Comparison of extraction of a beta-blocker from plasma onto a molecularly imprinted polymer with liquid-liquid extraction and solid phase extraction methods.
An optimised solid phase extraction (SPE) method developed for the extraction of a structural analogue of the beta-blocking drug propranolol from plasma utilising a molecularly imprinted polymer (MIP) has been compared with methods based on conventional liquid-liquid extraction (LLE), and SPE using C18-bonded and immobilised phenyl boronic acid (PBA). All four methods could be used for the extraction of the analyte with acceptable accuracy and precision. The MIP-based method, unlike the other methods required a protein precipitation step prior to extraction to eliminate the effects of co-extracted protein. The best performance was seen with the LLE method followed by SPE on the C18 phase. The MIP-based method represented no advantage over the comparator methods for this analyte. Indeed the performance of the MIP-based method was marginally worse as leaching of low level template impurities prevented detection of the target analyte at low concentrations (5 ngmL(-1)). This relatively poorer performance was evident as worse accuracy at low concentrations with a consequent higher limit of quantification than the conventional methods.
Martin
P D
PD
Department of Drug Metabolism and Pharmacokinetics, AstraZeneca Pharmaceuticals, Mereside, Alderley Park, Macclesfield, Cheshire SK10 4TG, UK. paul.martin@astrazeneca.com
Jones
G R
GR
Stringer
F
F
Wilson
I D
ID
D000319:Adrenergic beta-Antagonists / Q000097:blood*; D000605:Amino Alcohols / Q000097:blood; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D015394:Molecular Structure; D009281:Naphthalenes / Q000097:blood; D011108:Polymers / Q000737:chemistry*; D011433:Propranolol / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012997:Solvents
D000319:Adrenergic beta-Antagonists; D000605:Amino Alcohols; C496830:M 45655; C496831:M 47070; D009281:Naphthalenes; D011108:Polymers; D012997:Solvents; D011433:Propranolol