Overview

1.Background

In recent years, as marine resources continue to be exploited at high intensity, microbial epidemics and outbreaks of disease are endangering and constraining the development of related industries worldwide [1]. As NATer is located in the vast blue breadbasket of the South China Sea, we should be mindful of the dangers. The misuse of antibiotics is already a major threat to public health and safety, increasing the frequency of microbial resistance in nature and leading to some public health incidents due to the growth of it [2], including in the marine aquaculture industry, which is now suffering from its impact.

These resistant microorganisms can enter the human body through direct or indirect contact (e.g. the food chain) and can lead to various health problems. According to the European Centre for Disease Prevention and Control (ECDC) and the European Medicines Agency (EMA), approximately 25,000 Europeans (5.1/100,000 inhabitants) die each year from drug-resistant bacterial infections. The US Centers for Disease Control and Prevention (CDC) reported in 2013 that at least two million people in the US are infected with various drug-resistant bacteria each year, with more than 23,000 deaths directly caused by drug-resistant bacterial infections. In order to actively address the challenges posed by bacterial drug resistance and to maintain the health of the people, in 2016 the National Health and Family Planning Commission of China and 14 other departments jointly developed the National Action Plan to Curb Bacterial Drug Resistance (2016- 2020). Therefore, the development of detection technologies and tools for drug-resistant microorganisms has become an important part of maintaining marine resources and human health.

In summary, NATer conceived and subsequently designed a single-base, amplification-free, portable nucleic acid detection platform in combination with CRISPR/Cas detection technology for the application of marine drug-resistant microorganisms.

2.project:

The aim of this project is to study drug-resistant microorganisms in the ocean. NATer have designed a portable marine drug-resistant microorganism detector for this field. At present, although there are detection tools such as microplate readers, such devices are relatively expensive and bulky, and most human-computer interfaces use computer screens to connect to them and perform related operations, extremely inconvenient. Therefore, considering the cost, portability and simple operation process, we specially developed a hardware system to meet our needs. The system is relatively small in size, can achieve rapid detection, human-computer interface friendly and easy to operate.

Target Users

According to our preliminary research (jump to Integrated human practice), our hardware will be available primarily to practitioners in the marine (aquaculture) industry and the supporting industry chain (e.g. inspection and quarantine, environmental monitoring, etc.).

In the early stages of NATer's development, the main target users will be small and medium sized aquaculture companies who have a need for microbiological testing, but can only purchase small quantities of qRT-PCR equipment due to its high cost. Based on the programmability, accuracy and efficiency of CRISPR/Cas technology, NATer's nucleic acid testing equipment is expected to provide a revolutionary advancement in instrumentation for small and medium sized aquaculture companies when it becomes operational.

In the long term, NATer will provide customised testing equipment for the aquaculture industry chain, such as in the direction of inspection and quarantine, real-time environmental monitoring, or microbiological testing of personal home environments.

Operation procedure

In order to provide a good user experience, NATer has developed an Android-based human-machine interface. The device can be operated by touch.

（1）Set sample description, including sample name, culture room temperature, test time, etc.

（2）Click the start detection button

（3）Put the sample into the culture room when the temperature is reached

（4）Wait for the end of detection or click the end of detection button to end the process

To test the reliability of the microbiological testing device, NATer added the same samples ELISA in order to compare the results.

After comparison, the results of the NATer device were in general agreement with those of the ELISA, demonstrating the relative reliability of the NATer device.

User Experience Improvement

In the above process, NATer's Android-based interactive interface was well received by the stakeholders, who proposed to NATer to build a cloud-based sharing platform based on the nucleic acid information collected by the testing equipment, in order to improve the efficiency of each test and provide a more accurate and better service to customers.

Currently the entire structure of the portable marine drug resistance microbial detector is printed out by a 3D printer, so that the printed structure deviates slightly from the actual design of the 3D model and has a relatively poor aesthetic appearance. The temperature sensor protrudes above the thermally conductive aluminum resulting in a somewhat unreasonable internal structure, even if it does not affect the test.

In order to solve the problems above, we propose several solutions.

For the instrument's appearance: NATer will transfer the design to a specialist foundry for the construction of the device.

For temperature sensor issues:

1. design the temperature sensor interface under or to the side of the thermally conductive aluminum;

2. replace the inline temperature sensor with an infrared temperature sensor.

safety

In the early days of our product development, when we built a portable, single-base, non-amplified CRISPR/CAS13 & CAS14 nucleic acid detection platform, we first considered pre-social biosafety-related factors, faced with the potential risk of biological hazards, we have conducted full validation using model organisms such as E. coli. Ensure that our products are biosafety-free, and that our tool packaging and other options are in line with product safety testing, to fully safeguard its environmentally friendly characteristics.

Development Plan

NATer's single-base, amplification-free, portable nucleic acid detection devices based on Cas13a and Cas14a, coupled with TtCsm6, due to their lower cost, environmental requirements and simpler operating procedures, will be more widely used than existing qRT-PCR. After the technology has matured, NATer will develop conventional nucleic acid testing devices and customized devices, with the conventional devices serving as the main products for NATer's multi-dimensional development in data collection, R&D and marketing. In addition, customized nucleic acid testing devices will continue to be developed in the environmental, inspection and quarantine, and medical fields. Depending on the type of nucleic acid and relying on the characteristics of CRISPR/Cas programmable, products will eventually be developed to suit the needs of different customers.

The research of the products cannot be done without the support of the society, government and people. NATer plans to cooperate with the government and other organizations in the future to provide cost-effective nucleic acid testing equipment for less developed areas to cope with various possible public health events. At the same time, NATer started as a marine aquaculture (aquaculture) company and will subsequently develop into a multi-disciplinary microbiological testing company to continue to contribute to related industries, regions and societies.

Reference

[1] Dang Hongyue, Song Linsheng, Zhang Zhinan. Hazards of bacterial resistance in mariculture environments. Journal of Marine Science,2006,47: 29~40.

[2] Yufan Chen, Shiyin Liu, Zhibin Liang, Mingfa Lv, Jianuan Zhou, Lianhui Zhang.Quorum sensing and microbial drug resistance[J].Genetic ,2016,38(10):881-893.DOI:10.16288/j.yczz.16-141.