1、 Daily operation standards
Preparation and Inspection of Reagents
Ensure that the reagent bottles (such as acetonitrile, activators, oxidants) are well sealed, maintain stable argon pressure, and prevent external air from entering and affecting the synthesis effect.
Before synthesis, check the remaining amount of reagents and replace empty bottles in a timely manner to avoid synthesis interruption caused by insufficient reagents.
Sequence input and parameter settings
Input the target DNA sequence through computer-aided design software, considering codon preference, secondary structure, and restriction enzyme sites.
Confirm whether the synthesis steps (such as deprotection, coupling, blocking, oxidation) are correct, and select the end method (such as TritylonAuto retaining the 5 '- DMT group for subsequent purification).
Synthesis process monitoring
Before starting, run the StartColumn step to check if the position of the composite column is correct.
During synthesis, the release of DMT cations is monitored through a conductive flow cell to determine the progress of the reaction.
Regularly check whether temperature, pressure and other parameters are within the normal range.
product processing
After synthesis, the product is cut from the solid-phase carrier and purified by OPC, PAGE, or HPLC to remove short fragments and salt ions.
After purification, the product should be packaged and stored to avoid repeated freezing and thawing.
2、 Key points of daily maintenance
Bottle stopper "O" ring
Check once a month and replace at least once a year. If white precipitate appears, clean with acetonitrile cotton swabs.
When replacing, clamp the old ring with hemostatic forceps to ensure that the plug is particle free before installing the new ring and conducting a pressure test.
Liquid storage bottle and pipeline
Keep the liquid storage bottle clean and regularly check the argon pressure and pipeline airtightness.
Clean the pipeline with new reagents before synthesis to prevent residual old reagents from interfering with the reaction.
Flow path throttle valve
Clean once a month, boil in water for 15 minutes, and then use methanol ultrasonic cleaning to prevent blockage.
Instrument cleaning and dust prevention
Wipe the outer shell with a damp cloth every week to avoid air vents; After the high-sensitivity experiment, sterilize the reaction chamber by irradiating it with ultraviolet light for 15 minutes.
When not in use for a long time, turn on the device 1-2 times a week for about half an hour each time to prevent moisture from affecting the components.
3、 Common troubleshooting
Low synthesis yield
Reason: Reagent failure, pipeline leakage, synthesis column position deviation.
Solution: Replace the reagent, check the airtightness of the pipeline, and recalibrate the position of the synthesis column.
Insufficient purity of the product
Reason: Improper purification method and incorrect synthesis steps.
Solution: Optimize purification conditions (such as adding HPLC purification steps) and check if the synthesis parameters are correct.
Instrument alarm or interruption
Reason: The waste liquid bottle is too full, the power supply fluctuates, and the temperature is abnormal.
Solution: Empty the waste liquid bottle, use a regulated power supply, and check if the temperature sensor is faulty.
Abnormal data (such as fluctuations in conductivity values)
Reason: contamination of the conductivity cell and impurities mixed in the reagent.
Solution: Clean the conductivity cell, replace with new reagents, and recalibrate.
4、 Operation precautions
Aseptic environment: Primer synthesis is sensitive to contamination, and gloves should be worn during operation to avoid contamination by exogenous DNA or enzymes.
Reagent storage: Acetonitrile and other solvents should be stored away from light, and activators and oxidants should be sealed to prevent moisture.
Data recording: Detailed recording of the synthesized sequence, reagent batch number, and quality inspection chart for each batch, facilitating traceability of issues.