PubMed · 3452059
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
1987-06-10. Codeine and homebake.. https://pubmed.ncbi.nlm.nih.gov/3452059/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Explore the source record for details and available documents.
Electrospray ionization (ESI) is the most widely used ionization method in on-line coupling of capillary electrophoresis-mass spectrometry (CE-MS). The conventional coaxial sheath flow electrospray interface is currently being replaced by the more sensitive nanoelectrospray technique. The usual limitation of nanoelectrospray CE-MS interface has been its short lifetime caused by deterioration of the metal coating on the CE capillary terminus. This article describes an easy way to construct a more durable and sensitive nanospray interface for nonaqueous CE-MS. In this approach a very thin glass spray capillary (ca. 30 microm outer diameter) is partly inserted inside the CE capillary, the junction being surrounded by the electrolyte medium, which is in contact with the platinum electrode. The interface was tested with five pharmaceuticals: methadone, pentazocine, levorphanol, dihydrocodeine, and morphine. Detection limits ranged from 12 to 540 fmol. Separation efficiency and reproducibility were also studied. The CE current was found to be stable and the migration times were highly reproducible. All the CE separations were carried out in a nonaqueous background electrolyte solution.
Opiates are commonly abused substances, and forensic urine drug-testing for them requires gas chromatographic-mass spectrometric (GC-MS) confirmation. There are also medical reasons to test urine for opiates, and confirmation procedures other than GC-MS are often used for medical drug-testing. A thin-layer chromatographic (TLC) method distinguishes morphine, acetylmorphine, hydromorphone, oxymorphone, codeine, dihydrocodeine, hydrocodone, and oxycodone in clinical specimens. In certain clinical circumstances, GC-MS confirmation is requested for opiates identified by TLC, but, to our knowledge, no previous report examines all of the above opiates in a single GC-MS procedure. We find that they can be distinguished by GC-MS analyses of trimethylsilyl (TMS) ether derivatives, and identities of 6-keto opiates can be further confirmed by GC-MS analysis of methoxime (MO)-TMS derivatives. Inclusion of deuterium-labeled internal standards permits identification of the opiates in urine at concentrations below the TLC cutoff level of 600 ng/ml, and the GC-MS assay is linear over a concentration range that spans that level. This GC-MS procedure has proved useful as a third-stage identification step in a medical drug-testing sequence involving prior immunoassay and TLC.