Cong Yu

Facile detection of latent fingerprints on various substrates based on perylene probe excimer emission

Co-reporter:Fangyuan Wang, Jian Chen, Huipeng Zhou, Wenying Li, Qingfeng Zhang and Cong Yu

Analytical Methods 2014 vol. 6(Issue 3) pp:654-657

Publication Date(Web):29 Oct 2013

DOI:10.1039/C3AY41802B

A new method for the rapid development of latent fingerprints on various substrates based on perylene probe excimer emission has been developed. Our method is simple, rapid, non-toxic, non-flammable, and inexpensive. It shows good potential in individual identity validation related forensic applications.

Real-Time Fluorometric Assay for Acetylcholinesterase Activity and Inhibitor Screening through the Pyrene Probe Monomer–Excimer Transition

Co-reporter:Jian Chen, Dongli Liao, Yan Wang, Huipeng Zhou, Wenying Li, and Cong Yu

Organic Letters 2013 Volume 15(Issue 9) pp:2132-2135

Publication Date(Web):April 16, 2013

DOI:10.1021/ol400619t

A choline labeled pyrene probe (Py-Ch) was designed and synthesized. Poly(vinylsulfonate) (PVS) could induce Py-Ch aggregation. The aggregation and deaggregation process could be finely controlled by the acetylcholinesterase (AChE) enzymatic hydrolysis of Py-Ch. The resulting excimer–monomer transition provided a facile way for real-time AChE activity fluorometric assay and inhibitor screening.

An ultrasensitive chemiluminescence turn-on assay for protease and inhibitor screening with a natural substrate

Co-reporter:Qingfeng Zhang, Wenying Li, Jian Chen, Fangyuan Wang, Yan Wang, Yang Chen and Cong Yu

Chemical Communications 2013 vol. 49(Issue 30) pp:3137-3139

Publication Date(Web):04 Mar 2013

DOI:10.1039/C3CC40906F

A highly sensitive and convenient chemiluminescence (CL) turn-on assay for protease without any label and synthesis has been developed. Cytochrome c was digested by a protease, and heme was released as a peptide–heme conjugate, which greatly enhanced the luminol–H2O2 CL reaction.

In Situ Formation of Metal Coordination Polymer: A Strategy for Fluorescence Turn-On Assay of Acetylcholinesterase Activity and Inhibitor Screening

Co-reporter:Dongli Liao, Jian Chen, Huipeng Zhou, Yan Wang, Yongxin Li, and Cong Yu

Analytical Chemistry 2013 Volume 85(Issue 5) pp:2667

Publication Date(Web):February 4, 2013

DOI:10.1021/ac302971x

A novel method for the sensing of acetylcholinesterase (AChE) activity and inhibitor screening based on the formation of metal coordination polymer has been developed. Acetylthiocholine (ATCh) was selected as the substrate. In the presence of AChE, ATCh was hydrolyzed to thiocholine and acetate. Thiocholine interacted with Ag(I) to form a metal coordination polymer. A positively charged perylene probe (probe 1) was employed. The fluorescence of probe 1 was very efficiently quenched by a polyanion [PVS, poly(vinyl sulfonate)]. In the presence of acetylcholinesterase, the positively charged metal coordination polymer newly formed in situ would interact with PVS, probe 1 monomer molecules were released, and a turn on fluorescence signal was detected. The assay is highly sensitive, a limit of detection of 0.04 mU/mL AChE was obtained. The assay is also highly selective, a number of potential interference proteins (enzymes) were tested, and none of them show noticeable interference. Sensing of AChE inhibitor was also demonstrated. Our assay is fairly simple and inexpensive. We envision that it could be used for the sensitive detection of other hydrolytic enzyme activities with properly selected substrates and for the screening of potential inhibitor drugs.

