Improving the fluorescence detection limit with positively charged carbon nanostructures as a low background signal platform

The Analyst ◽  
2014 ◽  
Vol 139 (9) ◽  
pp. 2114-2117 ◽  
Author(s):  
Xiulan He ◽  
Li Zhang ◽  
Hetong Qi ◽  
Ping Yu ◽  
Junjie Fei ◽  
...  
Keyword(s):  
Detection Limit ◽  
Fluorescence Detection ◽  
Carbon Nanostructures ◽  
Fluorescent Dyes ◽  
Energy Transfer Efficiency ◽  
Background Signal ◽  
Low Background ◽  
Carbon Structures ◽  
New Strategy ◽  
Positively Charged

We have demonstrated a new strategy to improve the fluorescence detection limit by enhancing the energy transfer efficiency between carbon structures and fluorescent dyes using polyimidazolium-functionalized carbon nanostructures as a low background signal platform.

Alcohol Determination by HPLC with Postcolumn Derivatization Based on the Thiosulfate-catalyzed Reaction of Alcohols and Cerium(IV) and Fluorescence Detection of Cerium(III)

2020 ◽  
Vol 16 ◽  
Author(s):  
Ikko Mikami ◽  
Eri Shibayama ◽  
Kengo Takagi
Keyword(s):  
Detection Limit ◽  
Fluorescence Detection ◽  
Reaction Rate ◽  
Detection Method ◽  
Fluorescence Detector ◽  
Reaction Solution ◽  
Optimum Detection ◽  
Postcolumn Derivatization ◽  
Sensitive Method

Background: Determination of a reducing substance based on the reaction between Ce(IV) and a reducing substance and fluorescence detection of Ce(III) generated has been reported as a selective and sensitive method. However, this method could not be applied to the determination of alcohol due to the low reaction rate of alcohol and Ce(IV). Objective: We found that thiosulfate catalytically enhanced reaction of alcohols (such as, methanol, ethanol, and propanol) and Ce(IV). Utilizing this effect, we developed a new method for the determination of alcohols. Results: In the presence of thiosulfate, an increase in fluorescence intensity was detected by injecting alcohol at concentrations of several millimolar, whereas it was not observed even at the concentration of 10% v/v (2 M for ethanol) in the absence of thiosulfate. The optimum detection conditions were determined to be 4.0 mM Ce(IV) sulfate and 0.50 mM thiosulfate, and the detection limit (S/N = 3) of ethanol under these conditions was 1 mM. In the calibration curves, changes in the slope were observed when the alcohol concentrations were approximately 10–25 mM. Using a thiosulfate solution containing ethanol as the reaction solution, a calibration curve without any change in slope was obtained, although the concentration of ethanol at the detection limit increased. The alcohols in the liquor and fuel were successfully analyzed using the proposed detection method as a postcolumn reaction. Conclusion: This new alcohol detection method using a versatile fluorescence detector can be applied to the postcolumn reaction of HPLC omitting need of time-consuming pretreatment processes.

scholarly journals Digitally Patterned Mesoporous Carbon Nanostructures of Colorless Polyimide for Transparent and Flexible Micro-Supercapacitor

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2547
Author(s):  
Hyeonwoo Kim ◽  
Suwon Hwang ◽  
Taeseung Hwang ◽  
Jung Bin In ◽  
Junyeob Yeo
Keyword(s):  
Carbon Nanostructures ◽  
Specific Area ◽  
Bending Test ◽  
Chemical Compositions ◽  
Carbon Structure ◽  
Carbon Structures ◽  
Direct Laser ◽  
Mechanical Bending ◽  
Minimal Reduction ◽  
High Flexibility

Here, we demonstrate the fabrication of a flexible and transparent micro-supercapacitor (MSC), using colorless polyimide (CPI) via a direct laser writing carbonization (DLWC) process. The focused laser beam directly carbonizes the CPI substrate and generates a porous carbon structure on the surface of the CPI substrate. Fluorine, which is one of the chemical compositions of CPI, can enhance the specific area and the conductivity of the carbon electrode by creating micropores in carbon structures during carbonization. Thus, the fabricated carbonized CPI-based MSC shows enhanced specific capacitance (1.20 mF at 10 mV s−1) and better transmittance (44.9%) compared to the conventional PI-based MSC. Additionally, the fabricated carbonized CPI-based MSC shows excellent cyclic performance with minimal reduction (<~10%) in 3000 cycles and high capacitance retention under mechanical bending test conditions. Due to its high flexibility, transparency, and capacitance, we expect that carbonized CPI-based MSC can be further applied to various flexible and transparent applications.

