Application Of Microfluidic Biosensor Based On SERS Signal Amplification

Tumor markers in the early stage of the disease,the concentration of active molecules is very low,so the use of the high sensitivity detection of nucleic acids is very important for the early diagnosis of the disease and subsequent treatment.In this paper,the micro fluidic chip technique and surface enhanced Raman spectroscopy in combination with,the field rapidly and accurately,less,good selectivity in biological analysis,through the build target replacement cycle and multifunctional intelligent hairpin probe DNA caused by cycle amplification method,by using nano Au bio bar code technology,quantitative accuracy of tumor mark mi R-203 were detected.This paper is mainly divided into two parts as following:The microfluidic chip technique and surface enhanced Raman spectroscopy in combination with,a poly dimethyl siloxane(PDMS)Polydimethylsiloxane/glass micro fluidic chip is fabricated,using the chip is two-layer sandwich type of Ti-Au and concentric circles type microelectrode design,through the micro injection pump,micro tube DNA reaction solution,cells were injected to the chip reaction,until the end of the reaction,the reaction liquid moved to detecting groove,Raman spectroscopy detection.Based on the surface enhanced Raman spectroscopy detection technology,the paper constructed a multifunctional intelligent probe hairpin DNA loop amplification SERS detection method mi RNA-203.The method mainly with multifunctional intelligent hairpin probe type suitable DNA,PCR,restriction and carry Raman signal molecule in the nano Au bio barcode probes as raw material design double circulation amplification mode(i.e.target replacement cycle and polymerase chain replaced by circular),and the amplification effect is remarkably increased.The best reaction conditions obtained under the linear concentration range of this method for the detection of mi RNA-203 1.0 × 10-14~1.0 × 10-7 M,a detection limit of 6.3 f M(S/N=3),the sensitive detection of mi RNA-203.This method is simple,rapid,high sensitivity,good selectivity,provides a new idea and method for surface enhanced Raman detection application in biochemical analysis.