Patent ID: 11927537
Assignee: COUNCIL OF SCIENTIFIC & INDUSTRIAL RESEARCH
Field: Measurement (Instruments)
Classification: CPC G  B | IPC B  G

Claim 11:
12. A process for preparing a SERS substrate comprising:
[a] providing a paper-based substrate having a top surface and a bottom surface;
[b] applying reactants comprising a chitosan solution and a metallic precursor solution on the top surface of the substrate of step [a]; and
[c] incubating the substrate of step [b] under saturated humidity at a temperature in the range of 40 to 120° C. for a period in the range of 15 to 60 mins, whereby said incubation results in direct in situ reduction of the metallic precursor by the chitosan to produce metal nanoparticles deposited on the top surface of the substrate,
wherein the top surface of the paper-based substrate comprises a plurality of hydrophilic zones and a plurality of hydrophobic zones, where each of the plurality of hydrophilic zones are separated from each other by one or more of the plurality of hydrophobic zones.