High performance liquid chromatographic measurement of lignocaine in tissue samples following transabdominal placental biopsy.
A method is described for the measurement of lignocaine in small samples of fetal and placental tissue. Tissue samples (ca 100 mg) are digested using a preteolytic enzyme. Lignocaine and an internal standard are extracted into methyl tert-butyl ether and analysed by high-performance liquid chromatography with electrochemical detection (+1.0 V vs Ag/AgCl). The limit of accurate measurement is better than 0.1 mg/kg wet weight for a 100 mg sample. This method has been used to assess fetal exposure to the drug when used as a local anaesthetic during transabdominal placental biopsy (chorionic villus sampling). The range of lignocaine concentrations found in the tissue samples was large (from less than 0.04 mg/kg wet weight to 15.4 mg/kg wet weight) although most samples contained less than 1.0 mg lignocaine/kg wet weight.
Monkman
S C
SC
Poisons Unit, Guy's Hospital, London, UK.
Armstrong
R
R
Flanagan
R J
RJ
Holt
D W
DW
Rosevear
S
S
D000818:Animals; D001706:Biopsy; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004563:Electrochemistry; D005260:Female; D005333:Fetus / Q000378:metabolism; D006801:Humans; D008012:Lidocaine / Q000032:analysis* / Q000097:blood; D010920:Placenta / Q000032:analysis*; D011247:Pregnancy
D008012:Lidocaine