	US 12,487,214 B2
	Pathogen surrogates based on encapsulated tagged DNA for verification of sanitation and wash water systems for fresh produce
Antonios Zografos, Oakland, CA (US); George Roy Farquar, Livermore, CA (US); and John Mark Carter, Livermore, CA (US)
Assigned to SafeTraces, Inc., Pleasanton, CA (US)
Filed by SafeTraces, Inc., Pleasanton, CA (US)
Filed on Feb. 26, 2021, as Appl. No. 17/249,319.
Application 17/249,319 is a division of application No. 15/053,731, filed on Feb. 25, 2016, granted, now 10,962,512.
Claims priority of provisional application 62/200,456, filed on Aug. 3, 2015.
Prior Publication US 2021/0181169 A1, Jun. 17, 2021
Int. Cl. G01N 31/22 (2006.01); A61L 2/28 (2006.01); C07H 21/04 (2006.01); C07K 14/78 (2006.01); G01N 33/02 (2006.01); C12Q 1/6844 (2018.01)

CPC G01N 31/226 (2013.01) [A61L 2/28 (2013.01); C07H 21/04 (2013.01); C07K 14/78 (2013.01); G01N 33/025 (2013.01); C12Q 1/6844 (2013.01); C12Q 2563/185 (2013.01)]

12 Claims

1. A method of providing a pathogen surrogate, comprising:

receiving a poly(lactic-co-glycolic acid)-based carrier formed of a non-toxic substance combining a DNA bar code with the carrier to form a pathogen surrogate; and

performing a benchmarking operation to determine whether a degradation rate of the pathogen surrogate behaves similarly to a degradation rate of a first pathogen when subjected to a first sanitation operation, the benchmarking operation including:

a) applying an amount of the pathogen surrogate to a surface, wherein the amount of the pathogen surrogate comprises a DNA tracer signal from the DNA bar code;

b) subsequently performing the first sanitation operation on the surface;

c) subsequently enumerating a remaining amount of the pathogen surrogate on the surface by measuring a remaining DNA tracer signal;

d) determining a degree of degradation of the pathogen surrogate when subjected to the first sanitation operation from a comparison of the amount of the pathogen surrogate remaining on the surface to the amount of the pathogen surrogate applied to the surface; and

e) comparing the degree of degradation of the pathogen surrogate when subjected to the first sanitation operation to a degree of degradation of the first pathogen when subjected to the first sanitation operation.