Mike Fisher PhD
Micro and nanotechnology is starting to show promise in the pharmaceutical industry. The two key questions in this field are ‘what is nanotech’ and ‘aren’t all drugs nanotech – after all, they are in the nano size range’. These can be answered fairly simply; Nanotechnology is where the nano-size of a substance affects its activity – the size placing the substance at the interface between quantum and material effects. The classic example to demonstrate these effects is that of gold nanoparticles. Bulk gold is insoluble and metallic-yellow in colour. However, once the gold is formulated as a nanoparticle it is soluble and the size of the particle determines its colour – from bright blue to vivid red.
Two key areas where nanotechnology is showing promise in the pharmaceuticals industry are tools for drug discovery, and secondly in formulation and delivery systems.
In the development of tools to support drug discovery, nanotechnology is developing a trend to move away from high throughput to high content screening, where greater information on fewer compounds is achieved. As our knowledge about drug-target interactions increases, it is becoming apparent that high-volume/low-content screening can miss extremely interesting interactions and effects. For example, SPR biosensors can detect a ligand binding step and measure the binding constants. But it cannot measure surface stresses caused by binding, which are an important factor for example in antibiotic efficacy against MRSA and VRE. Here nanomechanical cantilevers have been shown to be effective in providing extremely elegant information that can explain the difference between various drugs that appear to have the same binding kinetics.[i]
The move to high content screening has been slow due to the large investments in high throughput screening laboratories and so new systems need to be compatible. However, where systems...