New ratio-type label-free fluorescence sensor and application thereof

A ratio-based, label-free technology, applied in the field of detection and chemical analysis, can solve the problems of false positives and false negatives, and achieve the effect of strong specificity, simple operation and high sensitivity

Active Publication Date: 2019-01-11
TIANJIN UNIVERSITY OF SCIENCE AND TECHNOLOGY
View PDF4 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Among them, fluorescence detection technology has attracted much attention due to its ultra-high sensitivity. However, fluorescent probes with a single fluorescent signal have disadvantages that cannot be ignored, and are easily affected by environmental factors, resulting in false negative or false positive results.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • New ratio-type label-free fluorescence sensor and application thereof
  • New ratio-type label-free fluorescence sensor and application thereof
  • New ratio-type label-free fluorescence sensor and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] (1) Synthesis of G-DNA-AgNCs nanoclusters: First, 0.5 μM G-DNA template was annealed (90°C, 8 min), and then 3.0 μM AgNO was added after cooling down to room temperature 3 solution and 3.0 μM NaBH 4 Solution, after overnight reaction at 4°C, the fluorescence intensity of the system was detected with a fluorescence spectrophotometer. The generated G-DNA-AgNCs nanoclusters emit green fluorescence when excited at a wavelength of 470nm, and reach the maximum fluorescence intensity F at 560nm 560 , emits weak red fluorescence under excitation at 610nm wavelength, and reaches the maximum fluorescence intensity F at 685nm 685 ;

[0024] (2)Pb 2+ Construction of sensing system: R-DNA was added to the G-DNA-AgNCs system for hybridization reaction to form silver nanoclusters ( Named ds-DNA-AgNCs), the fluorescence of silver nanoclusters decreased at 560 nm and was greatly enhanced at 685 nm due to the formation of double strands. The novel ratiometric label-free fluorescent ...

Embodiment 2

[0027] figure 2 It is a transmission electron microscope of DNA-AgNCs, which shows that the particle size of ds-DNA-AgNCs is about 3nm.

Embodiment 3

[0029] Optimizing the fluorescence response of the base pair sensing system contained in the duplex formed by R2-1 and G2-1 (F 560 / F 685 ) impact: explore the impact of Pb 2+ In the experiment of fluorescent sensing system factors, Pb 2+ The ratio detection is based on the signal change caused by the release of R2 in G-DNA / R-DNA, and the number of base pairs is an important factor affecting the hybridization process of G-DNA / R-DNA. If the number of complementary base pairs is too small, the Pb-dependent 2+ cleavage site, then Pb 2+ The resulting signal change is not obvious. When the number of complementary base pairs is more, the double-strand is more stable, and it is more difficult to release R2, thereby reducing the detection sensitivity. from image 3 It is known that when the number of complementary base pairs is 9, the presence of R-DNA can effectively convert the green-emitting G-DNA-AgNCs to the red-emitting ds-DNA-AgNCs. Join Pb 2+ Afterwards, green fluoresc...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a new ratio-type label-free fluorescence biosensor for ultra sensitive high-specificity detection of lead ions (Pb2+), which is characterized in that: the constructed fluorescent biosensor is based on fluorescent silver nanoclusters with dual issue synthesized from DNA as a template; a fluorescent probe has the significant advantages of simple synthesis method, good stability and low cost; two character emission peaks are displayed at 560nm (green) and 685nm (red); and the existence of Pb2+ can cause fluorescence at 560nm to enhance and fluorescence at 585nm to decrease, the fluorescence intensity ratio between which (F560 / F685) shows good linear relationship with Pb2+ at the concentration range from 0.001nM to 10nM, has excellent selectivity to Pb2+, and has no obvious responses to copper, zinc, manganese, calcium, cadmium, iron, magnesium, potassium, nickel, chromium and other metal ions. The method provided by the invention can meet the requirement of on-site detection of being fast and accurate, and can be further applied to the development of relevant kits and test notes.

Description

technical field [0001] The invention relates to the field of chemical analysis, in particular to a heavy metal Pb 2+ rapid detection method. The invention belongs to the technical field of detection. Background technique [0002] Lead ion (Pb 2+ ) is a non-degradable environmental pollutant, which is very harmful to human health. For example, even trace amounts of Pb in the blood 2+ It will also cause irreversible brain damage and retardation of mental development to the human body, especially for infants and children whose blood-brain barrier is not perfect. Therefore, the development of reliable ultrasensitive Pb 2+ Sensors to Realize Pb in Environmental and Biological Samples 2+ Detection is of great significance. Currently for the heavy metal Pb 2+ There are many literature reports on detection methods (Chemical Communications, 2015, 51, 979-995.; J.Am.Chem.Soc., 2007, 129, 262-263.; Analytical Chemistry, 2012, 84, 3703-3709.; Chemical Communications, 2011, 47, ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01N33/68G01N21/64
CPCG01N21/6428G01N33/6803
Inventor 刘亚青王娇王硕
Owner TIANJIN UNIVERSITY OF SCIENCE AND TECHNOLOGY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products