Rapid detection depends on domestic instruments

In recent years, food safety issues and environmental pollution incidents have occurred frequently, and the market demand for rapid detection instruments has been increasing. Especially in the protection of large-scale natural disasters, rapid detection instruments are often used as the first screening method and play an increasingly important role in ensuring the safety of local food and drinking water.

Gao Zhixian, a researcher of the Chinese Academy of Military Medical Sciences, has been focusing on rapid detection technologies and instruments for more than 20 years. He has participated in emergency events such as Wenchuan, Yanliang and Lushan earthquake relief, Zhouqu mudslide rescue, and 7.5 events and pinning events. , as well as on-site food safety protection work in major events such as the Olympic Games and Shenzhou No. 3 to No. 10. Recently, Instrument Information Network (hereinafter referred to as "Instrument") specially interviewed him and asked him to quickly detect the role of the instrument in emergencies emergency handling / large-scale event support, rapid detection technology / new progress of the instrument, and the development of domestic rapid detection instruments. Problems such as space were answered.

Gao Zhixian, a researcher at the Chinese Academy of Military Medical Sciences Gao Zhixian, is the earliest team engaged in rapid detection research. Instrument: Why did you choose to engage in rapid test research?

Gao Zhixian: In the 1980s, the military put forward the need for rapid detection of equipment and equipment. So my research group began researching and developing rapid detection technology/instrumentation since 1987, which is arguably the first team in China to start this research.

At that time, everyone did not know enough about rapid detection. They all felt that it was meaningless to do a quick test and there was no technical content. In fact, this is a misunderstanding. It is very difficult to really achieve rapid detection and many new technologies are needed.

Instrument: How long did it take for you to develop the first rapid test instrument?

Gao Zhixian: Research units in the military are not the same as local ones. Their development is single and their progress is slow. Until 1992, we launched the first-generation "Physical and Chemical Inspection Boxes for Food Hygiene" and "Food Adulteration Testing Boxes" that are suitable for on-site rapid testing. In 1997, we launched the "Liquor Hygiene Detection Box" and were promoted in the military and localities. During the application, especially during the World Women’s Conference in 1995, the Beijing Epidemic Prevention Station (now Beijing CDC) and its district epidemic prevention station (now the Beijing District CDC) are equipped with this detection box. In 2004, the “Food Safety Rapid Detection Box” was developed. In addition to its application in the military anti-epidemic agencies, it was also extended to boarding schools and other units under the jurisdiction of the Beijing Municipal Education Commission. The quality monitoring system also used this detection box.

Later, under the funding of the “Tenth Five-year Plan” and “Eleventh Five-Year Plan” projects of the Ministry of Science and Technology and the National Natural Science Foundation of China, we have introduced a new generation of food safety rapid detection boxes through continuous improvement and innovation. The food safety inspection department has promoted more than 1,000 sets.

Drinking water and food safety rapid detection box A new generation of food safety rapid detection box Instrument: What are the technical advantages of this food safety rapid detection box?

Gao Zhixian: This food safety and quick detection box integrates reagents, equipment, intelligent micro-photoelectricity detectors and multi-functional optical back sensors. It is only a suitcase size and can quickly finish meat moisture and vegetables in 15s-30min. There are more than 30 key indicators for food safety testing such as residual pesticides, alcohol in wine, and nitrite in meat products, and the detection sensitivity is in line with national standards.

Because of its small size, easy portability, sensitive detection, accuracy, speed, and ease of operation, this food safety and quick detection box was used for food safety protection activities for major events such as the “two sessions” and “Shenzhou No. 10” spacecraft launches across the country. In the "big show their skills".

Rapid detection of instruments in emergencies is only qualitative and does not require quantitative Instruments: From the "Shenzhou" series of spacecraft, the Beijing Olympics, to the Wenchuan Earthquake, the Lushan Earthquake, and several emergency tests, you are involved. What are you responsible for in these incidents?

Gao Zhixian: In major events, in order to prevent some terrorists from choosing to use water and food in their hands and feet, such as poisoning, this will endanger the lives of many people. We are mainly responsible for this part of the fight against terrorism and security. During the hosting of the 2008 Beijing Olympics, all Olympic venues and some hotels and hotels were equipped with our new food safety rapid detection box to safeguard food safety during the Olympic Games.

Natural disasters can cause water and food to be subject to varying degrees of pollution. For example, after an earthquake, it is usually accompanied by rainfall. Rainwater flushes some domestic waste into rivers and causes water pollution. Earthquakes can cause power outages. Food moldy. We usually go to the disaster area within one or two days after the natural disaster occurs. We are mainly responsible for the local area of ​​drinking water, food safety monitoring and risk assessment and monitoring.

Instrument: How do you respond to food and drinking water safety problems?

Gao Zhixian: Once a problem is found, we will immediately use the on-site rapid detection equipment to detect the contaminated water or food. If the water source water quality test result is chemical pollution, we will first use the purification vehicle to remove organic pollutants, and then we can remove it after disinfection. Contaminants; If the test results are biological contamination, this is easier to handle and only needs to be resolved. In short, we will respond immediately after discovering problems, minimize the safety risk factor and ensure the health of the people.

Instrument: What are the requirements of this special field environment for rapid detection equipment?

