Applications of AFM in pharmaceutical sciences

Atomic force microscopy (AFM) continues to find ever wider applications in the fields of materials characterisation and life sciences. By using a small tip to scan across the sample's surface, the requirement to focus light and electrons as with light and electron microscopies is eliminated; this overcomes the Rayleigh criterion resolution limit, enabling nanometre and sometimes atomic resolution imaging, depending on the sample and / or imaging regime, to become routine. AFM can be operated without the need for conducting or stained samples and therefore can be operated in physiological media. Further, the probe can be used to push into or pull away from sample surfaces, yielding quantitative nanomechanical and adhesion data, which can also be displayed graphically. This chapter will discuss the fundamentals of AFM and highlight a few recent applications with relevance to pharmaceutical science.