title: Ultrasensitive detection of single nucleotide polymorphism in human mitochondrial DNA utilizing ion-mediated cascade surface-enhanced Raman spectroscopy amplification.
abstract: Although surface-enhanced Raman spectroscopy (SERS) has been featured by high sensitivity, additional signal enhancement is still necessary for trace amount of biomolecules detection. In this paper, a SERS amplified approach, featuring "ions-mediated cascade amplification (IMCA)", was proposed by utilizing the dissolved silver ions (Ag(+)) from silver nanoparticles (AgNPs). We found that using Ag(+) as linkage agent can effectively control the gaps between neighboring 4-aminobenzenethiol (4-ABT) encoded gold nanoparticles (AuNPs@4-ABT) to form "hot spots" and thus produce SERS signal output, in which the SERS intensity was proportional to the concentration of Ag(+). Inspired by this finding, the IMCA was utilized for ultrasensitive detection of single nucleotide polymorphism in human mitochondrial DNA (16189T → C). Combining with the DNA ligase reaction, each target DNA binding event could successfully cause one AgNP introduction. By detecting the dissolved Ag(+) from AgNPs using IMCA, low to 3.0 × 10(-5) fm/μL targeted DNA can be detected, which corresponds to extractions from 200 nL cell suspension containing carcinoma pancreatic β-cell lines from diabetes patients. This IMCA approach is expected to be a universal strategy for ultrasensitive detection of analytes and supply valuable information for biomedical research and clinical early diagnosis.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Hunan University , Changsha, 410082, China.
authors.forename: Muling
authors.initials: M
authors.lastname: Shi
authors.forename: Jing
authors.initials: J
authors.lastname: Zheng
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Tan
authors.forename: Guixiang
authors.initials: G
authors.lastname: Tan
authors.forename: Jishan
authors.initials: J
authors.lastname: Li
authors.forename: Yinhui
authors.initials: Y
authors.lastname: Li
authors.forename: Xia
authors.initials: X
authors.lastname: Li
authors.forename: Zhiguang
authors.initials: Z
authors.lastname: Zhou
authors.forename: Ronghua
authors.initials: R
authors.lastname: Yang
mesh_terms: D004272:DNA, Mitochondrial / Q000235:genetics*; D006046:Gold / Q000737:chemistry; D006801:Humans; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D053768:Metal Nanoparticles / Q000737:chemistry; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D010190:Pancreatic Neoplasms / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012834:Silver / Q000737:chemistry; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013499:Surface Properties; D014407:Tumor Cells, Cultured
chemical_list: D004272:DNA, Mitochondrial; D012834:Silver; D006046:Gold