Sensitive mutant DNA biomarker detection based on magnetic nanoparticles and nicking endonuclease assisted fluorescence signal amplification

RSC Advances ◽  
2015 ◽  
Vol 5 (26) ◽  
pp. 20020-20024 ◽  
Author(s):  
Na Li ◽  
Zhong Feng Gao ◽  
Bei Hua Kang ◽  
Nian Bing Li ◽  
Hong Qun Luo
Keyword(s):  
Magnetic Nanoparticles ◽  
Signal Amplification ◽  
Fluorescence Signal ◽  
Biomarker Detection ◽  
Background Signal ◽  
Sensitive Mutant ◽  
Nicking Endonuclease ◽  
Low Background ◽  
Target Dna ◽  
Fluorescence Signal Amplification

Amplified fluorescence target DNA detection was developed combining nicking endonuclease assisted target recycling and magnetic nanoparticles with low background signal.

Target-controlled gating liposome “off–on” cascade amplification for sensitive and accurate detection of phospholipase D in breast cancer cells with a low-background signal

2016 ◽  
Vol 52 (70) ◽  
pp. 10660-10663 ◽  
Author(s):  
Qingwang Xue ◽  
Wei Jiang ◽  
Lei Wang
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Phospholipase D ◽  
Breast Cancer Cells ◽  
Detection Method ◽  
Background Signal ◽  
Low Background ◽  
Accurate Detection ◽  
Cascade Amplification

Here we developed a simple, sensitive and accurate PLD detection method based on a target-controlled gating liposome (TCGL) “off–on” cascade amplified strategy and personal glucose meters (PGMs).

Fabrication of a low background signal glucose biosensor with 3D network materials as the electrocatalyst

2019 ◽  
Vol 567 ◽  
pp. 63-71 ◽  
Author(s):  
Huiling Tang ◽  
Dehao Cai ◽  
Tianyao Ren ◽  
Ping Xiong ◽  
Yu Liu ◽  
...  
Keyword(s):  
Glucose Biosensor ◽  
Background Signal ◽  
Low Background ◽  
3D Network

scholarly journals Multilayer Polyelectrolyte Films Functionalized by Insertion of Defensin: a New Approach to Protection of Implants from Bacterial Colonization

2004 ◽  
Vol 48 (10) ◽  
pp. 3662-3669 ◽  
Author(s):  
O. Etienne ◽  
C. Picart ◽  
C. Taddei ◽  
Y. Haikel ◽  
J. L. Dimarcq ◽  
...  
Keyword(s):  
Antimicrobial Peptide ◽  
Micrococcus Luteus ◽  
Bacterial Colonization ◽  
Streaming Potential ◽  
Multilayer Films ◽  
Microbial Infection ◽  
Host Protection ◽  
New Strategy ◽  
Local Host ◽  
Positively Charged

ABSTRACT Infection of implanted materials by bacteria constitutes one of the most serious complications following prosthetic surgery. In the present study, we developed a new strategy based on the insertion of an antimicrobial peptide (defensin from Anopheles gambiae mosquitoes) into polyelectrolyte multilayer films built by the alternate deposition of polyanions and polycations. Quartz crystal microbalance and streaming potential measurements were used to follow step by step the construction of the multilayer films and embedding of the defensin within the films. Antimicrobial assays were performed with two strains: Micrococcus luteus (a gram-positive bacterium) and Escherichia coli D22 (a gram-negative bacterium). The inhibition of E. coli D22 growth at the surface of defensin-functionalized films was found to be 98% when 10 antimicrobial peptide layers were inserted in the film architecture. Noticeably, the biofunctionalization could be achieved only when positively charged poly(l-lysine) was the outermost layer of the film. On the basis of the results of bacterial adhesion experiments observed by confocal or electron microscopy, these observations could result from the close interaction of the bacteria with the positively charged ends of the films, which allows defensin to interact with the bacterial membrane structure. These results open new possibilities for the use of such easily built and functionalized architectures onto any type of implantable biomaterial. The modified surfaces are active against microbial infection and represent a novel means of local host protection.

