Radioactive thin layer scannerIt is a high-precision analytical instrument that combines nuclear technology and chromatographic separation principles, mainly used to detect and analyze the distribution of radioactive substances in thin layer materials (such as filter paper, silica gel plate, polymer film, etc.). The core principle is to use the alpha, beta, and gamma rays released during the decay of radioactive isotopes, which are converted into electrical signals through detectors such as scintillation counters and semiconductor detectors. These signals are then processed and image reconstruction algorithms are used to generate two-dimensional or three-dimensional radioactive distribution images. This device can accurately determine the radiochemical purity of radiopharmaceuticals, ensuring effective separation of radioactive and non radioactive components in the drug. It also supports purity analysis of target products in reaction mixtures, such as drug intermediates labeled with isotopes such as ¹² ⁵ I and ¹⁷⁷ Lu.
Radioactive thin layer scannerPreparation before use:
1、 Equipment calibration and inspection
Power on preheating
Start the device 30 minutes in advance to ensure that the detector, electronic components, etc. reach a stable working state and reduce the impact of temperature fluctuations on the detection results. For example, some models of scanners require preheating to stabilize the internal temperature within ± 1 ℃.
Energy calibration
Use standard radioactive sources (such as ¹³ ⁷ Cs, ⁶⁰ Co) to calibrate the detector's energy and verify its ability to identify characteristic peaks of different nuclides. After calibration, the calibration curve needs to be saved for subsequent testing and comparison.
Functional Testing
Run the device self-test program to check whether the detector response, mechanical transmission (such as scanning arm movement), data acquisition system, etc. are normal. If any abnormalities are found (such as excessive noise or signal drift), the fault should be immediately investigated.
Software parameter settings
Set scanning parameters according to detection requirements, including scanning speed, step size, energy window range, etc. For example, when detecting low activity samples, it is necessary to extend the integration time to improve the signal-to-noise ratio.
2、 Environmental condition control
Temperature and humidity regulation
Ensure that the laboratory temperature is stable at 20 ± 5 ℃ and the humidity is controlled within the range of 30%~70% RH. Avoid placing equipment near heating, air conditioning vents, or humidifiers to prevent sudden changes in temperature and humidity from affecting performance.
Dust prevention and cleaning
Clean the dust on the surface of the equipment and inside the scanning chamber, use a dedicated vacuum cleaner or dust-free cloth to wipe, and avoid dust interference with optical components or sample contamination.
Shielding and Radiation Monitoring
Check if the lead shielding device is intact and ensure there are no cracks or damages. Use a portable radiation dose meter to monitor the background radiation in the environment and confirm that it is below the safety limit (such as ≤ 0.25 μ Sv/h).
3、 Safety protection preparation
Personal protective equipment
Operators are required to wear lead clothing, lead gloves, protective goggles, and personal dosimeters. If detecting high activity samples, respiratory protective equipment (such as dust masks) should also be equipped.
Emergency equipment inspection
Confirm that emergency flushing devices (such as eye wash stations and showers) can be used normally, and that the drugs in the first aid kit are within their expiration date. Post radiation warning signs and emergency process diagrams near the equipment.
Regional isolation
Define the testing operation area, set up warning lines or fences, and prohibit unrelated personnel from entering. If using open radioactive materials, it is necessary to operate in a fume hood and ensure that the exhaust system is functioning properly.
4、 Sample and reagent preparation
Sample processing
Pre treat the sample according to the testing purpose, such as dilution, filtration, or chemical separation. For example, when detecting radioactive markers in blood samples, plasma needs to be centrifuged first.
Standard product preparation
Prepare a standard solution that matches the sample matrix for drawing standard curves or validating detection methods. Standard products should be properly stored to avoid radiation degradation or contamination.
Thin layer board selection
Select appropriate thin-layer plates (such as silicone adhesive plates, aluminum oxide plates) based on the properties of the sample, and check their uniformity, thickness, and activation state. For example, polar adsorbents need to be used when detecting polar compounds.
Sampling and unfolding
Use a microplate to evenly spot the sample and standard on the starting line of the thin-layer plate, and the sample size should be controlled within the detection range of the equipment (such as 0.1-10 μ L). The developing agent needs to be freshly prepared to avoid volatilization or oxidation.