. Author manuscript; available in PMC: 2011 Jun 1.

Published in final edited form as: J Chromatogr B Analyt Technol Biomed Life Sci. 2010 Apr 3;878(19):1493–1498. doi: 10.1016/j.jchromb.2010.03.047

Table 4.

evaluation of the absolute matrix effect (ME) of the mean peak area (mpa) of adenosine and the internal standard (IS). The matrix effect (ME) is expressed as the ratio of the mpa of set 2 (standard line in medium) to the mpa of set 1 (standard line in the mobile phase) multiplied by 100. A value of >100% indicates ionization enhancement, a value of <100% indicates ionization suppression.

Concentration adenosine (ng/ml)	mpa adenosine		ME adenosine (B₁/A₁%)	mpa IS		ME IS (B₂/A₂%)
Concentration adenosine (ng/ml)	Set 1 (mobile phase)	Set 2 (medium)	ME adenosine (B₁/A₁%)	Set 1 (mobile phase)	Set 2 (medium)	ME IS (B₂/A₂%)
15.6	4240	7140	168	150000	62900	42
31.2	4700	8660	184	145000	63000	43
125	33800	58300	172	151000	65200	43
500	143000	231000	162	154000	62700	41
1000	293000	461000	157	163000	62600	38
	A₁	B₁		A₂	B₂