	US 12,332,236 B2
	Methods for quantitation of insulin and C-peptide
Dov Shiffman, Palo Alto, CA (US); Carmen Tong, Dublin, CA (US); James J. Devlin, Lafayette, CA (US); and Michael J. McPhaul, Capistrano Beach, CA (US)
Assigned to Quest Diagnostics Investments LLC, Secaucus, NJ (US)
Filed by Quest Diagnostics Investments LLC, Secaucus, NJ (US)
Filed on May 20, 2024, as Appl. No. 18/669,323.
Application 18/669,323 is a continuation of application No. 17/234,448, filed on Apr. 19, 2021, granted, now 12,025,610.
Application 17/234,448 is a continuation of application No. 15/942,188, filed on Mar. 30, 2018, granted, now 10,983,108.
Claims priority of provisional application 62/644,378, filed on Mar. 16, 2018.
Claims priority of provisional application 62/480,029, filed on Mar. 31, 2017.
Prior Publication US 2024/0393317 A1, Nov. 28, 2024
Int. Cl. G01N 33/49 (2006.01); G01N 30/72 (2006.01); G01N 33/68 (2006.01); G01N 33/74 (2006.01)

CPC G01N 33/492 (2013.01) [G01N 30/7266 (2013.01); G01N 33/6848 (2013.01); G01N 33/74 (2013.01); G01N 2333/62 (2013.01); G01N 2800/042 (2013.01); G01N 2800/50 (2013.01)]

19 Claims

1. A method for measuring insulin resistance in diabetic or pre-diabetic patients by mass spectrometry, the method comprising:

purifying a sample comprising insulin and C-peptide by liquid chromatography;

ionizing the insulin and the C-peptide by an ionization source under conditions suitable to generate one or more insulin and C-peptide ions detectable by mass spectrometry;

measuring creatinine levels;

determining an amount of the one or more insulin and C-peptide ions by mass spectrometry;

determining an amount of the insulin and the C-peptide in the sample from the amount of the one or more insulin and C-peptide ions; and

determining an insulin resistance score (RS) and/or a probability of developing insulin resistance (P(IR)) from the amount of the insulin and the C-peptide and the creatinine levels in the sample, wherein insulin resistance in diabetic or pre-diabetic patients is measured from the RS and/or the P(IR);

wherein