Case Report, J Forensic Toxicol Pharmacol Vol: 10 Issue: 4
Quantitative Determination of Tetramethylammonium in Blood and Urine Samples by Liquid Chromatography-Tandem Mass Spectrometry
Jegal Hyeon, Sineun Kim, Jiyeong Jo, Heesang Lee and Meejung Park
Forensic Toxicology and Chemistry Division, Busan Institute of National Forensic Service, Yangsan 50612, Republic of Korea
*Corresponding author: Meejung Park, Forensic Toxicology and Chemistry Division, Busan Institute of National Forensic Service, Yangsan 50612, Republic of Korea, Tel: +82-55-380-4110, Fax: +82-55-380-4114, E-mail: meejung@korea.kr
Received date: May 16, 2021; Accepted date: June 04, 2021; Published date: June 11, 2021
Abstract
Tetramethylammonium (tetramine), a highly toxic compound, is found in high levels in the salivary glands of the sea snail, Neptunea. Tetramine neurotoxicity is fatal, and therefore, prompt determination of tetramine in patients’ biological samples is important in guiding proper and timely treatment. However, there are only a few reports on the quantitative determination of tetramine in human’s biological samples. In the present study, we developed a liquid chromatographytandem mass spectrometry (LC-MS/MS) method with simple protein precipitation for sample extraction. Using the method, we performed a quantitative determination of tetramine in blood and urine samples of a couple who were transferred to a hospital emergency room mentioned after consuming Neptunea. The validation parameters including linearity, accuracy, precision, matrix effect, and recovery were satisfactory. The concentrations of tetramine in the husband’s femoral vein blood and urine were 1.37 mg/L and 15.07 mg/L, respectively, and 0.57 mg/L and 5.85 mg/L, in the wife’s blood and urine, respectively. Since few studies have reported toxic and fatal levels of tetramine in blood, this study can be a reference to evaluate tetramine poisoning in the clinical and postmortem toxicology.
Keywords: Tetramethylammonium (Tetramine), LC-MS/MS,Blood,Urine,Hospital emergency room
Introduction
Tetramine is a highly toxic compound, found in high levels in the salivary glands of some gastropods such as Neptunea arthritica and Neptunea intersculpta [1]. Which are commonly found at the South Korean coast. It is known to be a potent neurotoxin owing to its chemical structure. The chemical structure of tetramine contains quaternary ammonium, and is similar to acetylcholine. The neurotoxicity of tetramine may be due to binding and activating nicotinic-acetylcholine receptors causing difficulties in breathing, muscular paralysis, and possible death [1]. Other symptoms of tetramine poisoning include dizziness, blurred vision, bilateral leg weakness, and gait disturbance [2]. In South Korea, several cases of tetramine poisoning associated with the consumption of Neptunea, have been reported [2-5]. Tetramine neurotoxicity is fatal, and therefore, prompt determination of tetramine in patients’ biological samples is important in guiding proper and timely treatment. However, there are only a few reports on the quantitative determination of tetramine in the patients’ biological samples. Tetramine has low molecular weight and high polarity, therefore, Gas Chromatography/ Mass Spectrometry (GC/MS) is not an efficient method for quantitative analysis of tetramine in biological samples including blood and urine. On the other hand, a previous study reported successful use of ion chromatography and LC-MS/MS for the quantitative analysis of tetramine in Neptunea collected from South Korea’s coastal regions [6]. Based on these findings, we hypothesized that an LC-MS/MS method would be efficient in quantitative analysis of tetramine in human’ biological samples. In this study, we developed an LC-MS/MS method and a protein precipitation method for quantitative analysis of tetramine in blood and urine, and used them to analyze two patients’ biological samples.
