Surfaces are all around us and everywhere, and many ongoing research and development projects involve surfaces in one way or another.

Ranging from large scale to small, and everything in between, surface characteristics, surface exposure and surface behavior must be taken into consideration for expected and optimal performance in the planned context at end use.

What we cannot see

Sometimes, the behavior at the macroscale is significantly influenced by the behavior at the nanoscale. Think, for example, about nanostructures on implant surfaces that will make the new part attach to bone, anti-fog coatings on lenses to prevent water droplet formation, asphaltene adsorption and fouling of oil pipelines, silver nanoparticles in sportswear to kill bacteria and prevent smell, protein drugs that will cure disease. In such cases, the characterization and evaluation of the surface interaction phenomena will be a major part of the research and/or development work, so that the properties can be tailored and controlled for the desired outcome at the macro-scale.

From question to answer – Surface Interactions analysis at the nanoscale

QSense QCM-D instruments can monitor surface interaction phenomena in real time at the nanoscale. They help in the exploration of unknown surface interaction behavior, the verification of well-known interaction processes and in tailoring behavior for a desired outcome by answering questions such as - Are my molecules interacting with this specific surface? Yes/No/How much/How fast/What process? How do the molecules behave? How are they arranging themselves? Are they staying at the surface or are they leaving after some time? Sometimes answering questions at the nanoscale will help you solve problems at the macroscale.

Explore. What happens at the surface? Investigate unknown molecule-surface interactions, or new contexts for the surface molecule combination. Is this molecule interacting with the surface, yes/no? How does the interaction process vary as a function of surface material, pH, temperature, sample concentration or other parameters? Investigate your system in various parameter domains to map out the behavior and to gain an understanding of unknown systems. Systematically vary the unknowns in a controlled manner.

Characterize and evaluate systems that you are already familiar with, and where the system behavior needs to be verified or controlled. I know my molecule is adsorbing/binding, but what is the coverage, how does it arrange itself at the surface, is the arrangement at the surface dependent on the coverage, or dependent on any other key factors? Characterize the system behavior, verify your process, the system reproducibility or run multiple repeats of selected parameter sets for statistics.

Optimize and tailor systems for a desired behavior and certain requirements at a planned end use. I know my molecule adsorbs/binds to this surface, but at what conditions do I get the maximum coverage, the maximum thickness, the fastest uptake, no uptake, the desired release rate or something similar? Run the same experiment over and over with minor variations in the experimental parameters. Compare and rank the results in the search for a certain outcome.