A fluorescence turn-on method for real-time monitoring of protease activity based on the electron transfer between a fluorophore labeled oligonucleotide and cytochrome c

Co-reporter:Dongli Liao, Yongxin Li, Jian Chen, Cong Yu

Analytica Chimica Acta 2013 Volume 784() pp:72-76

Publication Date(Web):19 June 2013

DOI:10.1016/j.aca.2013.04.066

•Rapid detection of protease activity with fairly good sensitivity and selectivity.•A turn-on fluorescence assay reduces the likelihood of false positive signals.•Cytochrome c efficiently quench the fluorescence of the FAM single stranded DNA.•The enzymatic reaction could be monitored in real-time.•The assay could be used for the screening of potential protease inhibitors.A new continuous fluorescence turn-on assay for protease activity and inhibitor screening has been developed. A fluorophore labeled single stranded DNA (FAM-DNA) and cytochrome c (cyt c) were employed. The fluorescence of the FAM-DNA was efficiently quenched when binding to cyt c, through the electron transfer between the FAM fluorophore and the heme cofactor of cyt c. In the presence of a protease, such as trypsin, cyt c was digested into small peptide fragments. The FAM-DNA was released, which resulted in the recovery of the FAM fluorescence. The rate of the cyt c digestion could be reduced via the addition of an inhibitor. As a result, reduced degree of the fluorescence recovery was obtained. The limit of detection of our assay is 1 nM trypsin and the IC50 values are 3.23 μg mL−1 and 0.303 μg mL−1 for the inhibitor from egg white and the inhibitor from soybean, respectively. Our method could be used for the sensing of protease activity for various biochemical applications, and for the screening of protease inhibitors as drugs for the treatment of various related diseases.

Papain-directed synthesis of luminescent gold nanoclusters and the sensitive detection of Cu2+

Co-reporter:Yang Chen, Yan Wang, Chuanxi Wang, Wenying Li, Huipeng Zhou, Huping Jiao, Quan Lin, Cong Yu

Journal of Colloid and Interface Science 2013 Volume 396() pp:63-68

Publication Date(Web):15 April 2013

DOI:10.1016/j.jcis.2013.01.031

Highly fluorescent papain stabilized gold nanoclusters (NCs) have been synthesized through a simple wet chemical route. Papain was used for the first time as an effective capping and reducing agent for these clusters. The optimal conditions for the synthesis of the gold nanoclusters, including the concentrations of papain and NaOH, reaction time and temperature, were investigated. The as-prepared Au clusters show intense red emission at ∼660 nm (QY ∼4.3%) and are uniform in size. The clusters are quite stable and the intense red emission remained unchanged at a buffer pH range of 6–12. The fluorescent Au NCs were then used as a label-free probe for the sensitive detection of Cu2+. A limit of detection of 3 nM was obtained. The sensing strategy is also highly selective against the various potential interference ions.Graphical abstractHighlights► A simple and “green” approach has been developed to synthesize the papain-Au nanoclusters. ► Papain is a commercially available inexpensive protein and could be obtained in large quantities. ► The nanoclusters show intense red emission in both solution and powder forms. ► The red emission remained unchanged after ∼3 months and at a buffer pH range of 6–12. ► The use of these Au clusters for the simple, sensitive, selective, and label-free cupric ion detection has been demonstrated.

Real-Time Fluorescence Turn-On Detection of Alkaline Phosphatase Activity with a Novel Perylene Probe

Co-reporter:Jian Chen;Huping Jiao;Wenying Li;Dongli Liao;Dr. Huipeng Zhou;Dr. Cong Yu

Chemistry – An Asian Journal 2013 Volume 8( Issue 1) pp:276-281

Publication Date(Web):

DOI:10.1002/asia.201200880

Abstract

A tetracationic perylene probe (probe 2) was designed and synthesized. Probe 1 was used for the real-time fluorescence turn-on assay of alkaline phosphatase (ALP) activity and inhibitor screening. Probe 1 monomer fluorescence could be very efficiently quenched by ATP through the formation of an ATP/probe 1 complex. ALP triggered the degradation of ATP, the breakdown of the ATP/probe 1 complex, and the recovery of the probe 1 monomer fluorescence. In the presence of an ALP inhibitor, a decrease in fluorescence recovery was observed.

