Methods and devices for sample analysis

An automated or semi-automated method for sealing an array of wells having an aqueous fluid disposed therein by disposing a layer of immiscible fluid over the array of wells, using a processor to run a program to instruct a device to perform the steps comprising:

• actuating movement of a droplet of aqueous fluid towards a droplet of immiscible fluid by using digital microfluidics (DMF) electrodes such that the two droplets contact each other thereby forming a biphasic droplet comprising an aqueous phase formed by the droplet of aqueous fluid and a non-aqueous phase formed by the droplet of immiscible fluid;
• actuating movement of the aqueous phase of the biphasic droplet by using DMF electrodes thereby pulling the non-aqueous phase present in the biphasic droplet towards an array of wells;
• contacting the array of wells with the aqueous phase of the biphasic droplet by actuating movement of the aqueous phase of the biphasic droplet over the array of wells by using DMF electrodes;
• and
• contacting the array of wells with the non-aqueous phase of the biphasic droplet by actuating movement of the aqueous phase of the biphasic droplet to a position adjacent the array of wells by using DMF electrodes such that the non-aqueous phase is pulled over the array of wells,
• wherein contacting the array of wells with the non-aqueous phase of the biphasic droplet covers the array of wells with the immiscible fluid thereby sealing the array of wells.