title: Preparation and application of a novel molecularly imprinted solid-phase microextraction monolith for selective enrichment of cholecystokinin neuropeptides in human cerebrospinal fluid.
abstract: A novel molecularly imprinted polymer (MIP) monolith for highly selective extraction of cholecystokinin (CCK) neuropeptides was prepared in a micropipette tip. The MIPs were synthesized by epitope imprinting technique and the polymerization conditions were investigated and optimized. The synthesized MIPs were characterized by infrared spectroscopy, elemental analyzer and scanning electron microscope. A molecularly imprinted solid-phase microextraction (MI-μ-SPE) method was developed for the extraction of CCK neuropeptides in aqueous solutions. The parameters affecting MI-μ-SPE were optimized. The results indicated that this MIP monolith exhibited specific recognition capability and high enrichment efficiency for CCK neuropeptides. In addition, it showed excellent reusability. This MIP monolith was used for desalting and enrichment of CCK4, CCK5 and CCK8 from human cerebrospinal fluid prior to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis, and the results show that this MIP monolith can be a useful tool for effective purification and highly selective enrichment of multiple homologous CCK neuropeptides in cerebrospinal fluid simultaneously. By employing MI-μ-SPE combined with HPLC-ESI-MS/MS analysis, endogenous CCK4 in human cerebrospinal fluid was quantified.
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Ji
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D002766:Cholecystokinin / Q000134:cerebrospinal fluid* / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006801:Humans; D057230:Limit of Detection; D054802:Molecular Imprinting / Q000379:methods; D009479:Neuropeptides / Q000134:cerebrospinal fluid / Q000302:isolation & purification; D011108:Polymers / Q000737:chemistry; D052617:Solid Phase Microextraction / Q000379:methods*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D009479:Neuropeptides; D011108:Polymers; D002766:Cholecystokinin
keywords: cholecystokinin; epitope approach; molecularly imprinted polymer monolith; solid-phase microextraction