Polymer-Templated Perylene-Probe Noncovalent Self-Assembly: A New Strategy for Label-Free Ultrasensitive Fluorescence Turn-On Biosensing

Co-reporter:Yan Wang;Jian Chen;Dr. Huping Jiao;Yang Chen;Wenying Li;Qingfeng Zhang;Dr. Cong Yu

Chemistry - A European Journal 2013 Volume 19( Issue 38) pp:12846-12852

Publication Date(Web):

DOI:10.1002/chem.201203998

Abstract

A new label-free fluorescence turn-on strategy for highly sensitive biosensing has been developed. A negatively charged perylene probe was synthesized. Polycations could induce aggregation of the perylene probe through noncovalent interactions and the fluorescence of the probe’s monomer was efficiently quenched. Upon addition of a single-stranded nucleic acid, competitive binding of the negatively charged nucleic acid (a polyanion) to the cationic polymer resulted in the release of a monomer and thus a turn-on fluorescence signal was detected. Without the use of any amplification techniques, a detection limit of 2 pM DNA was obtained. Based on these results, an assay strategy for the highly sensitive detection of alkaline phosphatase (ALP) activity has been demonstrated. λ Exonuclease (λ exo) could degrade 5′-phosphorylated single-stranded DNA. However, when the DNA sample was treated with ALP, the phosphate functional group was removed by ALP and it could no longer be degraded by λ exo. Binding of the DNA to the perylene probe–polycation complex resulted in a turn-on fluorescence signal, which could be used for sensing of ALP. The method is highly sensitive, a limit of detection as low as 0.02 mU mL⁻¹ ALP was obtained. Our method is simple, convenient, highly sensitive, and inexpensive.

Label free fluorescence turn-on detection of polynucleotide kinase activity with a perylene probe

Co-reporter:Huping Jiao, Bin Wang, Jian Chen, Dongli Liao, Wenying Li and Cong Yu

Chemical Communications 2012 vol. 48(Issue 63) pp:7862-7864

Publication Date(Web):19 Jun 2012

DOI:10.1039/C2CC32644B

A single stranded oligonucleotide could induce aggregation of a perylene probe, the probe's monomer fluorescence was efficiently quenched. However, when the oligonucleotide was 5′-phosphorylated by polynucleotide kinase, it could be very efficiently degraded by lambda exonuclease, probe monomers were released, and a turn on fluorescence signal was detected.

A label-free real time fluorometric assay for protease and inhibitor screening with a released heme

Co-reporter:Wenying Li, Jian Chen, Huping Jiao, Qingfeng Zhang, Huipeng Zhou and Cong Yu

Chemical Communications 2012 vol. 48(Issue 81) pp:10123-10125

Publication Date(Web):24 Aug 2012

DOI:10.1039/C2CC35374A

A label free continuous assay for protease activity and inhibitor screening has been developed. A protease (trypsin) could digest hemoglobin. Free heme molecules were released. Strong π–π stacking and hydrophobic interactions with the perylene probe resulted in efficient quenching of the probe's monomer fluorescence.

KF polymerase-based fluorescence aptasensor for the label-free adenosine detection

Co-reporter:Dongli Liao, Huping Jiao, Bin Wang, Quan Lin and Cong Yu

Analyst 2012 vol. 137(Issue 4) pp:978-982

Publication Date(Web):20 Dec 2011

DOI:10.1039/C2AN15809D

We have developed a simple, inexpensive, and label-free method for the selective detection of adenosine. Klenow fragment polymerase (KF polymerase) is a commonly-used 5′ to 3′ DNA polymerase, it also has 3′ to 5′ exonuclease activity that can digest single-stranded DNA. An adenosine binding DNA aptamer was employed, the aptamer was split into two pieces of single-stranded DNA (aptamer-A1 + aptamer-A2). Without the addition of adenosine, aptamer-A1 and aptamer-A2 existed as single-stranded DNA which could be efficiently degraded by the exonuclease activity of KF polymerase. Much reduced background fluorescence was obtained when SYBR Green dye was added. However, in the presence of adenosine, aptamer-A1 and aptamer-A2 bound to adenosine, and hybridization of the complementary sequences resulted in the formation of a duplex DNA structure, which could initiate DNA polymerization. The addition of SYBR Green dye resulted in a very high fluorescence enhancement, which could be used for the quantification of adenosine.