Gao Zhixian: The rapid detection equipment cannot impose strict requirements on the site environment and requires certain environmental adaptability, such as temperature applicable range, anti-electrical wave interference, and oxygen consumption.

Rapid detection instruments sometimes only need qualitative, or semi-quantitative, with some related portable instruments for quantification. Of course, the demand for rapid detection instruments varies from occasion to place. This is a requirement for rapid detection of emergency emergencies. For example, we need to detect the composition and probable dose of toxicants as soon as possible and quickly find a detoxification method. Save people, do not need to measure the exact content of poison, accurate methods are generally more time-consuming, which can not meet the needs of the scene of high efficiency in an emergency.

Rapid detection instrument development direction: more portable, into series, information, integration Instrument: What are the problems with the rapid detection technology? What new results do you have for these issues?

Gao Zhixian: Immunoassay is one of the important methods for the detection of food contaminants. However, there are problems in the preparation of monoclonal antibodies and the poor specificity of polyclonal antibodies. How to simply and conveniently obtain antibodies with high specificity for small molecule contaminants is the current immunization. One of the key issues in the further development of detection methods. Our research group has taken the lead in constructing a ribosome display antibody library and screening out antibodies that obtain small molecule hormones. We have also used monoclonal antibody preparation techniques to screen out a variety of common residual agrochemicals antibodies.

Sample pretreatment is one of the biggest bottlenecks restricting the development of rapid detection instruments. At present, research hot spots in the field of sample pretreatment materials are molecularly imprinted polymers (MIPs). This is a rigid, three-dimensional functional material that has specific adsorption capacity for target molecules and is reusable. At present, we have successfully established a molecularly imprinted polymer material preparation technology and developed a series of molecularly imprinted nanomaterials such as organophosphorus, carbamate and other small molecule chemical contaminants and 11 veterinary drug molecules.

Based on the above research results, we have also developed a series of risk monitoring platforms for typical harmful factors, such as fixing molecularly imprinted materials on the surface of the piezoelectric sensor electrodes and establishing a molecularly imprinted-piezoelectric sensor detection technology platform. Sensitive detection of common contaminants in foods; for example, the introduction of molecularly imprinted materials into chemiluminescence sensors, and the construction of MIPs-Surface Plasmon Resonance (SPR) immunosensors for detection of small-molecule chemical contaminants. Samples need not be labeled. The sensitivity and specificity of this type of sensing technology have been improved; the use of advanced enzyme thermal detection technology, the introduction of beta-lactamase and carboxylated atrazine small molecule conjugates, can be used to achieve competition with the test object By combining specific binding sites on specific antibodies, we have developed a signal detection method that is not affected by the optical properties of the sample matrix. A simple calorimetric biosensor for sample pretreatment is used to detect the target in the sample to be tested. It is important for the control of pesticide residues. Means We have also developed a variety of high-throughput suspension chip technology for chemical pollutant detection, at home and abroad. The first realization of the suspension chip on the water seven kinds of pesticides and veterinary drugs simultaneously detected.

At present, we have put some new technologies into practical use, but there are still some new technologies that are still in our laboratory research stage. In the future, we will gradually realize the commercialization of instruments so that we can more widely promote applications and meet more market demands.

Instrument: What do you think is the future direction of rapid inspection equipment?

Gao Zhixian: It is more portable, serialized, informatized, and integrated. I think this is the development direction of rapid detection instruments.

It is more portable and can even be packed into pockets and brought to the scene to carry out risk monitoring. In series, such as protection against emergencies and large-scale activities, daily supervision and monitoring, we can provide a series of coping solutions; information is very important After the on-site inspection, the data will be directly transmitted to the laboratory for confirmation. This will have a more rapid and more accurate significance for the next step. The future rapid detection instruments will become more and more integrated, such as with molecular imprinting technology, nano-biotechnology, With the combination of new materials and technologies such as biosensing technology, there will be more room for rapid detection.

The rapid detection equipment is mainly developed domestically, and only rely on imported instruments will suffer losses. Instrument: How is the development status of China's rapid detection technology/instrument?

Gao Zhixian: More than ten years ago, the funds for rapid inspection projects were very few. Now that the funding for rapid inspection projects has been approved to increase, this shows that the Chinese government is currently paying attention to rapid detection technology research. From Beijing Zhongwei in the 1990s to Wanger after 2000, to now Weideweikang, Qinbang Biology, and Sino-German Biology, China’s professional team for rapid detection and R&D has become increasingly large, and rapid detection technology has developed at a very high rate. Fast, the technology level of the domestically-made rapid testing instruments and kits has been greatly improved, and the types are increasingly numerous. I think that the current domestic rapid inspection equipment is not inferior to the imported rapid inspection equipment and can fully meet domestic demand.

Instrument: Do you think there is much room for development of domestic rapid detection equipment?

Gao Zhixian: Foreign instrument companies lack understanding of China’s national conditions, and it is impossible to develop rapid detection instruments specifically for China’s national conditions. At the same time, the kits are expensive, and sometimes the supplements are not timely. In the event of an emergency, we will be in a very passive situation. Therefore, I believe that rapid testing must rely on domestic instruments. China should focus on the development of domestic rapid detection equipment, allowing imports of rapid detection equipment for comparison reference, but not only rely on imported equipment, otherwise we will certainly suffer losses in the future.