Design Of A Rapid Detection System For Microalgae Cells In Ballast Water Of Ships

In order to prevent the ship from tilting and ensure the stable operation of the ship,the seawater loaded into the ship's ballast water contains a large number of plankton,which may lead to the invasion of foreign organisms and cause serious damage to the marine environment.According to the D-2 standard in the ballast water convention proposed by the international maritime organization(IMO)and relevant guidelines,the concentration of living organisms with a size greater than or equal to 10?m and less than 50?m should be less than 10/mL,and the organisms that meet the size range are mainly microalgae cells.Based on this,this paper proposes a portable high-throughput marine ballast water microalgae cell rapid detection system based on microfluidic chip.The system is based on microfluidic chip,combined with the principle of chlorophyll fluorescence detection of microalgae cells to achieve rapid detection of microalgae cells in ship ballast water.The system designed in this paper includes two parts:hardware and software.The hardware part includes:microfluidic chip module,fluorescence excitation and receiving module,signal processing module,ARM control module,and auxiliary modules,namely power module,valve pump pressure driving module and mechanical module;among them,microfluidic chip module as the sample detection platform,the appropriate chip structure can sense the sample characteristics to the greatest extent;fluorescence excitation and receiving module can excite it,it can send and receive chlorophyll fluorescence of microalgae cells,and convert the light signal into electrical signal;the signal processing module is mainly a filter and amplification circuit,which can amplify chlorophyll fluorescence signal of microalgae cells and improve the signal-to-noise ratio of the detection system;the ARM control module can drive the work of the external analog-to-digital conversion chip;the power module can provide appropriate voltage for each hardware;the valve pump pressure drive can control the switch and speed of sample flow and monitor the pressure generated in the detection process;the mechanical module has designed a suitable shell structure,which integrates all hardware parts in it.The software mainly includes:collection,calculation,export and display of chlorophyll fluorescence signal data of microalgae cells.In order to verify the performance of the system,Chlamydomonas reinhardtii cultured in the laboratory was used as the sample to carry out concentration gradient experiment,heat treatment experiment,chemical treatment experiment and chlorophyll extraction experiment,which verified the accuracy and stability of the system.The system designed in this paper has the advantages of high speed,high throughput and portability,which provides further support for maritime inspection and ship self-inspection.