title: Optically encoded multifunctional nanospheres for one-pot separation and detection of multiplex DNA sequences.
abstract: In this study, we report a simple method for simultaneous detection of multiplex DNA sequences, including complementary DNA (cDNA) sequences of HIV and HCV, DNA sequence of HBV, with QDs-encoded fluorescent nanospheres and nano-γ-Fe2O3-coated magnetic nanospheres. Detection was achieved on a fluorescence spectrophotometer without additional auxiliary instruments, and the detection limit was about 100 pM. Here, QDs-encoded fluorescent nanospheres (FNS) with different photoluminescent properties, and magnetic nanospheres (MNS) were separately fabricated by stepwise assembly of hydrophobic QDs or nano-γ-Fe2O3 on the surface of branched poly(ethylene imine) (PEI)-coated nanospheres in precisely controlled amounts, finally followed by silica encapsulation. FNS-labeled probe DNAs and MNS-labeled capture DNAs were used to hybridize with the corresponding targets at the same time. After magnetic separation, the sandwich-structured adducts were measured by fluorescence spectrophotometry. The results indicated that the targets could be detected with high sensitivity. This method is convenient, fast enough, and capable of high anti-interference. Therefore, it is expected to be used for simultaneous detection and separation of multiple targets at high levels of purity and throughput.
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, and State Key Laboratory of Virology, Wuhan University , Wuhan 430072, P.R. China .
authors.forename: Jun
authors.initials: J
authors.lastname: Hu
authors.forename: Cong-Ying
authors.initials: CY
authors.lastname: Wen
authors.forename: Zhi-Ling
authors.initials: ZL
authors.lastname: Zhang
authors.forename: Min
authors.initials: M
authors.lastname: Xie
authors.forename: Jiao
authors.initials: J
authors.lastname: Hu
authors.forename: Min
authors.initials: M
authors.lastname: Wu
authors.forename: Dai-Wen
authors.initials: DW
authors.lastname: Pang
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000097:blood / Q000235:genetics* / Q000302:isolation & purification*; D054118:Nanospheres / Q000737:chemistry*; D055620:Optical Phenomena; D045663:Quantum Dots; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013997:Time Factors
chemical_list: D004247:DNA