US 12,405,253 B2
Methods and systems for hydrophilic-phase extraction
Robert MacNeill, Monroe Township, NJ (US)
Assigned to Laboratory Corporation of America Holdings, Burlington, NC (US)
Filed by Laboratory Corporation of America Holdings, Burlington, NC (US)
Filed on Dec. 30, 2022, as Appl. No. 18/148,839.
Claims priority of provisional application 63/295,585, filed on Dec. 31, 2021.
Prior Publication US 2023/0213490 A1, Jul. 6, 2023
Int. Cl. G01N 30/72 (2006.01); B01D 15/30 (2006.01); B01D 15/42 (2006.01); G01N 30/00 (2006.01); G01N 30/14 (2006.01); G01N 30/88 (2006.01); G01N 30/02 (2006.01)
CPC G01N 30/7233 (2013.01) [B01D 15/305 (2013.01); B01D 15/424 (2013.01); G01N 30/14 (2013.01); G01N 30/88 (2013.01); G01N 2030/009 (2013.01); G01N 2030/027 (2013.01); G01N 2030/8827 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A method for determining an amount and/or presence of a compound of interest in a sample from a subject comprising the steps of:
providing a sample believed to contain the compound of interest, wherein the sample is a biological sample, and wherein the compound of interest is an RNA or a DNA oligonucleotide;
conducting an extraction of the compound of interest, wherein the extraction is a hydrophilic-phase extraction conducted on a sorbent bed comprising an aminopropyl phase on a silica base, and wherein conducting the hydrophilic-phase extraction comprises
(a) adding an aqueous acid and an internal standard to the sample;
(b) conditioning the sorbent bed with a solution comprising 9:1 v:v acetonitrile: 2.0% formic acid;
(c) loading the sample onto the sorbent bed;
(d) washing the sorbent bed; and
(e) eluting the compound of interest with a solution comprising ammonium hydroxide and acetonitrile;
isolating the compound of interest from other components of the sample via liquid chromatography; and
analyzing the compound of interest via a mass spectrometer.