1. Overview
For many years, the situation of excessive pesticide residues in vegetables has been prominent, and incidents of pesticide poisoning are often reported. The reason for this is that farmers do not apply pesticides according to the prescribed dosage, frequency, method, or safe interval, or use highly toxic or highly toxic pesticides that are not allowed to be used on vegetables; Secondly, the current standard for pesticide residue determination requires organic solvent extraction, purification, and the use of large analytical instruments, which makes it difficult to detect inexpensive vegetables anytime, anywhere, or quickly, resulting in inadequate supervision. Strengthening the publicity and guidance for farmers and establishing standardized rapid detection methods for pesticide residues that are suitable for China's national conditions are the key to solving the problem.
The pesticides currently used can be roughly divided into the following categories based on their chemical structure: organochlorine, organophosphorus, carbamate, pyrethroid, etc. In China, 70% of pesticides are organic phosphorus pesticides, while in the production and use of organic phosphorus pesticides in China, 70% are highly toxic and toxic, and many of them are prohibited from being used on vegetable crops. Although these pesticides degrade faster compared to organochlorine pesticides used in the past, their residues in fruits and vegetables are still more severe, and they can cause great harm to people's health. Timely detection of pesticide residues in fruits and vegetables is crucial for their safe consumption.
The QD-16N pesticide residue rapid detector is a new food safety detection equipment developed by our company based on the enzyme inhibition rate method in the national standard (GB/T 5009.199-2003) and agricultural standard method (NY/T 448-2001), combined with rapid detection method. It can accurately and quickly detect the residues of organophosphorus and carbamate pesticides in vegetables and fruits.
2. Application Fields
The QD-16N pesticide residue rapid testing instrument can be widely used for pesticide residue detection in areas such as unit canteens, hotels, vegetable production bases, food safety testing mobile vehicles, health and epidemic prevention, environmental protection, etc., including vegetables, fruits, Chinese herbs, pollution-free vegetables, and soil.
3. Instrument principle
The QD-16N pesticide residue analyzer is based on the principle of enzymatic reaction kinetics. If the tested sample contains organophosphate or carbamate pesticides, it will inhibit the activity of cholinesterase, affecting the reaction rate of the colorimetric system. The pesticide residue in the tested sample (inhibition rate) can be measured by measuring the rate of change of absorbance of the colorimetric system over time.
Calculation formula: S%=[(△ A0- △ At)/△ A0] × 100
In the formula: S% ： Inhibition rate;
△ A0: The change in absorbance of the control solution after 3 minutes of reaction;
△ At: The change in absorbance of the sample solution after 3 minutes of reaction;
Result determination: When the inhibition rate is ≥ 50%, it indicates the presence of high-dose organophosphorus or carbamate pesticides in the vegetables, and the sample is a positive result.
4. Product performance
◆ High detection efficiency
16 channel design, simple operation, fast speed, can simultaneously detect 3 samples, comprehensively improving detection efficiency.
Real time multi-channel continuous detection
Humanized and flexible design, 16 channels work independently, and channels can be freely selected to ensure measurement accuracy.
◆ High accuracy
Adopting imported special LED light source, it has good wavelength accuracy and repeatability, comprehensively improving detection efficiency.
◆ The instrument has a long service life
Adopting semi permanent LED light source, automatic switch energy-saving design, and non continuous working mode. The service life can reach 10 years.
5. Instrument technical parameters