Enantioseparation of nicotine alkaloids in cigarettes by CE using sulfated β‐CD as a chiral selector and a capillary coated with amino groups

Abstract

Nicotine (NC) and its related compounds (cotinine (CN), nornicotine (NN), anatabine (AT) and anabasine (AB)) were simultaneously enantioseparated by CE using a capillary with amino groups and sulfated beta-CD as a chiral selector. The optimum running conditions were found to be 30 mM acetate buffer (pH 5.0) containing 8% sulfated beta-CD with an applied voltage of +15 kV at 30 degrees C using direct detection at 260 nm. Using a capillary coated with amino groups, the EOF migrates toward the positive pole. However, when sulfated beta-CD was added to the BGE, it was found that the EOF migrated toward the negative pole due to ionic adsorption of sulfated beta-CD to amino groups on the capillary inner wall. All the cationic analytes migrated as anions, suggesting that they formed stable anionic complexes with sulfated beta-CD. With this system and a simple pretreatment with mini-cartridges, NC alkaloids in five cigarette samples were enantioseparated. As a result, each of the compounds except for CN was detected. In the case of NC, only (S)-NC was detected (more than 99.9%), but in the case of NN, AT and AB, the ratios of (S)-isomer to total isomers were in the ranges 58-70, 81-85 and 59-65%, respectively. On the other hand, only NC was detected in cigarette smoke and the ratio of (S)- and (R)-NCs was 96:4. The amounts of NC alkaloids in cigarettes suggest that the production of (R)-NC resulted from racemization due to the high temperature/burning of the cigarette.

On the Relation between the Interfacial Charge of a Discharging Nozzle and Electrification of a Liquid Microjet

“…5 potentials of liquid microjets of aqueous NaI solutions using a chemically-modified fused silica capillary (GL Science FunCap-CE/Type A). 6,7 This capillary has an amino group chemically bonded to a silanol (SiOH) group on a fused silica surface, so that · surf þ · ad is always positive at pH ¼7 regardless of the concentration of NaI. After confirmation of the relation between μ and · surf þ · ad , we present a model that explains the reversal of a surface potential of a liquid microjet with the concentration of Na…”

Analysis of Phosphorus-containing Amino Acid-type Herbicides by Capillary Electrophoresis/Mass Spectrometry Using a Chemically Modified Capillary Having Amino Groups

“…RSDs of migration time were 0.36-0.52%, which were from 1/8 to 1/2 of the values obtained using untreated fused-silica capillaries. 18,19) The limits of detection (LODs), defined as a signal-to-noise ratio was 3 in extracted ion pherogram, were 0.5-10 µg/ml. When LODs in GC/MS methods were defined to be full-mass spectra measured, the LODs obtained using the proposed CE/MS method were 1/1000 (BIAL) -1 (AMPA) of the values obtained with N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide derivatization, 2) although the values were higher than those obtained by GC/MS method (selected ion monitoring) with O-methyl, N-acetyl derivatization.…”

“…A chemically modified capillary having amino groups (amino capillary) has a positively charged inner wall under acidic conditions. 19) When the amino capillary is used with an acidic BGE in negative-polarity mode, both anionic phosphorus-containing amino acid-type herbicides and EOF move toward the MS detector. Because an amino capillary gives much more reproducible migration times, 19) we thought it would be a good choice for developing a rapid and reproducible analysis of phosphorus-containing amino acid-type herbicides.…”

“…19) When the amino capillary is used with an acidic BGE in negative-polarity mode, both anionic phosphorus-containing amino acid-type herbicides and EOF move toward the MS detector. Because an amino capillary gives much more reproducible migration times, 19) we thought it would be a good choice for developing a rapid and reproducible analysis of phosphorus-containing amino acid-type herbicides. In this report, we describe a simple and practical CE/MS method for analysis of phosphorus-containing amino acid-type herbicides using an amino capillary.…”

Fast and sample cleanup-free measurement of nicotine and cotinine by stable isotope dilution ultra-performance liquid chromatography–tandem mass spectrometry

“…Several methods, such as enzyme-linked immunosorbent assays [9][10][11], capillary electrophoresis methods [12], and LC-MS/MS methods [7,[13][14][15][16][17][18][19][20][21][22][23], have been described for the measurement of nicotine and cotinine in human body fluids. A high specificity was reached with the MS/MS technology, but most methods required labor-intensive sample preparations or time-consuming measurements.…”