Construction Of Resonance Raman/infrared Absorption And Resonance Raman/Fluorescence Dual-Mode Bioprobes

For II-VI semiconductor materials,resonance Raman scattering is mainly caused by the lattice multi phonon resonance of semiconductor materials,characterized by narrow half peak width and clear fingerprint.As the output signal of optical probe,it has emerged in the field of biological detection.However,single-mode optical probe,with the increasing requirement for accuracy,sensitivity and range of detection in clinical diagnosis,has been limited in practical application.The dual-mode optical probe,through which the signals can be verified and supplemented each other,can effectively address this problem.Therefore,in this paper,taking zinc based semiconductor as the research object,the resonance Raman scattering/infrared absorption dual-mode optical probe is constructed based on ZnO@SiO₂ and the resonance Raman scattering/fluorescence dual-mode optical probe is constructed based on ZnS: Mn²⁺,thus breaking through the bottlenecks of the existing single-mode optical probe,such as inadequate information,insufficient accuracy of detection results,narrow linear range and so on,and laying the foundation for promoting the design and application of the dual-mode optical probes.The main research contents are as follows:?1?The ZnO@SiO₂ dual-mode optical probe was constructed.Resonance Raman scattering and infrared absorption with strong anti-interference ability were used as dual-readout signals for the first time to detect carcinoembryonic antigen.There is no mutual interference between the multi phonon resonance Raman scattering signal derived from ZnO and the characteristic infrared fingerprint signal of the transverse and longitudinal optical phonon modes with asymmetric stretching of the Si-O-Si bonds derived from SiO₂,thus ensuring the accuracy of detection.The detection limit and the linear range were found out to be 98 fg/mL and 50 fg/mL-500 ng/mL.Better accuracy,sensitivity and linear range can be achieved through the dual-mode optical probe than the single-mode optical probes,significantly exceeding the detection performance of current commercial kits.?2?In order to further optimize the design of the probe and improve the performance of the probe,ZnS: Mn²⁺prepared with hydrothermal method was employed as the probe material to construct a resonance Raman scattering/fluorescence dual-mode optical probe.The band gap of ZnS,compared with ZnO,is more matched with the energy of 325 nm laser,with stronger multi phonon resonance Raman scattering signal of ZnS.Moreover,the doping of Mn²⁺help not only introduce the fluorescence emission signal from d electron ⁴T₁-⁶A₁ transition,but also reduce the intrinsic fluorescence emission of ZnS,weakening the background fluorescence interference of resonance Raman scattering signal,and improving the accuracy of detection.Through this dual-mode optical probe,in the detection,ultrasensitivity can reach 113 ag/mL and ultra-wide linear range can span 9 orders of magnitude?100 ag/mL-200 ng/mL?.In addition,the dual-mode optical probe showed a good detection effect on the actual serum samples,thus proving its application prospect in clinical diagnosis.