compounds have been identified in regions far from the highly populate regions
such as Arctic regions [9]. These finding underlines once more that PPCPs are a real
global concern.
Prioritization of PCPPs pollutants and development of specific water monitoring
systems is mandatory to control the PCPP level in order to determine their effects
due to long term exposure.
2 3-0 Biosensors: A Brief Outline
A detailed description of biosensor architecture can be easily found in literature
[10]. It is important to recall some element of these analytical system in order to
better understand the role of nucleic-acids. A biosensor is defined as an analytical
system combining a biological or bio-inspired component and a physico-chemical
detector. The standard architecture of a biosensor includes several specialized
modules: (a) a bio-receptor element; (b) a transducer system (c) an electronic
module to amplify, process and visualize the acquired signal. Two are the compulsory features of a biosensor: the recognition element must have a biological
origin or must be biologically inspired and the transducer material which transform
the signal coming from the sensing element into another on (optical, piezoelectric,
electro-chemical, electro-chemiluminescence etc.). The bio-receptor is the responsible of analyte sensing by molecular recognition. Molecular recognition identifies
the elementary processes that lead the specific binding that occur between two or
more molecules by non-covalent bonds such in the case of protein-protein interaction or enzyme substrate binding [11].
The signal, resulting in the interaction between the analyte and the probe, is
transformed into a standard signal that can be captured by standard analytical
methods. A bio-receptor has to be linked to a transducer surface. The simple way is
to immobilize the probe on a surface or particle. Immobilization can be achieve by
different methods; (i) adsorption; (ii) covalent bonds, (iii) crosslinking; (iv) entrapment. The signal, coming from the receptor-ligand interaction, can be measured
in a direct or indirect manner; the first method records data during the time course
of binding kinetic, the latter record only the variations that occur at the end of the
process. Bio-recognition elements are roughly grouped into three different set:
natural, semi-synthetic and synthetic. Proteins, as well enzymes as antibodies, are
the widely used as natural elements in biosensor development; they s how a very
high steric selectivity and the binding can be determined using different type of
transducers. The semi-synthetic receptors require a partial laboratory synthesis to
obtain the optimal specificity for a particular ligand. Nucleic Acids are included in
this group. Totally synthetic bio-receptors are usually produced using or not a
biological template. Molecularly imprinted polymers (MIPs) belong to this class of
synthetic receptors. The template of a MIP can be a biological macromolecule or
other organic compounds. At the end of polymerization process the template is
removed and the resulting polymeric structure is able to recognize specific ligands.
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P. Arrigo and D. Baroni
such as Arctic regions [9]. These finding underlines once more that PPCPs are a real
global concern.
Prioritization of PCPPs pollutants and development of specific water monitoring
systems is mandatory to control the PCPP level in order to determine their effects
due to long term exposure.
2 3-0 Biosensors: A Brief Outline
A detailed description of biosensor architecture can be easily found in literature
[10]. It is important to recall some element of these analytical system in order to
better understand the role of nucleic-acids. A biosensor is defined as an analytical
system combining a biological or bio-inspired component and a physico-chemical
detector. The standard architecture of a biosensor includes several specialized
modules: (a) a bio-receptor element; (b) a transducer system (c) an electronic
module to amplify, process and visualize the acquired signal. Two are the compulsory features of a biosensor: the recognition element must have a biological
origin or must be biologically inspired and the transducer material which transform
the signal coming from the sensing element into another on (optical, piezoelectric,
electro-chemical, electro-chemiluminescence etc.). The bio-receptor is the responsible of analyte sensing by molecular recognition. Molecular recognition identifies
the elementary processes that lead the specific binding that occur between two or
more molecules by non-covalent bonds such in the case of protein-protein interaction or enzyme substrate binding [11].
The signal, resulting in the interaction between the analyte and the probe, is
transformed into a standard signal that can be captured by standard analytical
methods. A bio-receptor has to be linked to a transducer surface. The simple way is
to immobilize the probe on a surface or particle. Immobilization can be achieve by
different methods; (i) adsorption; (ii) covalent bonds, (iii) crosslinking; (iv) entrapment. The signal, coming from the receptor-ligand interaction, can be measured
in a direct or indirect manner; the first method records data during the time course
of binding kinetic, the latter record only the variations that occur at the end of the
process. Bio-recognition elements are roughly grouped into three different set:
natural, semi-synthetic and synthetic. Proteins, as well enzymes as antibodies, are
the widely used as natural elements in biosensor development; they s how a very
high steric selectivity and the binding can be determined using different type of
transducers. The semi-synthetic receptors require a partial laboratory synthesis to
obtain the optimal specificity for a particular ligand. Nucleic Acids are included in
this group. Totally synthetic bio-receptors are usually produced using or not a
biological template. Molecularly imprinted polymers (MIPs) belong to this class of
synthetic receptors. The template of a MIP can be a biological macromolecule or
other organic compounds. At the end of polymerization process the template is
removed and the resulting polymeric structure is able to recognize specific ligands.
216
P. Arrigo and D. Baroni