Detection Of SO₂/Sulfite And Biomarkers Based On SERS Technology

The surface enhanced Raman spectroscopy(SERS)has been widely used in food and drug monitoring and biological testing thanks to its high spectral resolution,non-destructive testing,weak optical bleaching effects and good transparency in biological environments.On the basis of SERS technique combining with the ability of specific recognition of the affinity peptide,we realized sensitive detection of SO₂/sulfite in food and drinks.We further explored the detection performance of the frequency shift method on biomarkers.The main research was as follows:(1)Utilizing the specific binding between SO₂ and tertiary amino group,we developed an ultra-sensitive detection method of residual SO₂/sulfite in food and drinks which is fast and reliable.The limit of detection of this method is 1?M.This method doesn't require complex pretreatment process for detecting samples.Worthy of note is that the reaction condition is mild.These advantages increase the potential for this sensing platform to develop into a rapid detection kit.(2)On the basic of the study on the relationship between the length of double strand DNA sequence with the change of frequency shift values,we designed the sequence of DNA to further explore the influence of mismatch number(1-5 mismatch sites)and the distance between mismatch sites(1-12 bases)to the Raman frequency shift values.By analyzing the shifts in the Raman spectrum of the reporter before and after introducing the target DNA,we aim to reveal more about the mechanisms of the vibration in the chemical bonds.(3)Utilizing the specific hydrolysis ability of trypsin combining the specific binding performance of affinity peptide.The detection limit of 4 nm and 10 PM for trypsin and spike protein from COVID-19 respectively,was achieved.The preliminary results showed that this method has certain performance in different sensing systems.