Highly sensitive and rapid visual detection of ricin using unmodified gold nanoparticle probes

RSC Advances ◽  
2014 ◽  
Vol 4 (83) ◽  
pp. 43998-44003 ◽  
Author(s):  
Jingting Hu ◽  
Haichao Dai ◽  
Yujing Sun ◽  
Pengjuan Ni ◽  
Yilin Wang ◽  
...  

A sensitive aptamer-based colorimetric biosensor for the detection of ricin using unmodified gold nanoparticles as probe was developed.

RSC Advances ◽  
2014 ◽  
Vol 4 (102) ◽  
pp. 58460-58466 ◽  
Author(s):  
Syazana Abdullah Lim ◽  
Hiroyuki Yoshikawa ◽  
Eiichi Tamiya ◽  
Hartini Mohd Yasin ◽  
Minhaz Uddin Ahmed

This study describes a highly sensitive electrochemical immunosensor for the detection of human chorionic gonadotropin (hCG) that uses gold nanoparticles (AuNP) as the electrochemical label and graphene as electrode material.


2000 ◽  
Vol 72 (1-2) ◽  
pp. 229-235 ◽  
Author(s):  
Robert A. Reynolds ◽  
Chad A. Mirkin ◽  
Robert L. Letsinger

An exceptionally simple and effective DNA detection methodology based on latex microsphere and gold nanoparticle probes has been developed. The latex and gold particle probes, which were functionalized with separate oligonucleotide sequences, undergo hybridization in the presence of target strands that are complementary to both of the probes. Duplex formation thus results in linking of gold nanoparticles to the latex microspheres and a corresponding white-to-red color change, which, because of the particularly large extinction coefficient of the gold nanoparticles, is clearly visible to the naked eye. Background signal caused by unbound gold nanoparticles is significantly reduced by filtering the solution containing the sample and probes through a size-selective cellulose acetate membrane. The unbound gold probes move freely through this membrane while the larger latex particles are trapped. Therefore, if the latex and gold nanoparticles are joined together via the target oligonucleotides, the membrane appears red, indicating a positive test result. If no hybridization takes place, the membrane appears white, indicating a negative result. The lower detection limits for this system are 500 pM for a 24 base single-stranded target and 2.5 nM for a duplex target oligonucleotide.


2016 ◽  
Vol 8 (22) ◽  
pp. 4398-4405 ◽  
Author(s):  
S. Devi ◽  
B. Singh ◽  
A. K. Paul ◽  
S. Tyagi

(A) A schematic representation of the formation of cysteine capped gold nanoparticles and their interaction at pH 5 and 9.3. (B) A schematic representation of the formation of a Meisenheimer complex between cysteine modified gold nanoparticles and TNT, and possible cross-linking between gold nanoparticles bound to the Meisenheimer complex with gold nanoparticle bound cysteine.


2017 ◽  
Vol 53 (54) ◽  
pp. 7477-7480 ◽  
Author(s):  
Juanhua Yang ◽  
Yun Zhang ◽  
Lang Zhang ◽  
Huili Wang ◽  
Jinfang Nie ◽  
...  

This work reports a new nanosensor based on analyte-triggered autocatalytic amplification and label-free gold nanoparticles for the colorimetric detection of Hg2+, Cu2+and Ag+with detection limits less than 3 nM.


2014 ◽  
Vol 6 (13) ◽  
pp. 4507-4511 ◽  
Author(s):  
Dinggui Dai ◽  
Dong Xu ◽  
Xiaodong Cheng ◽  
Yan He

We present a highly sensitive Pb2+ detection method by in situ real-time imaging of Pb2+ catalyzed etching and size reduction of immobilized single gold nanoparticles with darkfield microscopy.


2007 ◽  
Vol 7 (2) ◽  
pp. 712-716 ◽  
Author(s):  
Wenrong Yang ◽  
J. Justin Gooding ◽  
Zhicong He ◽  
Qiong Li ◽  
Guonan Chen

This communication reports an efficient visual detection method of Cu2+ by L-cysteine functionalized gold nanoparticles in aqueous solution. Upon exposure to Cu2+, the gold nanoparticle solution changed from red to blue, in response to surface plasmon absorption of dispersed and aggregated nanoparticles. This colorimetric sensor allows a rapid quantitative assay of Cu2+ down to the concentration range of 10−5 M. Recognition of Cu2+ and formation of the aggregates are proposed to occur via a 2 : 1 sandwich complex between L-cysteine and Cu2+.


2015 ◽  
Vol 7 (5) ◽  
pp. 1878-1883 ◽  
Author(s):  
Wencheng Wang ◽  
Yong Cheng ◽  
Lijun Yan ◽  
Huanhuan Zhu ◽  
Guangjiu Li ◽  
...  

A highly sensitive electrochemical sensor for the detection of dopamine was realized with a double-stranded deoxyribonucleic acid/gold nanoparticles/graphene modified carbon ionic liquid electrode.


Sign in / Sign up

Export Citation Format

Share Document