Monochromatic excitation X-ray fluorescence (ME-XRF) spectrometry is a novel technique for trace element analysis, characterized by its simplicity, rapidity, and low cost. The objective of this study was to evaluate the applicability of ME-XRF technique for the measurement of thallium in biological samples. Acute and subacute thallium poisoning experiments were conducted to simulate various scenarios, with blood, urine, and 10 distinct organs collected. Detection was initially performed using ME-XRF technique, followed by validation with inductively coupled plasma mass spectrometry (ICP-MS). Excellent agreement between ME-XRF and ICP-MS values was demonstrated by means of paired sample t-tests and intraclass correlation coefficients. Subsequently, the practical implementation of the proposed technique was demonstrated through an actual case study. In conclusion, this study validates ME-XRF as a suitable alternative to ICP-MS for the measurement of trace heavy metals in biological samples. These efforts promote the development of simpler and faster techniques for heavy metal detection, thereby presenting novel avenues for the prevention and diagnosis of heavy metal poisoning.
An economical, rapid, and sensitive method of gas chromatography-mass spectrometry (GC-MS) was developed and validated to determine the presence of six pesticides (dichlorvos, acetochlor, atrazine, chlorpyrifos, α-endosulfan, and β-endosulfan) in human plasma. The pesticides were extracted with acetonitrile and concentrated using anhydrous sodium sulfate. Then, the target compounds were analyzed and quantified with GC-MS using borneol as an internal standard. Separation was performed on a HP-5MS capillary column (30 m × 0.25 mm × 0.25 µm) with temperature programming. Detection was accomplished under electro-spray ionization (ESI) in selected ion monitoring (SIM) mode. Under optimized conditions, satisfactory linear ranges of 0.05-10 μg/mL were obtained for all of the analyzed pesticides. The linear correlation coefficients were greater than 0.99. The average recovery was between 86.8 and 106.5%. The inter- and intra-day precision ranged from 1.7-14.5% and 4.2-13.8%, respectively. Dichlorvos was unstable in plasma both at room temperature and when frozen. The other five pesticides were stable after storage at – 20°C for 17 days and two freeze-thaw cycles. Thirty-five plasma samples from 15 patients with acute self-poisoning were analyzed using this method. Dichlorvos was found in 13 plasma samples with a mean concentration of 0.289 μg/mL, and atrazine was found in 6 with a mean concentration of 0.261 μg/mL. Acetochlor was found in one plasma sample (0.153 μg/mL). This method is simple, reliable and cost-effective. It takes little time and does not waste solvents, and it can be used to routinely detect six pesticides in patients with acute poisoning.
危险品化学品经营许可证（带存储）