Research On Key Technologies In Pipetting High-throughput Nucleic Acid Extraction System

With the continuous development of medical technologies,more and more genetic diseases have been diagnosed.Nucleic acid,as an important genetic material,plays a significant role in storing and transmitting genetic information in the replication and synthesis of proteins.It has been found that nearly 2000 genetic diseases are associated with nucleic acid.The nucleic acid extraction is an important step in nucleic acid detection process.Rapid and efficient nucleic acid extraction is essential for the detection.In response to this demand,in this paper,we design a high-throughput nucleic acid extraction system based on the high-throughput liquid processing platform which is developed by our research group independently and conduct deep research on key technologies.Firstly,we optimize the design of mechanical gripper module which is assembled on high-throughput liquid handling platform.For the new gripper,the rotary encoder is selected and decelerator is fabricated with higher precision.Not only that,the trapezoidal screw with self-locking function is also used in the module.Through experiments,it has been proved that the precision and stability of the optimized gripper are improved a lot.In order to complete the experiment of nucleic acid extraction,we design a high-throughput magnetic separation module and an oscillation module.The mechanical design and function of each module are introduced in detail.Both modules acquire temperature by means of ADS1220 chip and then utilize incremental PID algorithm for temperature control.The accuracy of temperature control reaches ±0.5°C and the temperature control time is around 90 seconds.The magnetic beads transfer rate test and the protein concentration test are performed on the magnetic separation module and oscillation module respectively.The magnetic separation efficiency of the module is verified greater than 95% and the mixing effect of the oscillation module is good.Finally,we describe the framework and functions of the control software for the high-throughput nucleic acid extraction system.We perform the manual experiment,the experiment of portable nucleic acid extractor and the experiment of high-throughput nucleic acid extraction system separately.The results of the experiments indicate that the performance of the high-throughput nucleic acid extraction system which is developed by our research group is between the manual and portable nucleic acid extraction device.The whole system shortens the experiment time.However,the efficiency of the nucleic acid extraction needs to be improved.