consideration, and the effect of different polymeric coatings on the molecules’ functionalities is critically analyzed.

scholarly journals Label-Free Electrochemical Sensor for Rapid Bacterial Pathogen Detection Using Vancomycin-Modified Highly Branched Polymers

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1872
Author(s):  
Holger Schulze ◽  
Harry Wilson ◽  
Ines Cara ◽  
Steven Carter ◽  
Edward N. Dyson ◽  
...  
Keyword(s):  
Pathogen Detection ◽  
Electrochemical Impedance ◽  
Point Of Care ◽  
Branched Polymers ◽  
Label Free ◽  
Conformation Change ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
Staphylococcus Carnosus ◽  
Label Free Detection

Rapid point of care tests for bacterial infection diagnosis are of great importance to reduce the misuse of antibiotics and burden of antimicrobial resistance. Here, we have successfully combined a new class of non-biological binder molecules with electrochemical impedance spectroscopy (EIS)-based sensor detection for direct, label-free detection of Gram-positive bacteria making use of the specific coil-to-globule conformation change of the vancomycin-modified highly branched polymers immobilized on the surface of gold screen-printed electrodes upon binding to Gram-positive bacteria. Staphylococcus carnosus was detected after just 20 min incubation of the sample solution with the polymer-functionalized electrodes. The polymer conformation change was quantified with two simple 1 min EIS tests before and after incubation with the sample. Tests revealed a concentration dependent signal change within an OD600 range of Staphylococcus carnosus from 0.002 to 0.1 and a clear discrimination between Gram-positive Staphylococcus carnosus and Gram-negative Escherichia coli bacteria. This exhibits a clear advancement in terms of simplified test complexity compared to existing bacteria detection tests. In addition, the polymer-functionalized electrodes showed good storage and operational stability.

H2O2-sensitive quantum dots for the label-free detection of glucose

Talanta ◽  
2010 ◽  
Vol 82 (3) ◽  
pp. 997-1002 ◽  
Author(s):  
Mei Hu ◽  
Jing Tian ◽  
Hao-Ting Lu ◽  
Li-Xing Weng ◽  
Lian-Hui Wang
Keyword(s):  
Quantum Dots ◽  
Label Free ◽  
Label Free Detection

scholarly journals Affinity Sensors for the Diagnosis of COVID-19

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 390
Author(s):  
Maryia Drobysh ◽  
Almira Ramanaviciene ◽  
Roman Viter ◽  
Arunas Ramanavicius
Keyword(s):  
Field Effect Transistors ◽  
Resonance Field ◽  
Analytical Signal ◽  
Nucleic Acid Hybridization ◽  
Detection Methods ◽  
Label Free ◽  
Infected People ◽  
Label Free Detection ◽  
Main Instrument ◽  
Antigen Antibody

The coronavirus disease 2019 (COVID-19) outbreak caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was proclaimed a global pandemic in March 2020. Reducing the dissemination rate, in particular by tracking the infected people and their contacts, is the main instrument against infection spreading. Therefore, the creation and implementation of fast, reliable and responsive methods suitable for the diagnosis of COVID-19 are required. These needs can be fulfilled using affinity sensors, which differ in applied detection methods and markers that are generating analytical signals. Recently, nucleic acid hybridization, antigen-antibody interaction, and change of reactive oxygen species (ROS) level are mostly used for the generation of analytical signals, which can be accurately measured by electrochemical, optical, surface plasmon resonance, field-effect transistors, and some other methods and transducers. Electrochemical biosensors are the most consistent with the general trend towards, acceleration, and simplification of the bioanalytical process. These biosensors mostly are based on the determination of antigen-antibody interaction and are robust, sensitive, accurate, and sometimes enable label-free detection of an analyte. Along with the specification of biosensors, we also provide a brief overview of generally used testing techniques, and the description of the structure, life cycle and immune host response to SARS-CoV-2, and some deeper details of analytical signal detection principles.

Sign in / Sign up

Export Citation Format

Share Document