Detection of silver(I) ions based on the controlled self-assembly of a perylene fluorescence probe

Co-reporter:Yue Yang, Wenying Li, Hong Qi, Qingfeng Zhang, Jian Chen, Yan Wang, Bin Wang, Shujie Wang, Cong Yu

Analytical Biochemistry 2012 Volume 430(Issue 1) pp:48-52

Publication Date(Web):1 November 2012

DOI:10.1016/j.ab.2012.07.024

In the current work, we report a label-free fluorescence turn-on approach for the sensitive and selective sensing of Ag+. A cationic perylene derivative, compound A, was used as the fluorescence probe. Compound A monomer is strongly fluorescent, and the fluorescence can be efficiently quenched through self-aggregation (self-assembly). A cytosine (C)-rich oligonucleotide, oligo-C, was employed. In the absence of Ag+, oligo-C induced strong compound A aggregation due to electrostatic interactions in aqueous media, and very weak fluorescence signal was detected. However, in the presence of Ag+, the specific interactions between oligo-C and Ag+ induced hairpin structure formation of oligo-C through C–Ag+–C bonding interactions. Oligo-C binding to compound A aggregates was weakened; therefore, compound A monomer could be released and detected. The intensity of the fluorescence signal was directly related to the amount of Ag+ added to the assay solution. Our method is highly sensitive—a limit of detection of 5 nM was obtained—and also very selective. Ag+ detection in complex sample mixtures was also demonstrated.

Perylene probe induced gold nanoparticle aggregation

Co-reporter:Bin Wang, Qiankun Zhu, Dongli Liao and Cong Yu

Journal of Materials Chemistry A 2011 vol. 21(Issue 13) pp:4821-4826

Publication Date(Web):17 Feb 2011

DOI:10.1039/C0JM04527F

In the present work, we have studied the aggregation of gold nanoparticles (Au-NPs) induced by a cationic perylene probe (compound 1). The compound 1 free monomer contains a large planar aromatic ring structure that could be efficiently adsorbed onto the surface of the Au-NPs. The strong π–π stacking and hydrophobic interactions among compound 1probe molecules adsorbed on adjacent nanoparticles, and the neutralization of the Au-NP surface citrate ion negative charges induced rapid aggregation of the Au-NPs, and evident UV-vis spectra and solution color changes. The use of this observation for a label-free selective sensing of mercury ion has been demonstrated.

Superquencher formation vianucleic acid induced noncovalent perylene probe self-assembly

Co-reporter:Bin Wang, Huping Jiao, Wenying Li, Dongli Liao, Fangyuan Wang and Cong Yu

Chemical Communications 2011 vol. 47(Issue 37) pp:10269-10271

Publication Date(Web):22 Aug 2011

DOI:10.1039/C1CC13606B

A fluorophore labeled oligonucleotide could induce aggregation of a positively charged perylene probe. The perylene aggregate could very efficiently quench the fluorescence of the labeled fluorophore. Based on this observation, a new method for the highly sensitive and selective detection of a protein has been developed.

Fluorescence turn-on detection of a protein through the displaced single-stranded DNA binding protein binding to a molecular beacon

Co-reporter:Dan Tang, Dongli Liao, Qiankun Zhu, Fangyuan Wang, Huping Jiao, Yujing Zhang and Cong Yu

Chemical Communications 2011 vol. 47(Issue 19) pp:5485-5487

Publication Date(Web):11 Apr 2011

DOI:10.1039/C1CC10316D

A new approach has been developed for the highly sensitive and selective sensing of a protein. Lysozyme binding to its aptamer prevents SSB protein binding, and the subsequent binding of the free SSB protein to a molecular beacon results in a turn-on fluorescence signal, which can be used for lysozyme quantification.

Nucleic acid G-quadruplex based label-free fluorescence turn-on potassium selective sensing

