title: A molecular beacon microarray based on a quantum dot label for detecting single nucleotide polymorphisms.
abstract: In this work, we report the application of streptavidin-coated quantum dot (strAV-QD) in molecular beacon (MB) microarray assays by using the strAV-QD to label the immobilized MB, avoiding target labeling and meanwhile obviating the use of amplification. The MBs are stem-loop structured oligodeoxynucleotides, modified with a thiol and a biotin at two terminals of the stem. With the strAV-QD labeling an "opened" MB rather than a "closed" MB via streptavidin-biotin reaction, a sensitive and specific detection of label-free target DNA sequence is demonstrated by the MB microarray, with a signal-to-background ratio of 8. The immobilized MBs can be perfectly regenerated, allowing the reuse of the microarray. The MB microarray also is able to detect single nucleotide polymorphisms, exhibiting genotype-dependent fluorescence signals. It is demonstrated that the MB microarray can perform as a 4-to-2 encoder, compressing the genotype information into two outputs.
authors.affiliation: State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, China.
authors.forename: Qingsheng
authors.initials: Q
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, China.
authors.forename: Zhixiong
authors.initials: Z
authors.lastname: Bai
authors.affiliation: State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, China.
authors.forename: Yuqian
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, China. Electronic address: sunqj@seu.edu.cn.
authors.forename: Qingjiang
authors.initials: Q
authors.lastname: Sun
mesh_terms: D004247:DNA / Q000032:analysis / Q000235:genetics*; D004252:DNA Mutational Analysis / Q000295:instrumentation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D015336:Molecular Probe Techniques / Q000295:instrumentation*; D015335:Molecular Probes; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D045663:Quantum Dots; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA / Q000295:instrumentation*; D013050:Spectrometry, Fluorescence / Q000295:instrumentation; D013194:Staining and Labeling / Q000379:methods
chemical_list: D015335:Molecular Probes; D004247:DNA
keywords: DNA microarray; Encoder; Molecular beacon; Quantum dots; Single nucleotide polymorphism