When dealing with nano-surfaces, understanding the surfaces of interest cannot be overlooked. Appropriate surface testing and analytical techniques must be adopted. Plasma treatments and depositions are usually in the 1-15nm range for chemical modifications and 15-250nm range for coatings. More widely accepted characterisation techniques such as SEM/EDX (Scanning Electron Microscopy/Energy Dispersive X-Ray) techniques image on the 10’s of nanometres to micron scale and take 99% of their elemental information from 1μm+ below the surface. In order to chemically characterise the surface properly ‘true’ surface analytical techniques such as XPS (X-Ray Photoelectron Spectroscopy) and SIMS (Secondary Ion Mass Spectrometry) have to be utilised.
Portal Medical utilize a variety of analytical techniques and are experts in XPS testing and interpretation. All of the intellectual property within the company has been primarily gained from the testing and analysis of the nano-coatings developed for pharmaceutical devices.
XPS is surface sensitive technique which chemically characterises the outermost 5-8nm of a surface providing quantified elemental and chemical functionality information. A beam of X-rays of known energy irradiate the surface. This energy is enough to cause electrons from the outermost atomic layers to be emitted. The energy of these electrons is measured in an electron analyser. The energy of the X-rays arriving at the surface and the energy of the emitted electrons is now known, so the difference gives the binding energy of the atom from which it came, hence the element can be determined. By looking at small regions of the spectrum at high resolution, subtle shifts in the binding energy can determine the functionality of the element, i.e. what it is bound to.
Portal Medical can provide sub-contract testing services, offering XPS, SIMS, SEM/EDX and contact angle testing (for surface energy calculations).
Our in-depth knowledge of testing techniques and experience of various and varied materials enable us to both test product and interpret the data. We don’t just report the data, we explain what the data means for you.
All testing is accompanied by a full analytical report.
Please contact us to discuss your testing requirements.