US 12,461,037 B1
Hydrophobic copper thin film for surface plasmon resonance-based sensor
Mohammad Kamal Hossain, Dhahran (SA)
Assigned to King Fahd University of Petroleum and Minerals, Dhahran (SA)
Filed by King Fahd University of Petroleum and Minerals, Dhahran (SA)
Filed on Jun. 18, 2025, as Appl. No. 19/242,430.
Claims priority of provisional application 63/796,647, filed on Apr. 29, 2025.
Int. Cl. G01N 21/77 (2006.01); B01L 3/00 (2006.01); G01N 21/41 (2006.01); G01N 21/552 (2014.01); G01N 33/543 (2006.01)
CPC G01N 21/77 (2013.01) [B01L 3/502 (2013.01); B01L 3/5027 (2013.01); B01L 3/502715 (2013.01); G01N 21/41 (2013.01); G01N 21/553 (2013.01); G01N 21/554 (2013.01); G01N 33/54373 (2013.01); G01N 2021/7776 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A surface plasmon resonance sensor system, comprising:
a sensor plate having a first side and a second side, wherein the second side is opposite the first side, wherein the sensor plate includes:
a quartz glass substrate, and
an annealed cuprous oxide film formed by sputtering a copper film onto the quartz glass substrate then annealing the copper film at a temperature of from about 400° C. to about 600° C. for about two hours to convert the copper film to the annealed cuprous oxide film having a refractive index of about 3.05 to about 3.11, an energy band gap Eg of 1.54 to 1.69 eV and a surface with a wetting contact angle of 42.3° to 85.2°;
a quartz prism having a base surface attached to the first side of sensor plate against the quartz glass substrate;
a microfluidics unit attached to the second side of the sensor plate against the annealed cuprous oxide film, wherein the microfluidics unit includes a fluid reservoir having an inlet port and an outlet port, wherein the fluid reservoir contains a carrier fluid;
a target analyte reservoir containing a target analyte;
a pump connected between the target analyte reservoir and the inlet port, wherein the pump is configured to inject the target analyte into the microfluidics unit through the inlet port;
a binder attached to the annealed cuprous oxide film, wherein the binder is configured to attach to the target analyte;
a laser configured to transmit a laser beam into a face of the quartz prism at an incident angle configured to generate surface plasmons which resonate with the annealed cuprous oxide film and reflect a phase shifted laser beam from the annealed cuprous oxide film;
receive optics configured to receive the phase shifted laser beam;
a charge coupled device coupled to the receive optics, wherein the charge coupled device is configured to convert the phase shifted laser beam to an electrical signal; and
a computing unit including an electrical circuitry, a memory storing program instructions and at least one processor configured to execute the program instructions, wherein the computing unit is configured to receive the electrical signal and compute a refractive index based on the phase shift, wherein a change in the refractive index is configured to indicate detection of the target analyte.