Quick measurement method of 14C based on accelerator mass spectrometry

Abstract

The invention provides a measurement method of 14C, comprising: converting 14C in a 14C-containing sample into a carbonate; acquiring carbonate deposit; mixing well the carbonate deposit with metal powder to obtain a target; using an ion source to sputter the target and generate an anion beam, and guiding out the anion beam; subjecting the anion beam to mass selection to screen out ions having themass number of 14; converting the screened ions having the mass number of 14 into monatomic ions, and converting the anions into cations; screening 14C cations from the cations; detecting the 14C cations.

Description

technical field [0001] This disclosure relates to a 14 The measurement method of C, especially relates to a kind of method based on accelerator mass spectrometry 14 A quick way to measure C. Background technique [0002] The breath test refers to the non-invasive judgment of the physiological and pathological state of the body through the direct measurement of the components of the breath or the measurement of the symbolic gases in the breath after ingestion of specific compounds. Because of its simplicity, non-invasiveness, high sensitivity, and strong specificity, it has attracted the attention of researchers. Its clinical applications mainly focus on the digestive system, including the diagnosis of gastric Helicobacter pylori infection, gastric emptying measurement, and liver function evaluation. 14 C is currently the most widely used and ideal long-lived radioactive tracer nuclide for biological metabolism tests in the world. Its accurate determination is to carry out ...

AI Technical Summary

Problems solved by technology

Currently, CO 2 Breath test analysis methods have disadvantages such as low sensitivity, poor statistics, and high radiation dose

[0003] exhale 13 CO 2 It is mainly determined by gas isotope mass spectrometer or infrared spectrometer 13 CO 2 / 12 CO 2 The abundance ratio is used to achieve quantification. Due to the low sensitivity of the instrument and strong background interference, it is required 13 The abundance ratio of the C mark is greater than 99%, and the price is more expensive; while exhalation 14 CO 2 Measurement of gas samples by liquid scintillation 14 CO 2 The radioactive intensity, due to 14 The C nuclide has a long half-life (5730 years) and fewer decay counts, so it is labeled orally 14 The urea pills of C have high radioactive activity (0.75--1μCi), which has radiation hazards and cannot be used for the examination of pregnant women and children in sensitive groups.

For gastric emptying assays 99m Tc gastric scintigraphy is the current gold standard, but factors such as large radiation dose (3--5mCi), expensive equipment and high cost limit its widespread clinical promotion.

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