The Crystallography Core has acquired the TTP Labtech’s Dragonfly, a new, fast liquid handling system with disposable positive-displacement pipette tips that can handle any liquid-type independent of viscosity with no cross-contamination. The liquid handler is ideal for designing and dispensing gradients from a few stock solutions into 24/48/96/384-well plates. It can be used for dispensing custom crystallization screens, preparing fluorescence assay plates or any other gradient plates.

The liquid handler is quite easy to use: the design, preparation and dispense of a 5-solution mix in a 96-well plate with 60 µl per well for a completely untrained person takes less than 15 minutes from scratch.

_{The Dragonfly has a small desktop footprint and is controlled by a laptop computer. The low dead-volume reservoirs from which the solutions are aspirated are inexpensive ($0.75), disposable, but can be reused if desired.}

_{The pipette can aspirate 4 ml of solution and dispense in bursts of 0.5 - 6 µl. So, the minimum dispense volume is 0.5 µl and dispensing 60 µl in a well will take 10 quick bursts. The tips are inexpensive ($1.25), disposable, but can be reused if desired.}

_{An accessory to the Dragonfly is the MX One mixer which can mix viscous solutions such as glycerol and PEGs (polyethylene glycols) to homogeneity in 96-well plates within seconds. The mixer uses a block of pins that act similar to an array of coffee stirrers oscillating at high-speed to mix the dispensed solutions. The 96-pin array ($10) is easy to clean and reuse.}

_{Within seconds, a mix of 80% glycerol with water or ethanol can be stirred to homogeneity, which is almost impossible to achieve on a shaker even after many hours.}

For details on using the Dragonfly or the Mixer, please contact Lokesh Gakhar in the Crystallography Core Facility.