Biomedical Engineering Reference
In-Depth Information
Part II
Material Design and Selection I
This section focuses specifically on a discussion of materials that form the basis of the bio-
logical sensing layer in biosensors. In Chapter 7, Amarjeet Bassi reviews some examples
of approaches that combine either the “passive” materials or stimuli-responsive materials
within the biological sensing component. This chapter discusses the application of such
materials that make up the sensing layer in biosensors and presents the state of the art in
these areas. First some recent studies on cantilever biosensors are discussed. Then other
types of “smart” materials including dendrimers, conducting films and gels, and stimuli-
responsive materials are considered. Several techniques have been utilized in biosensor
design for forming the biological sensing layer. The deposition of single layers on the
biosensor surface offers the opportunity of careful control and design of surface proper-
ties. In Chapter 8, Professor Shin-ichiro Suye and Haitao Zheng describe the layer-by-layer
(LBL) adsorption technique based on electrostatic force between polyelectrolytes and pro-
teins. This method can produce thin multicomponent layers by alternate adsorption in
cationic and anionic polyelectrolytes. The characterization of the layers using QCM and
AFM is described. In Chapter 9, Professor Claudio Nicolini, Manuela Adami, and
Christina Paternolli have summarized the present state of the art on nanostructuring of
sensing organic matrices and their applications in biosensor design for health and envi-
ronment. Several applications are discussed such as Potentiometric Stripping Analyzer for
metal detection using neural networks, nanotube biosensors for HCl detection,
cytochromes on nanoparticles or as thin films, bacteriorhodopsin thin films for anesthetic
detection, and nanocomposites for gas sensing. In Chapter 10, Professor Shekhar Bhansali
and others discuss the concept of a bioengineered interface that interacts directly with skin
layers using microfluidics-based sensing systems. There is sufficient background on the
structure of skin and its layers. The design of MEMS devices that interface with the skin is
discussed next. Techniques for information gathering such as electrochemical microelec-
trodes are covered. Several issues involved in microelectrode design, testing, and imple-
mentation are covered. The microfluidic system contains sensor arrays integrated with
local computing and communication systems. Thus, this “smart” biosensor technology
can provide real-time information on a minimally invasive platform.
