SAW-based hydrogel testing for detecting viruses or other antigens

A system comprising:

• multiple surface acoustic wave (SAW) sensors, each of the multiple SAW sensors comprising:
• a piezoelectric substrate;
• first and second interdigitating transistors over the piezoelectric substrate, the first interdigitating transistor configured to convert an input electrical signal into an acoustic wave, the second interdigitating transistor configured to convert the acoustic wave into an output electrical signal, the piezoelectric substrate configured to transport the acoustic wave;
• and
• a detection layer over the piezoelectric substrate and positioned at least partially between the first and second interdigitating transistors, the detection layer comprising (i) antibodies and (ii) a hydrogel layer over the antibodies;
• wherein the antibodies of at least one of the SAW sensors are configured to bind to one or more biological analytes;
• and
• wherein, in each of the multiple SAW sensors:
• each of the first and second interdigitating transistors comprises multiple conductive fingers;
• and,
• the detection layer extends between and into the first and second interdigitating transistors such that portions of the detection layer are positioned between the multiple conductive fingers in each of the first and second interdigitating transistors.

A method comprising:

• providing a flow of air to one or more surface acoustic wave (SAW) sensors;
• and
• detecting one or more biological analytes in the flow of air using the one or more SAW sensors;
• wherein at least one of the one or more SAW sensors comprises:
• a piezoelectric substrate;
• first and second interdigitating transistors over the piezoelectric substrate, the first interdigitating transistor configured to convert an input electrical signal into an acoustic wave, the second interdigitating transistor configured to convert the acoustic wave into an output electrical signal, the piezoelectric substrate configured to transport, the acoustic wave;
• and
• a detection layer over the piezoelectric substrate and positioned at least partially between the first and second interdigitating transistors, the detection layer comprising (i) antibodies configured to bind to the one or more biological analytes and (ii) a hydrogel layer over the antibodies;
• and
• wherein, in each of the one or more SAW sensors:
• each of the first and second interdigitating transistors comprises multiple conductive fingers;
• and
• the detection layer extends between and into the first and second interdigitating transistors such that portions of the detection layer are positioned between the multiple conductive fingers in each of the first and second interdigitating transistors.