Photocatalytic electrosensor for label-free and ultrasensitive detection of BRCA1 gene.
In this work, we have developed an electrochemical sensor for label-free and ultrasensitive detection of DNA (exemplified by breast cancer 1 gene) by using a photocatalytic reaction. Upon recognition of target DNA, the ethidium bromide molecules which were embedded in the hybridized double strand DNA (dsDNA, target DNA and capture DNA) could photo-catalytically generate singlet oxygen upon green light emitting diode irradiation, leading to an efficient cleave of the dsDNA. As a result, the voltammetry for the [Fe(CN)6](3-/4-) was improved remarkably because of less blocking of electrode and weaker charge repulsion. Such a simple strategy provided an ultrasensitive detection of breast cancer 1 gene down to the attomolar level with a broad linear range (10 aM-100 nM). The sensor is by far the most sensitive electrochemical method for detection of breast cancer 1 gene without an amplification procedure. Also the sensor can discriminate mismatched DNA from perfectly matched target DNA with high selectivity. Therefore, simplicity, high sensitivity and specificity provided by this photocatalytic eletrosensor will make it a promising tool for early diagnosis of gene-related diseases.
College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu 610059, PR China.
Xiaojiao
X
Qin
College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu 610059, PR China. Electronic address: xushux@cdut.edu.cn.
Shuxia
S
Xu
College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu 610059, PR China.
Li
L
Deng
College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu 610059, PR China.
Rongfu
R
Huang
College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu 610059, PR China. Electronic address: Zhangxinfeng09@cdut.cn.
Xinfeng
X
Zhang
D019313:BRCA1 Protein / Q000235:genetics*; D015374:Biosensing Techniques / Q000379:methods; D002384:Catalysis; D004247:DNA / Q000032:analysis / Q000097:blood / Q000235:genetics*; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D004996:Ethidium / Q000737:chemistry; D005292:Ferricyanides / Q000737:chemistry; D019398:Genes, BRCA1; D006801:Humans; D008027:Light; D057230:Limit of Detection; D009693:Nucleic Acid Hybridization / Q000379:methods; D026082:Singlet Oxygen / Q000737:chemistry
D019313:BRCA1 Protein; D005292:Ferricyanides; C007931:hexacyanoferrate III; D026082:Singlet Oxygen; D004247:DNA; D004996:Ethidium
BRCA1 gene; Electrochemical DNA sensor; Photocatalytic reaction