Co-reporter:Xiangyu Yang, Dan Liu, Ping Lu, Yujing Zhang and Cong Yu

Analyst 2010 vol. 135(Issue 8) pp:2074-2078

Publication Date(Web):28 Jun 2010

DOI:10.1039/C0AN00106F

We report a label-free fluorescence turn-on approach for the selective sensing of potassium. A properly selected G-rich oligonucleotide (oligo-Y) folded into stable quadruplex structure when mixed with potassium in an aqueous solution. Single-stranded nucleic acid specific nuclease was subsequently added. Since an oligonucleotide in quadruplex structure is markedly more resistant to nuclease digestion than in its random coil conformation, oligo-Y digestion by nuclease was considerably slow. On the other hand, oligo-Y mixed with other common mono- or divalent ions was completely digested in 5 min under our experimental conditions because no quadruplex or less stable quadruplex was formed. Oligo-Y in potassium was subsequently mixed with a positively charged pyrene probe. Electrostatic interactions between oligo-Y (a polyanion) and the probe induced aggregation of the probe, which in turn induced strong pyrene excimer emission. The intensity of the induced excimer emission was directly proportional to the amount of potassium added. Our method shows good sensitivity, and good selectivity against other common interference ions.

Label-free selective sensing of mercury(II) via reduced aggregation of the perylene fluorescent probe

Co-reporter:Bin Wang, Fangyuan Wang, Huping Jiao, Xiangyu Yang and Cong Yu

Analyst 2010 vol. 135(Issue 8) pp:1986-1991

Publication Date(Web):28 Jun 2010

DOI:10.1039/C0AN00174K

In the present work, we report a fluorescence turn-on approach for the sensitive and selective detection of Hg2+. A cationic perylene derivative (compound 1) was used as the fluorescence probe, and a thymine-rich oligonucleotide (oligo-M) was employed for the specific interaction with Hg2+. Compound 1 shows strong tendency to self-aggregate into linear chain structures in aqueous media because of the π–π stacking interactions of its planar aromatic ring structure. The compound 1 free monomer is strongly fluorescent, whereas its aggregates are not fluorescent. When oligo-M and compound 1 were mixed, oligo-M induced strong compound 1 aggregation and resulted in significant fluorescence quenching. In the presence of Hg2+, the specific interactions between oligo-M and Hg2+ induced hairpin structure formation of oligo-M and thus weakened its binding to compound 1 aggregates. As a result, free probe monomers were released, and increased fluorescence was observed. The fluorescence intensity increase was in direct proportion to the concentration of Hg2+ added. Our method provides a simple, fast, and efficient means for Hg2+ quantification, it is highly sensitive with a limit of detection of 1 nM, and is also highly selective against other common metal ions.

Fluorescence Turn-On Detection of a Protein through the Reduced Aggregation of a Perylene Probe

Co-reporter:Bin Wang Dr.

Angewandte Chemie International Edition 2010 Volume 49( Issue 8) pp:1485-1488

Publication Date(Web):

DOI:10.1002/anie.200905237

Fluorescence Turn-On Detection of a Protein through the Reduced Aggregation of a Perylene Probe

Co-reporter:Bin Wang Dr.

Angewandte Chemie 2010 Volume 122( Issue 8) pp:1527-1530

Publication Date(Web):

DOI:10.1002/ange.200905237

Nucleic Acid-Induced Aggregation and Pyrene Excimer Formation

Co-reporter:Ruixing Zhang, Dan Tang, Ping Lu, Xiangyu Yang, Dongli Liao, Yujing Zhang, Mingjun Zhang, Cong Yu and Vivian W. W. Yam

Organic Letters 2009 Volume 11(Issue 19) pp:4302-4305

Publication Date(Web):September 1, 2009

DOI:10.1021/ol901607g

Nucleic acid was found to induce the aggregation of the positively charged pyrene probe (compound 1); as a result, strong pyrene excimer emission was observed. The intensity of the excimer emission was dependent on the concentration of the pyrene probe and the oligonucleotide length, sequence, and concentration. These results suggest a new strategy for label-free nucleic acid-based biosensing applications.

Facile detection of latent fingerprints on various substrates based on perylene probe excimer emission

Co-reporter:

Analytical Methods (2009-Present) 2014 - vol. 6(Issue 3) pp:

Publication Date(Web):

DOI:10.1039/C3AY41802B

A new method for the rapid development of latent fingerprints on various substrates based on perylene probe excimer emission has been developed. Our method is simple, rapid, non-toxic, non-flammable, and inexpensive. It shows good potential in individual identity validation related forensic applications.

