Detection of ketamine and its metabolites in human hair using an integrated nanoflow liquid chromatography column and electrospray emitter fritted with a single porous 10 μm bead

TY - JOUR

T1 - Detection of ketamine and its metabolites in human hair using an integrated nanoflow liquid chromatography column and electrospray emitter fritted with a single porous 10 μm bead

AU - Parkin, Mark C.

AU - Longmoore, Alana M.

AU - Turfus, Sophie C.

AU - Braithwaite, Robin A.

AU - Cowan, David A.

AU - Elliott, Simon

AU - Kicman, Andrew T.

PY - 2013/2/15

Y1 - 2013/2/15

N2 - Targeting metabolites incorporated into hair following drug administration is useful for evidential purposes as this approach can aid in differentiating between administration and passive exposure. Greater analytical sensitivity is required than for targeting the parent drug alone. A 20 mu m i.d. fused silica capillary column with an integrated electrospray emitter fritted with a single porous 10 mu m polymeric bead has been successfully fabricated to facilitate this purpose. The sensitivity gains through the use of these integrated single fritted columns coupled to a nanoelectrospray source (nanoflow-LC nanoESI) over conventional liquid chromatography-tandem mass spectrometry (LC-MS/MS) columns was explored by their application to the detection of ketamine and its phase I metabolites in human hair. Hair was collected from 4 volunteers following the administration of a small oral dose of ketamine (50 mg) and subsequently analysed by the capillary-LC nanoESI approach. The drug and its metabolites were extracted from hair using solid phase extraction following a methanolic wash, pulverisation with a ball mill and acid digestion. From a 50 mu L extract, 1 mu L was injected and the method provided a limit of detection estimated to be 5 fg on column for ketamine and norketamine and 10 fg for dehydronorketamine. The single porous fit minimises extra column band broadening and offers an alternative fitting approach which reduces the blocking of the electrospray emitter, in comparison with other approaches such as sintering and polymerisation. (C) 2012 Elsevier B.V. All rights reserved.

AB - Targeting metabolites incorporated into hair following drug administration is useful for evidential purposes as this approach can aid in differentiating between administration and passive exposure. Greater analytical sensitivity is required than for targeting the parent drug alone. A 20 mu m i.d. fused silica capillary column with an integrated electrospray emitter fritted with a single porous 10 mu m polymeric bead has been successfully fabricated to facilitate this purpose. The sensitivity gains through the use of these integrated single fritted columns coupled to a nanoelectrospray source (nanoflow-LC nanoESI) over conventional liquid chromatography-tandem mass spectrometry (LC-MS/MS) columns was explored by their application to the detection of ketamine and its phase I metabolites in human hair. Hair was collected from 4 volunteers following the administration of a small oral dose of ketamine (50 mg) and subsequently analysed by the capillary-LC nanoESI approach. The drug and its metabolites were extracted from hair using solid phase extraction following a methanolic wash, pulverisation with a ball mill and acid digestion. From a 50 mu L extract, 1 mu L was injected and the method provided a limit of detection estimated to be 5 fg on column for ketamine and norketamine and 10 fg for dehydronorketamine. The single porous fit minimises extra column band broadening and offers an alternative fitting approach which reduces the blocking of the electrospray emitter, in comparison with other approaches such as sintering and polymerisation. (C) 2012 Elsevier B.V. All rights reserved.

KW - Nano-electrospray

KW - Nanoflow liquid chromatography

KW - Hair analysis

KW - Ketamine

KW - SIMULTANEOUS QUANTITATIVE-DETERMINATION

KW - MASS-SPECTROMETRY

KW - ABUSE

KW - DRUGS

KW - COCAINE

KW - OPIATES

KW - LC

KW - AMPHETAMINES

KW - NORKETAMINE

KW - DISPOSITION

U2 - 10.1016/j.chroma.2012.12.019

DO - 10.1016/j.chroma.2012.12.019

M3 - Article

SN - 0021-9673

VL - 1277

SP - 1

EP - 6

JO - Journal of Chromatography A

JF - Journal of Chromatography A

ER -