US 11,655,494 B2
Apparatus, systems, and methods for determining the concentration of microorganisms and the susceptibility of microorganisms to anti-infectives based on redox reactions
Oren S. Knopfmacher, San Francisco, CA (US); Meike Herget, Woodside, CA (US); Nitin K. Rajan, Palo Alto, CA (US); and Michael D. Laufer, Menlo Park, CA (US)
Assigned to Avails Medical, Inc., Menlo Park, CA (US)
Filed by Avails Medical, Inc., Menlo Park, CA (US)
Filed on Mar. 10, 2020, as Appl. No. 16/814,153.
Application 16/814,153 is a continuation of application No. PCT/US2018/054003, filed on Oct. 2, 2018.
Claims priority of provisional application 62/567,648, filed on Oct. 3, 2017.
Prior Publication US 2020/0224241 A1, Jul. 16, 2020
Int. Cl. C12Q 1/18 (2006.01); C12Q 1/06 (2006.01); G01N 27/416 (2006.01)
CPC C12Q 1/18 (2013.01) [C12Q 1/06 (2013.01); G01N 27/4168 (2013.01)] 14 Claims
 
1. A method of determining a concentration of an infectious agent, the method comprising:
diluting a sample comprising the infectious agent with a dilutive solution to yield a diluted sample;
introducing the diluted sample to a sensor such that the diluted sample is in fluid communication with a redox-active material of the sensor, wherein the redox-active material comprises a gold layer, a platinum layer, a metal oxide layer, or a combination thereof, wherein the sensor comprises an active electrode and a reference electrode, the active electrode comprising a redox-active layer positioned on top of at least one conductive metallic layer; and
monitoring a decrease in an oxidation reduction potential (ORP) of the diluted sample over a period of time using at least one parameter analyzer coupled to the sensor to determine the concentration of the infectious agent in the sample, wherein the ORP is monitored in the absence of any added reporter molecules in the diluted sample.