US 12,422,415 B2
Analytical methods of assessing cytisine purity
Curtis Swift, Stockton (GB); Katie Williams, Seaham (GB); Nigel Richardson, Stevenage (GB); and Marco Delgado, Cucks (GB)
Assigned to Achieve Life Sciences, Inc.
Filed by Achieve Life Sciences, Inc., Bothell, WA (US)
Filed on Sep. 7, 2022, as Appl. No. 17/939,218.
Claims priority of provisional application 63/241,829, filed on Sep. 8, 2021.
Prior Publication US 2023/0090994 A1, Mar. 23, 2023
Int. Cl. G01N 30/34 (2006.01); G01N 30/24 (2006.01); G01N 30/72 (2006.01); G01N 30/02 (2006.01); G01N 30/04 (2006.01)
CPC G01N 30/34 (2013.01) [G01N 30/24 (2013.01); G01N 30/72 (2013.01); G01N 2030/027 (2013.01); G01N 2030/042 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A chromatographic method of assessing purity of cytisine, the method comprising:
(a) introducing a cytisine sample to a column comprising a stationary phase including stearic acid and having a length of 150 mm, an inner diameter of 4.6 mm, and a particle size of 2.5 μm, wherein the cytisine sample comprises one or more impurities;
(b) applying a first mobile phase having a pH of about 10 to the column such that cytisine and the one or more impurities are retained on said column;
(c) eluting cytisine and the one or more impurities by applying a second mobile phase having a pH of about 10 to said column; and
(d) detecting cytisine and the one or more impurities in the second mobile phase.