Spectrofluorometric Determination of BAY Vp 2674 Residues in Poultry Tissues

1987 ◽  
Vol 70 (5) ◽  
pp. 813-818 ◽  
Author(s):  
T Bill Waggoner ◽  
Malcolm C Bowman
Keyword(s):  
Detection Limit ◽  
Fluorescence Detection ◽  
Coefficient Of Variation ◽  
Organic Extract ◽  
Spectrofluorometric Determination ◽  
Poultry Tissues ◽  
Liquid Chromatographic

Abstract A spectrofluorometric (SPF) method is described for determination of residues of BAY Vp 2674 in chicken and turkey tissues. The drug is extracted from tissues with dichloromethane-methanol. The organic extract is concentrated to near dryness and cleaned up by a series of partitionings with n-hexane, then dichloromethane against pH 2 buffer and dichloromethane against pH 12 buffer. The drug is partitioned into dichloromethane from pH 7 buffer and concentrated to dryness. The residue is dissolved in pH 3.5 buffer for SPF analysis at 282 nm (excitation) and 445 nm (emission). Recoveries of BAY Vp 2674 added to chicken and turkey tissues at levels of 0.05, 0.1, and 0.2 ppm range from 86 to 92% with a coefficient of variation of 3.4-10.1%. Detection limit is 0.02 ppm. A liquid chromatographic confirmatory procedure is also described, with ultraviolet and fluorescence detection

scholarly journals Single-photon laser-induced fluorescence detection of nitric oxide at sub-parts-per-trillion mixing ratios

2020 ◽  
Vol 13 (5) ◽  
pp. 2425-2439 ◽  
Author(s):  
Andrew W. Rollins ◽  
Pamela S. Rickly ◽  
Ru-Shan Gao ◽  
Thomas B. Ryerson ◽  
Steven S. Brown ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Detection Limit ◽  
Fluorescence Detection ◽  
Narrow Band ◽  
Single Photon ◽  
Spectral Feature ◽  
Laser Induced Fluorescence ◽  
Mixing Ratios ◽  
Laser Induced Fluorescence Detection ◽  
Direct Measurements

Abstract. We describe a newly developed single-photon laser-induced fluorescence sensor for measurements of nitric oxide (NO) in the atmosphere. Rapid tuning of a narrow-band laser on and off of a rotationally resolved NO spectral feature near 215 nm and detection of the red-shifted fluorescence provides for interference-free direct measurements of NO with a detection limit of 1 part per trillion by volume (pptv) for 1 s of integration, or 0.3 pptv for 10 s of integration. Uncertainty in the sensitivity of the instrument is typically ±6–9 %, with no known interferences. Uncertainty in the zero of the detector is shown to be <0.2 pptv. The instrument was deployed on the NASA DC-8 aircraft during the NASA/NOAA FIREX-AQ experiment (Fire Influence on Regional to Global Environments Experiment – Air Quality) during July–September 2019 and provided more than 140 h of NO measurements over 22 flights, demonstrating the ability of this instrument to operate routinely and autonomously. Comparisons with a seasoned chemiluminescence sensor during FIREX-AQ in a variety of chemical environments provides validation and confidence in the accuracy of this technique.

Research of Laser Induced Fluorescence Detection Techniques Based on Microfluidic Devices

2014 ◽  
Vol 989-994 ◽  
pp. 2761-2763
Author(s):  
Yong Qiang Cheng ◽  
Cui Lian Guo ◽  
Bin Zhao ◽  
Li Yang
Keyword(s):  
Detection Limit ◽  
Fluorescence Detection ◽  
Recent Progress ◽  
Biochemical Analysis ◽  
Detection Method ◽  
Microfluidic Devices ◽  
Laser Induced Fluorescence ◽  
Detection Techniques ◽  
Laser Induced Fluorescence Detection ◽  
Optical Structure

Laser induced fluorescence (LIF) detection technique is one of the most sensitive detection method in micro total analytical systems (μTAS) as its good monochromaticity, strong collimation and high optical density. It is widely used in biochemical analysis systems and the detection limit could reach 10-9-10-12mol/L. Due to the important role in μTAS, different optical structure arrangements of LIF detection techniques were continuously developed. We reviewed the recent progress of the optical structure arrangement and the applications of the LIF detection techniques.

Sign in / Sign up

Export Citation Format

Share Document