In modern medicine, scientific discoveries and technological progress have often been milestones for better disease understanding and more efficient treatment methods. The microscope, for instance, made it possible to detect bacteria as pathogens, which was fundamental for developing therapies to fight against them. Nanosciences and nanotechnology belong to the newest branches of science and are regarded by many researchers as key technologies of the 21st century. The question arises as to what role this technology could play for medicine.
Nanotechnology – the molecules’ tweezers
Nanotechnology is about extremely tiny objects such as atoms, molecules, aggregates and surfaces that can be examined and treated with the help of innovative devices and structured for specific uses. By manipulation of matter on a scale of one nanometre (being one millionth of a millimetre), the historically split sciences of physics, chemistry, biology and medicine become all intertwined, making nanoscale technologies a unique field of interdisciplinary research.
Why do we need nanotechnology in medicine?
The most basic entity of all living organisms, the cell, consists of a variety of tiny structures, the organelles. These are made of biomolecules interacting with one another, combining mechanical and biochemical functions on the nanometre scale. Therefore, these molecular ‘nanomachines’ are the foundation of all living organisms. ‘Nano’ is not primarily a technological invention of our times but actually is a fundamental feature of life in general.
Pathological processes take place within the nanorange, too. Many diseases begin to unfold in specific cell types with malfunction on the level of organelles and cellular biological ‘nanomachines’. By contrast, most of medical methods applied today are microscopic (e.g. scalpel, radiotherapy, cardiac catheterization) and therefore too crude for sick cells. As an alternative, systemic drug medication can be applied. However, medication impacts the whole body, resulting in side effects in organs which are not affected by the disease itself. It would make great sense to treat pathological processes, and in particular cells and organs, on the nanometre scale with tools of the same size directly at the location of their origin.
Modern medicine has achieved a lot already, but only a few medical problems are fully solved:
Arteriosclerosis still causes heart attacks and strokes leading to suffering, long-term care and premature death; cancer diseases can be treated more easily than several years ago, but at the price of side effects, which oftrn are of severe nature; infections such as malaria still cause death to a million children in Africa each year; patients with brain diseases often lose their autonomy in everyday life and require nursing care; and finally, diabetes is on the rise worldwide. Innovative medical methods for these and other diseases are therefore desperately needed.
Nanoscience can be characterised by its tools and methods:
- Nanomaterials and nanosurfaces
- Nanosystems and nanorobotics
Nanofluidics / laboratory diagnostics
The miniaturisation of diagnostic tests based on substance measurement in fluids provides crucial benefits. Sample quantities e.g. in the case of blood samples from premature babies or patients under intensive care as well as reagent quantities required for testing can be drastically reduced. Multiple parameters can be tested simultaneously during one test. Special tests performed on a surface are faster than those performed in fluids because the diffusion distance of measured molecules is shorter.
The extreme sensitivity of the cantilever in terms of mechanic deflection can be used for its application as a sensor. For this purpose, the cantilever is covered on its surface with a reactive layer. As soon as the measured molecules come in contact with this layer, the surface properties change minimally, leading to a tiny deflection, which nevertheless can be measured in a very accurate way.
The great variety of eligible layers e.g. simple polymers with varying chemical makeup, but also antibodies and nucleic acid sequences, make this sensor concept highly versatile.
Nanomedicine as sustainable medicine
One of the features of nanomedicine is the fact that smallest substance quantities can suffice both for diagnostics and treatment purposes, if applied precisely. In research studies, specific therapeutic effects could be reached with the help of substance quantities a hundred times smaller compared to conventional medication. The miniaturisation of diagnostic tests can lead to massive reduction of required chemical reagents as well as equipment and sampling. These characteristics present great opportunities for nanomedicine as a sustainable medicine.