In general
LOC systems can be divided into three main categories based on materials and the fabrication technologies used for those materials: polymer systems, glass systems, and silicon systems. Silicon based LOC systems utilize fabrication techniques that grew out of integrated circuit (IC) fabrication technologies. Notable properties of silicon include its electrical conductivity and the wealth of techniques that have been developed for fabrication, surface treatment, and bonding.
Polymer based
LOC systems are a more recent development and there exist many fabrication methods, depending on the polymer used. PDMS (polydimethylsiloxane) is sold as a twocomponent liquid that hardens into a rubbery solid when mixed together. PDMS can be used with a surface patterned master to create half of an LOC device which is then completed by sealing the PDMS to a cover (e.g. to a glass slide). The surface patterned master can be micromanufactured from silicon or via soft lithography using a light sensitive mould material (e.g. SU-8). Many other manufacturing methods exist for polymers including embossing, lamination, injection moulding, laser machining, as well as all of the tradition direct machining methods (e.g. drilling or milling).
Glass-based
LOC system have the advantage that more is known about biochemical interactions with glass than with any other material. Many surface treatments exist for glass, and it has excellent thermal and optical properties. However, glass is more difficult to machine and designs based on glass need to adapt to the limited machining methods available.
from Herold and Rasooly (Eds)
in Lab-on-a-Chip Technology (Vol. 2)Further reading:
Labels: lab on a chip, Lab-on-a-Chip Technology, LOC