An ultrasensitive chemiluminescence turn-on assay for protease and inhibitor screening with a natural substrate

Co-reporter:Qingfeng Zhang, Wenying Li, Jian Chen, Fangyuan Wang, Yan Wang, Yang Chen and Cong Yu

Chemical Communications 2013 - vol. 49(Issue 30) pp:NaN3139-3139

Publication Date(Web):2013/03/04

DOI:10.1039/C3CC40906F

A highly sensitive and convenient chemiluminescence (CL) turn-on assay for protease without any label and synthesis has been developed. Cytochrome c was digested by a protease, and heme was released as a peptide–heme conjugate, which greatly enhanced the luminol–H2O2 CL reaction.

Label free fluorescence turn-on detection of polynucleotide kinase activity with a perylene probe

Co-reporter:Huping Jiao, Bin Wang, Jian Chen, Dongli Liao, Wenying Li and Cong Yu

Chemical Communications 2012 - vol. 48(Issue 63) pp:NaN7864-7864

Publication Date(Web):2012/06/19

DOI:10.1039/C2CC32644B

A single stranded oligonucleotide could induce aggregation of a perylene probe, the probe's monomer fluorescence was efficiently quenched. However, when the oligonucleotide was 5′-phosphorylated by polynucleotide kinase, it could be very efficiently degraded by lambda exonuclease, probe monomers were released, and a turn on fluorescence signal was detected.

Fluorescence turn-on detection of a protein through the displaced single-stranded DNA binding protein binding to a molecular beacon

Co-reporter:Dan Tang, Dongli Liao, Qiankun Zhu, Fangyuan Wang, Huping Jiao, Yujing Zhang and Cong Yu

Chemical Communications 2011 - vol. 47(Issue 19) pp:NaN5487-5487

Publication Date(Web):2011/04/11

DOI:10.1039/C1CC10316D

A new approach has been developed for the highly sensitive and selective sensing of a protein. Lysozyme binding to its aptamer prevents SSB protein binding, and the subsequent binding of the free SSB protein to a molecular beacon results in a turn-on fluorescence signal, which can be used for lysozyme quantification.

Superquencher formation vianucleic acid induced noncovalent perylene probe self-assembly

Co-reporter:Bin Wang, Huping Jiao, Wenying Li, Dongli Liao, Fangyuan Wang and Cong Yu

Chemical Communications 2011 - vol. 47(Issue 37) pp:NaN10271-10271

Publication Date(Web):2011/08/22

DOI:10.1039/C1CC13606B

A fluorophore labeled oligonucleotide could induce aggregation of a positively charged perylene probe. The perylene aggregate could very efficiently quench the fluorescence of the labeled fluorophore. Based on this observation, a new method for the highly sensitive and selective detection of a protein has been developed.

Perylene probe induced gold nanoparticle aggregation

Co-reporter:Bin Wang, Qiankun Zhu, Dongli Liao and Cong Yu

Journal of Materials Chemistry A 2011 - vol. 21(Issue 13) pp:NaN4826-4826

Publication Date(Web):2011/02/17

DOI:10.1039/C0JM04527F

In the present work, we have studied the aggregation of gold nanoparticles (Au-NPs) induced by a cationic perylene probe (compound 1). The compound 1 free monomer contains a large planar aromatic ring structure that could be efficiently adsorbed onto the surface of the Au-NPs. The strong π–π stacking and hydrophobic interactions among compound 1probe molecules adsorbed on adjacent nanoparticles, and the neutralization of the Au-NP surface citrate ion negative charges induced rapid aggregation of the Au-NPs, and evident UV-vis spectra and solution color changes. The use of this observation for a label-free selective sensing of mercury ion has been demonstrated.

A label-free real time fluorometric assay for protease and inhibitor screening with a released heme

Co-reporter:Wenying Li, Jian Chen, Huping Jiao, Qingfeng Zhang, Huipeng Zhou and Cong Yu

Chemical Communications 2012 - vol. 48(Issue 81) pp:NaN10125-10125

Publication Date(Web):2012/08/24

DOI:10.1039/C2CC35374A

A label free continuous assay for protease activity and inhibitor screening has been developed. A protease (trypsin) could digest hemoglobin. Free heme molecules were released. Strong π–π stacking and hydrophobic interactions with the perylene probe resulted in efficient quenching of the probe's monomer fluorescence.

TOPICS

Abstract

Abstract