Application Note

The I.DOT Liquid Handler DropDetection Technology Explained

DropDetection: a unique feature for volume verification, quality control, and dispensing protocol optimization.

Non-contact, low-volume dispensing depends on generating individual and discrete droplets. They typically range from pico- to microliters, and volumes this small can’t be evaluated visually. Immediate Drop-On-Demand Technology (I.DOT) is a non-contact, low-volume dispensing platform. The general principle is based on a hole (less than 100 μm) in the bottom of a microtiter plate well, where surface tension and capillary forces retain the sample liquid in the cavity. Applying a pulse of air pressure on top of the well forms a precise droplet that can be released into or onto almost any target.

Each I.DOT Non-contact Dispenser is equipped with DropDetection to interface with the low-volume world. DropDetection is a patented feature unique to the I.DOT. It enables detection and counting of every droplet released during a dispensing run. It acts as a simple yet powerful tool for quality control and protocol optimization. DropDetection is mounted under the I.DOT One source tray (Figure 1). It’s a circuit board that leverages 96 miniaturized light barriers to detect every droplet that each source plate position generates. DropDetection identifies changes in light intensity to detect droplets passing the light barrier. After dispensing is complete, DropDetection provides a text file and color-coded result. Green indicates successful dispensing and red indicates an error. If the software recognizes the error, it displays the potential reason as well.


Figure 1. DropDetection PCB Counts Droplets Dispensed by the I.DOT Non-contact Dispenser

This application note highlights how DropDetection reliably and robustly detected the expected outcome. This example was performed with water. However, the DropDetection works with every dispensable liquid — including DMSO, glycerol-containing solutions and more. Contact Dispendix for more information on dispensable liquids. DropDetection has great potential to control dispensing quality. It’s a noninvasive recording technology that accurately identifies dispensing faults to optimize dispensing protocols.

Click here to download the application note.

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