A Design For Multichannel Power Supply Of Microfluidic Chip Electrophoresis

Microfluidic chip technology,as an effective Miniaturized Total Analysis technology,has been widely used in fields such as medicine,chemistry,and biological analysis.In the analysis of microfluidic chip electrophoresis,the method of electric field driving is often employed to achieve the automation of the microfluidic device,through controlling the work of electrophoresis by the output direct-current voltage of the power supply of microfluidic chip electrophoresis.Because the original power supply of microfluidic chip electrophoresis has the problems of few output voltage channels,unstable output and incomplete function in current detection,an multichannel power supply of the microfluidic chip electrophoresis was studied and designed.With C8051F060 as the control core,an multichannel power supply of the microfluidic chip electrophoresis was designed based on 7 high-voltage modules.The microprocessor was used to control the output voltage of the DAC(Digital-to-Analogue Conversion)circuit,and to regulate the output voltage of the 7 high-voltage modules.Besides,the relay array was used to switch the 7-channel voltage to 16-channel voltage and to control its voltage output.The 16-channel output voltages was in one-to-one correspondence with the set voltage values of the input devices.Moreover,the 16 set voltage values were designed to automatically identify and match the 7 high-voltage modules by the classification algorithm of design voltage.In addition,a current detection circuit was designed to detect the output voltage of the electrophoresis power supply and the current in the microfluidic chip channels.The detected output voltage,combined with the median filter algorithm and the voltage stabilization algorithm,was utilized to improve the accuracy and stability of the output voltage.The detected current in the microfluidic chip channel was used to regulate the voltage of each channel,and further,to control the state of the solution in the channel.In this case,the electrophoresis power supply achieved a voltage output with 16 channels,which was continuously adjustable from 0 to 2000V DC,with the maximum output current of 2mA.Furthermore,users are allowed to set the voltage via the keyboard with some user-friendly functions such as setting parameters and performing injection and separation with one key.What’s more,a LCD was equipped to display the input data in real time and monitor the output voltage and current.In addition,the upper computer software was developed based on LAB VIEW,which could facilitate the parameter setting and data display.A test was conducted on the output characteristics of the electrophoresis power supply,its time drift and performance of current detection circuit.The data showed that the 16-channel output voltage of the system was stable,with high precision as well as stable and reliable current detection functions,which met the design requirements.The application of the electrophoresis power supply to microfluidic chip electrophoresis experiments achieved satisfactory results.The study results indicate that the power supply met the needs of microfluidic chip electrophoresis analysis,with significant value in market promotion and application.