**Acknowledgments**

Several measurements of the intermolecular force produced by biomolecular interaction were reported, i.e. the AFM surface topography of phospholipids LB films have shown a smooth surface. In presence of protein in LB film well-defined structures were observed, characterized by domains, globules, grains with different diameters. The images indicates that both enzyme molecules are not only properly entrapped in the composite membrane but also well exposed at the surface, which can be clearly seen in Figure 10. The recorded images show a relatively high homogeneity of the topography, especially in case of lipid

The advances observed in the areas of biochemistry, chemistry, electronics and bioelectron‐ ics will markedly influence future of biosensor production. Progresses in biosensors technol‐ ogy focus on two main aspects: transducer technology development and sensing element development [111]. New improved detection systems developed under the areas of micro‐ electronics or even nanoelectronics can be used in biosensors. However, since biosensor sen‐ sitivity and selectivity depend basically on the properties of the biorecognition elements, a crucial aspect in future biosensors is the development of improved molecular recognition el‐ ements. In this respect, biotechnology and genetic engineering offer the possibility of tailor

According to fact, that miniaturization of devices as well as multi-sensor arrays are expected to have a marked impact in biosensors technology, the use of thin film methods for prepara‐ tion of the recognition layers provides a simple procedure for the functionalization of elec‐ trode surfaces using nanogram amounts of material. Different techniques can give either highly ordered or amorphous film, ensured a high level of control of the environment and often resemble the environment found inside biomembranes, thereby guaranteed the stabili‐ zation of biomolecules. Biosensors produced using these layer technologies can display high sensitivities, be easily interrogated using electronic, optical or mass-sensitive techniques, can

Another current trend is the combination of physics and biology in the creation of new nanostructures. Nanotechnology comprises a group of emerging techniques from physics, chemistry, biology, engineering and microelectronics that are capable of manipulating mat‐ ter at nanoscale. This novel technology bridges materials science, and biochemistry/chemis‐ try, where individual molecules are of major interest [112]. Inspired by nature, molecular self-assembly has been proposed for the synthesis of nanostructures capable to perform unique functions. According to that, novel tools that combine different sensing methods can provide also the necessary complementary information that is needed to understand the limitations and to optimize the performance of the new techniques. Therefore, introducing existing methods (e.g., SPR, QCM, ellipsometry) allow parallel complementary investiga‐ tions of the biochemical processes that take place at the interface between the devices and

film [17].

**7. Prospects and future trends**

56 State of the Art in Biosensors - General Aspects

binding molecules with predefined properties

often be regenerated and display good stability.

the biological sample.

The authors are gratefully acknowledged to Wroclaw University of Technology and Polish National Centre of Progress of Explorations for the financial support (Grant no. NR05-0017-10/2010).
