Construction Of The Redox Sensitive SERS-probes And Their Evaluation

Surface-enhanced Raman scattering(SERS)has been widely used for biological detection,characterization,imaging and real-time monitoring due to its non-destructive,rapid and sensitive properties.However,the traditional SERS can not detect the deeper layers under the epidermis.In response to this problem,in this paper,two physiological indicators(redox state and pH)were choosed,and the SERS application can be gradually realized from the biological sample surface to subcutaneous,and finally to the deep tissue testing.The details are as follows:1.The gold nanoshells were prepared by using typical approach firstly.Then the redox probe and pH-sensitive probe were constructed via traditional probe construction method,by attaching anthraquinone and 4-mercaptobenzoic acid onto the surface of gold nano-shells.The ratio of the characteristic peak intensity in the SERS spectra of the redox-sensitive probes and the pH-sensitive probes were quantified.The two probes were dropped onto the fresh incision of the fruits or vegetables to determine the redox state of fruits or vegetables.2.The redox-sensitive SERS probes were modified on the surface of the chitosan membrane as a redox-sensitive wound dressing.Based on the wound dressing and the redox state sensor,the SERS probe on an acute wound-covered redox-sensitive wound dressing interacts with the wound tissue fluid.The redox states of the healing wounds were obtained over time by SERS spectroscopy of the SERS probes collected in situ and non-invasively.3.The both SERS probes were modified in the grooves of the acupuncture needles etched with double grooves.Once the dual-functionalized acupuncture needles were inserted into different parts and tissues of animals,the reaction began.The SERS spectra of these probes were collected to obtain redox status and pH changes after the needles pulled out.