Methods for quantitation of insulin and C-peptide
AssigneeQuest Diagnostics Investments Incorporated
InventorsDov Shiffman, Carmen Tong, James J. Devlin, Michael J. McPhaul
Life of this patent
Estimating the term…
Abstract
Methods are described for diagnosing or prognosing insulin resistance in diabetic and pre-diabetic patients, the method comprising determining the amount of insulin and C-peptide in a sample. Provided herein are mass spectrometric methods for detecting and quantifying insulin and C-peptide in a biological sample utilizing enrichment and/or purification methods coupled with tandem mass spectrometric or high resolution/high accuracy mass spectrometric techniques.
Claims19
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
- RS
- =
- (
- Insulin
- ×
- 0.0265
- )
- +
- (
- C-peptide
- ×
- 0.00511
- )
- +
- (
- Creatinine
- ×
- -3.2641
- )
- P
-
- (
- IR
- )
- =
- e
- -
- 2.2626
- +
- 1.0005
- ×
- RS
- 1
- +
- e
- -
- 2.2626
- +
- 1.0005
- ×
- RS
- .
Dependencies are inferred from the claim text.