The hottest hand, HSCE holds electrophoresis in th

  • Detail

"Handheld HSCE, hold electrophoresis in the palm of your hand" - the team of Zhejiang University has reached a new high in the development of micro analytical instruments

recently, the research group of Professor Fang Qun of Zhejiang University developed a high-speed capillary electrophoresis analyzer that can be completely handheld and work independently, which is by far the smallest high-speed capillary electrophoresis analyzer based on laser-induced fluorescence detection in the world, This achievement was published in the academic journal "scientific

reports" under the title of "a

low cost palmtop high speed capable electrophoresis Bioanalyzer with laser

induced fluorescence detection", and received highlights from the station

appearance of handheld high-speed capillary electrophoresis biochemical analyzer

high speed capillary electrophoresis (HSCE) technology has been rapidly developed in the field of analytical chemistry since it was proposed in 1991 because of its fast, efficient and low sample consumption. In recent years, the development of point of care testing (POCT), environmental monitoring, on-site investigation and space detection has put forward higher requirements for the miniaturization and automation of analytical instruments. With the development of microfluidic technology and the integration of electronic components, miniaturization has also become an important development direction of HSCE system

although the sparrow is small and has five internal organs, the minimalist strategy shows magic power

the overall size of this handheld HSCE analyzer is only 90 mm × 75 mm × 77 mm (length × wide × High), weighing 300

g, the cost is only about 3500 yuan. Although the volume is small, it has integrated five parts: notched tube array spontaneous injection module, capillary electrophoresis module, orthogonal laser, and wood recyclable induced fluorescence detection module, high voltage module and electronic circuit control module. In the development process of the instrument, the strategy of "minimalism and miniaturization" is adopted, that is, based on the essential understanding of the instrument analysis principle and the results of the previous basic research, the instrument is designed to simplify the system to the greatest extent, retain the core functions, delete the temporarily unnecessary secondary functions, and fully borrow the low-cost commercial components in other disciplines to build the instrument system, so as to simplify the system structure, reduce the volume of the instrument At the same time, the analytical performance can still reach the level equivalent to that of the conventional analytical system

the notch tube array automatic injection technology, skin upgrade translational spontaneous injection technology, oblique 45 ° detection orthogonal laser-induced fluorescence detection technology with independent intellectual property rights previously developed by the research group provide a solid foundation for the development of miniature HSCE analyzer. The minimalist and miniaturization strategy, the adoption of low-cost components, and the maximum integration and optimization of the electronic circuit of the instrument jointly promote the introduction of this miniaturized instrument. Use the micro translation table used in the digital camera autofocus module purchased on Taobao, and 200

μ L centrifuge tube, you can build an automatic notch tube array automatic injection system, the volume is only 1% of the traditional translation table system, its moving distance can reach 17 mm, and the positioning accuracy can reach 10

μ m. The cost is only 20 yuan

in the development of the laser-induced fluorescence detection module, although the small 405

nm laser diode light source, photodiode detector and focusing lens are used in accordance with the minimalist and miniaturization strategy, the unique oblique 45 ° orthogonal optical path and the in-depth optimization and exploitation of the potential of the system can still retain high instrument detection performance. Under the condition of s/n=3, the detection limit of fluorescein sodium reaches 1.02 ×

m, which is comparable to some conventional laser-induced fluorescence detectors using photomultiplier tubes. In addition, the laser light source, laser focusing lens, capillary support and alignment device, fluorescence collection lens, fluorescence filter, photoelectric detector and other elements can be integrated by using the self-designed and processed integral optical path frame, so that the volume of the entire detection module is only 44

mm × 42 mm × 40 mm。

in the capillary electrophoresis separation part, the micro volume injection of 90

PL can be realized by using the notched tube injection system and the translational spontaneous injection method, that is, the high-speed capillary electrophoresis separation operation can be completed by using only ordinary short capillary tubes without using expensive and complex electrophoresis chips. At the same time, the miniaturized high voltage module (22 mm × 22

mm × 22 mm), which can provide electrophoresis voltage of 0 to - 6000 v

people familiar with the development of analytical instruments know that to realize the miniaturization of analytical instruments, the electronic control system of the instrument is one of the key difficulties. The electronic control system needs to realize the real-time acquisition and processing of fluorescence signals, the real-time display of spectra and the preservation of data. More importantly, to realize the real handheld application, the whole system needs to be powered by a small battery, and the laser diode, micro translation table and electrophoresis high-voltage module in the analyzer are all large power consumers for the battery. Therefore, in addition to using the ultra-low power embedded microcontroller to realize the integration of the control system, the system also made a lot of efforts in reducing power consumption, and finally successfully realized the battery power supply of the instrument. A single lithium battery with a capacity of 1150

MA can provide more than 10 hours of continuous working time

photos of the internal structure of the handheld high-speed capillary electrophoresis biochemical analyzer

the separation mode is diversified, and the application of the instrument is particularly promising

the handheld HSCE analyzer uses a capillary of 3.8

cm as the separation channel, and the time setting dialog box of the electro display system of three amino acids can be completed in only 7 seconds. In such a short time, there will be no obvious Joule heat effect, and the electrophoretic separation can obtain about 1 μ M

high separation efficiency of tray height. This handheld HSCE is not only suitable for the separation of amino acids by capillary zone electrophoresis, but also realizes the rapid separation of chiral amino acids (D, L-leucine and D, L-aspartic acid) by micellar electrokinetic capillary chromatography, and also realizes the separation of 5

DNA fragments and 3 proteins by capillary gel electrophoresis. The instrument is also applied to the analysis of PCR products and real samples of enzyme digestion products in KRAS proto oncogene diagnosis. The electrophoretic separation map is directly displayed on the liquid crystal display on the instrument shell and synchronously stored on the microSD data memory card. It can also be wirelessly sent to the or tablet computer through Bluetooth module for real-time monitoring

photos of the separation results of the handheld high-speed capillary electrophoresis analyzer

looking at the current demand and the performance characteristics of this handheld HSCE analyzer, davidhummel, CEO of Victrex, said that as a starting point, this instrument will help to open up more new application fields of HSCE: a few minutes of DNA fragment separation is expected to replace the cumbersome and time-consuming plate gel electrophoresis and be popularized in the majority of biochemical laboratories; Replace electrophoresis chips with low-cost capillaries that are cheap and easy to get. Automatic operation and convenient control of four buttons have become the stepping stones to enter the family, so as to realize individualized health management and disease prevention; Battery powered ultra long standby, this is a walking HSCE, which can be used for bedside detection, infectious disease monitoring and so on

the first author of this paper is Pan Jianzhang, associate researcher, Dr. Fang pan and Dr. Fang Xiaoxia of the Institute of microanalysis systems, Department of chemistry, Zhejiang University, and the corresponding author is Professor Fang Qun of the Institute of microanalysis systems, Department of chemistry, Zhejiang University. Special thanks to the National Natural Science Foundation of China (, and, etc.) for their support for this work! Accordingly,

scientific reports article link:

report link:

Copyright © 2011 JIN SHI