July 15th, 2005

P2i surface enhancements for pipette tips reduce retention and open up other functional capabilities

Porton Down, UK – P2i Limited has developed a coating technology that will radically increase the effectiveness and flexibility of pipetting. Using its proprietary cold plasma-enhanced chemical vapour deposition (PECVD) process, P2i can apply nano-thin coatings to pipette tips; this dramatically enhances their performance, virtually eliminating liquid retention. P2i-enhanced pipette tips produce more accurate and reliable results and can reduce reagent costs by up to 10%. The ultra-low adhesion, pin-hole free coating has a surface energy 3x lower than Teflon® (PTFE) and has no leachable components.

According to P2i’s CEO, Quentin Compton-Bishop, “Pipetting is an important, routine process in proteomics and drug discovery where thousands of tiny samples have to be analysed. When measuring small volumes the slightest sample loss can cause downstream problems. By using our new coating process almost all of the sample can be expelled, enabling more reliable results. Moreover, when sample drugs and reagents can cost thousands of dollars per gram, reducing retention and waste will help save laboratories money.”

P2i’s cold plasma process can be used to create a variety of other surface modifications which could increase the flexibility of pipetting. Mr Compton-Bishop commented, “Our process can be used to deposit a range of functional groups on both plastic and glass surfaces, besides the ultra low surface energy enhancement which produces the low retention effect. For example, we can create hydrophilic surfaces and other specific reaction sites for proteins.”

Moreover, there is also the potential to give the inner and outer surfaces of pipette tips different surface coatings, further expanding the possibilities. Once modified using the plasma process, pipette tips can be gamma irradiated as required to make them suitable for sterile techniques.

P2i’s patented plasma process was originally developed by the UK Defence Science and Technology Laboratory (Dstl) in collaboration with the University of Durham, to protect the armed forces against chemical attacks by enhancing uniforms and equipment with super-repellent coatings. The coating technology is now proving ideal for pipette tips, medical textiles, filters, microplates, and instrumentation. Using plasma or ‘ionised gas’, proprietary chemicals can be deposited in layers only molecules thick over any surface. The polymerised compounds bind at the molecular level creating an invisible layer that does not leach. The super liquid-repellent coating for example, has a 3x lower surface energy than the benchmark Teflon® (PTFE) and unlike other hydrophobic treatments, it is also able to repel 100% isopropylalcohol (IPA) and oils.

The specialised plasma chambers used for the plasma treatments are robust and can be scaled to fit the process. P2i’s onsite facilities include 40-litre, 300-litre and 2000-litre chambers, supported by the expertise of its team of plasma process chemists. Mr Compton-Bishop commented, “Our range of chambers can process single-use disposable products as small as frits and pipette tips in their thousands through to larger items such as whole medical devices and protective apparel. For high level users, however, we can install bespoke chambers at customer sites under licence.”