US 11,927,537 B2
Rapid, low-cost process for the preparation of SERS substrate and SERS substrate prepared thereby
Amit Asthana, Hyderabad (IN); Mohan Rao Chintalagiri, Hyderabad (IN); Saurabh Kumar Srivastava, Hyderabad (IN); and Gopi Suresh Oggu, Hyderabad (IN)
Assigned to COUNCIL OF SCIENTIFIC & INDUSTRIAL RESEARCH, New Delhi (IN)
Appl. No. 17/256,555
Filed by COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH, New Delhi (IN)
PCT Filed Feb. 8, 2019, PCT No. PCT/IN2019/050102
§ 371(c)(1), (2) Date Dec. 28, 2020,
PCT Pub. No. WO2020/003321, PCT Pub. Date Jan. 2, 2020.
Claims priority of application No. 201811023895 (IN), filed on Jun. 27, 2018.
Prior Publication US 2021/0156804 A1, May 27, 2021
Int. Cl. G01N 21/65 (2006.01); G01N 33/543 (2006.01); B82Y 15/00 (2011.01)
CPC G01N 21/658 (2013.01) [G01N 33/54346 (2013.01); B82Y 15/00 (2013.01)] 17 Claims
OG exemplary drawing
 
1. 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 hydrophilic zone and one or more hydrophobic zones surrounding the hydrophilic zone.