In 2000 we are turning from the century of physics to the century of biology. Transgenetic food, genetic diagnostics and pharmaceuticals in medicine biology and biochemistry weekly confront us with new findings giving rise to new opportunities. By Dr Heidrun Tippe.
The very dynamic development of both products and market participants demands new solutions in analytics. This is where physics is now asked to apply its vast experience in industrial measurement techniques to life sciences. There is a high demand for new measurement devices, eg to follow the kinetics of biochemical reactions, for the approval of DNA biochips, for analysing immunoreactions or blood parameters and for pharmacological screening.
In addition to very specific fields of research in life sciences, there is a growing industrial demand for routine and high throughput screening systems.
Fraunhofer IPM, a German contract researcher concentrating on the development of physical measurement techniques and their transfer into industry be it prototype stage or complete system ready for installation has turned to analytical tasks in life sciences as a result of its applied research in lab and process monitoring. On the basis of its experience and competence in micro system technology and optical measurement techniques, Fraunhofer IPM now develops solutions for a variety of bio-analytical tasks.
In medical diagnostics, food analysis and many areas of basic research, screening on the basis of biochip technology carries a large potential in particular for routine analysis. Nucleic acid analytics enables the detection of trans-genetic substances in food, blood analytics of various parameters,and quality control wherever the composition of DNA/RNA is crucial.
Higher demands in efficiency standards ask for fast, reliable and cost-effective screening methods. A high number of simultaneous reactions to be detected in real-time and high sensitivity are of major importance. The IPM Biochip Reader meets these requirements (Fig. 1.) One type of the fluorescence reader is already commercially available. The most remarkable features of this system are its capacity for parallel measurement (currently up to 5000 measuring dots) and its user-friendly design.
Be it for bedside analysis or out-patient nursing, medical care asks for fast, easy and highly accurate systems. Due to tighter security standards for blood storage, additional fast and easy tests are to be expected. Fraunhofer IPM develops various adjustments of a thin-film interferometer which reveals the kinetics of reactions and registers the multi-molecular interactions based on antibody-antigen-binding.
The Interferometric Biosensor IBS 101 can be used for affinity measurements as well as for concentration detection in diagnostics and quality control. It can be applied both as a stand-alone device in a surgery or in combination with other analytic systems, for the supervision of cell cultures, for phytohormone analysis, or for process monitoring. Its label free analysis guarantees a minimum of reagents and working steps and thus meets the requirements of a continually expanding market. IBS 101 key components include a bio-monitoring glass chip
(Fig. 2) and an integrated optical Y-distributor (Fig. 3) increases the accuracy of the measurement as well as its velocity. Parameters relevant for medical analysis are detected in real time, for instance while seeing the doctor. The device performs at very low operating costs. In comparison to other label-free systems, it achieves a higher resolution of mass-dotting while the hissing sounds are clearly reduced.
A direct recording of a living cell's signals and thus of the astatus quo' of the cell is asked for in bio-monitoring. It should provide evidence about the influences the cell has been exposed to. In addition, a specific sensitivity of a cell alignment towards certain reagents is to be measured. In co-operation with partners from industry and science, IPM has designed an impedance spectroscopic sensor chip. This chip measures cellular reactions directly on living cells. Over several days, the multi sensor chip records the various cell signals simultaneously while being online. Currently, the most prominent field of possible application lies in cancer research.
The efficiency of chemo-therapy drugs, ie the selection of the optimal individual therapy, is evaluated according to biopsy samples of each patient. Semi-conductor sensors working online in long-term measurement offer the possibility of a distinctive reduction of drugs given and of the time patients spend in hospital. The application in pharmascreening proves efficient as it can significantly cut the time for preparation of clinical tests. With regard to bio-compatibility the system also opens up new possibilities in transplantation medicine.
New monitoring and analytical demands keep emerging from the life sciences. Physics experts are looking forward to meeting the challenge.
ENQUIRY No 36
Dr Heidrun Tippe is with Fraunhofer IPM, Freiburg, Germany.
