Abstract

Precise Contactless Spotting for Lab-on-Chip Applications

Wilhelm Meyer, Managing Director, microdrop Technologies GmbH

Lab-on-chip devices are used for a wide variety of health care applications, especially in the area of point-of-care diagnostics. These small microfluidic devices equipped with microchannels, chambers and other features carry out diagnostic tests by enabling reactions between patient samples and reagents. The devices deliver test results with very small sample volumes and in a short period of time. For production of lab-on-chip devices a precise and fast material deposition method is needed. Typically, the devices are produced at high numbers under high throughput conditions. The substrates may be made of different materials e.g. polystyrene or silicone, but in common is that these substrates typically have a structured surface which may consist of channels, mixing chambers or even wells which are used for precise detection. Also, different coating materials are used as pretreatment for better adhesion of reagents or confinement of fluids. Deposition or Spotting of reagents onto the chip is a demanding task and requires the filling of small cavities and microchannels with a high accuracy. This can efficiently be done with a microspotting platform based on in inkjet technology. The flexibility of this technology allows for custom-made solutions adapted to the specific customer needs. Especially how high accuracy concerning volume of spotted reagents and also precision of placement is achieved under high throughput production conditions is demonstrated by examples. Beside aqueous reagents (e.g. DNA- or protein solutions), Hydrogels and Cell suspensions are coming come more into focus as a material for the construction of organoids and similarly complex structures. The printing of Matrigels is explained with an example here.