Application method for automatic micro droplet array screening system with picoliter scale precision

An application method for an automatic micro droplet array screening system with picoliter scale precision, wherein the system comprises a capillary, a fluid driving system in connection with the capillary, a microwell array chip, a sample/reagent storage tube and an automated translation stage, the application method comprising the following steps:

• (1) filling the fluid driving system and the capillary with a carrier fluid, and removing air bubbles inside the capillary, wherein thermal expansion coefficient of the carrier fluid ranges from 0.00001/° C to 0.0005/° C;
• (2) immersing a sampling end of the capillary into a first oil phase that is mutually immiscible with and above an aqueous sample in the sample/reagent storage tube, and aspirating a plug of the first oil phase into the capillary for separating the aqueous sample and the carrier fluid, wherein the carrier fluid and the first oil phase are mutually immiscible;
• (3) immersing the sampling end of the capillary into the sample/reagent storage tube and aspirating a predetermined volume of the aqueous sample into the capillary;
• and
• (4) moving the sampling end of the capillary to a location above a second oil phase in and above microwells on the microwell array chip, and pushing the aqueous sample in the capillary into the microwells to form droplets of the aqueous sample, wherein the carrier fluid and the second oil phase are mutually immiscible.