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Biomimetic strategies for sensing biological species.

Hussain M, Wackerlig J, Lieberzeit PA - Biosensors (Basel) (2013)

Bottom Line: A different strategy comprises of devising polymer coatings to change the biocompatibility of surfaces that can also be used to immobilized natural receptors/ligands and thus stabilize them.Rationally speaking, this leads to self-assembled monolayers closely resembling cell membranes, sometimes also including bioreceptors.It mainly focuses on the literature published since 2005.

View Article: PubMed Central - PubMed

Affiliation: Department of Analytical Chemistry, University of Vienna, Waehringer Strasse 38, A-1090, Vienna, Austria; E-Mails: munawar_arif@hotmail.com (M.H.); judith.maehner@univie.ac.at (J.W.).

ABSTRACT
The starting point of modern biosensing was the application of actual biological species for recognition. Increasing understanding of the principles underlying such recognition (and biofunctionality in general), however, has triggered a dynamic field in chemistry and materials sciences that aims at joining the best of two worlds by combining concepts derived from nature with the processability of manmade materials, e.g., sensitivity and ruggedness. This review covers different biomimetic strategies leading to highly selective (bio)chemical sensors: the first section covers molecularly imprinted polymers (MIP) that attempt to generate a fully artificial, macromolecular mold of a species in order to detect it selectively. A different strategy comprises of devising polymer coatings to change the biocompatibility of surfaces that can also be used to immobilized natural receptors/ligands and thus stabilize them. Rationally speaking, this leads to self-assembled monolayers closely resembling cell membranes, sometimes also including bioreceptors. Finally, this review will highlight some approaches to generate artificial analogs of natural recognition materials and biomimetic approaches in nanotechnology. It mainly focuses on the literature published since 2005.

No MeSH data available.


The structure of the amino modified CdSe/ZnS core-shell QD (a) and the size distribution of the QDs (b) in the aqueous environment of living cells. The averaged diameter of the QD is 15.0 ± 0.8 nm. Reprinted with permission from [54], © 2011 Elsevier.
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biosensors-03-00089-f009: The structure of the amino modified CdSe/ZnS core-shell QD (a) and the size distribution of the QDs (b) in the aqueous environment of living cells. The averaged diameter of the QD is 15.0 ± 0.8 nm. Reprinted with permission from [54], © 2011 Elsevier.

Mentions: Being a comparably new class of nanomaterials, quantum dots (QDs) are considered to be promising matrices for sensor layers. For example, employing QDs as biomimetic material, Huang et al. [54] developed a technique for quantitative visualization of the surface charge on biological cells with nano-scale resolution. The QDs were generated by using amino modified CdSe/ZnS nanoparticles (as seen in Figure 9(a)) altered by modular ligands based on poly(ethylene) coupled with amino to enhance their stability and biocompatibility. This modification leads to positively charged QDs with a diameter of about 15 nm (Figure 9(b)). The charge densities of different kinds of cells from normal to mutant have been detected by employing wide-field optical sectioning microscopy for 2D/3D imaging of the QD-labeled cells. The surface charge distribution is important for analysis of structure, function, biological behavior and malignant transformation of cells. Similarly, Wu et al. [55] applied QDs for the development of highly sensitive molecular beacon (MB) for DNA sensing. Figure 10 summarizes the functionalization of QDs and the principal setup of the QD based molecular beacon. Each beacon consists of a “smart probe” which quenches the fluorescence in the absence of the target DNA. The onset of fluorescence emission thereby, indicates the presence of target DNA (Figure 10(b)). In this case, the QD approach allows for substantially increased quencher densities, as compared to flat surfaces and thus increased signals. A possible combination of NPs and QDs is demonstrated by Xie et al. [56]. Fe2O3 magnetic nanoparticles and fluorescent quantum dots were embedded together into single swelling poly(styrene/acrylamide) copolymer nanospheres. In this way, fluorescent-magnetic bifunctional nanospheres can be generated. Their approach included the fabrication of smart wheat germ agglutinin (WGA)- trifunctional nanobiosensors (TFNS), peanut agglutinin (PNA)-TFNS and Dolichos biflorus agglutinin (DBA)-TFNS composites that combine high fluorescence yield, magnetic properties and selective detection of N-acetylglucosamine, D-galactosamine and N-acetylgalactosamine residues on the A549 cell surface. Such biomimetic lectin-modified nano biosensors (lectin-TFNS) can thus be employed for analysis of glycoconjugates on A549 cell surface.


Biomimetic strategies for sensing biological species.

Hussain M, Wackerlig J, Lieberzeit PA - Biosensors (Basel) (2013)

The structure of the amino modified CdSe/ZnS core-shell QD (a) and the size distribution of the QDs (b) in the aqueous environment of living cells. The averaged diameter of the QD is 15.0 ± 0.8 nm. Reprinted with permission from [54], © 2011 Elsevier.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4263596&req=5

biosensors-03-00089-f009: The structure of the amino modified CdSe/ZnS core-shell QD (a) and the size distribution of the QDs (b) in the aqueous environment of living cells. The averaged diameter of the QD is 15.0 ± 0.8 nm. Reprinted with permission from [54], © 2011 Elsevier.
Mentions: Being a comparably new class of nanomaterials, quantum dots (QDs) are considered to be promising matrices for sensor layers. For example, employing QDs as biomimetic material, Huang et al. [54] developed a technique for quantitative visualization of the surface charge on biological cells with nano-scale resolution. The QDs were generated by using amino modified CdSe/ZnS nanoparticles (as seen in Figure 9(a)) altered by modular ligands based on poly(ethylene) coupled with amino to enhance their stability and biocompatibility. This modification leads to positively charged QDs with a diameter of about 15 nm (Figure 9(b)). The charge densities of different kinds of cells from normal to mutant have been detected by employing wide-field optical sectioning microscopy for 2D/3D imaging of the QD-labeled cells. The surface charge distribution is important for analysis of structure, function, biological behavior and malignant transformation of cells. Similarly, Wu et al. [55] applied QDs for the development of highly sensitive molecular beacon (MB) for DNA sensing. Figure 10 summarizes the functionalization of QDs and the principal setup of the QD based molecular beacon. Each beacon consists of a “smart probe” which quenches the fluorescence in the absence of the target DNA. The onset of fluorescence emission thereby, indicates the presence of target DNA (Figure 10(b)). In this case, the QD approach allows for substantially increased quencher densities, as compared to flat surfaces and thus increased signals. A possible combination of NPs and QDs is demonstrated by Xie et al. [56]. Fe2O3 magnetic nanoparticles and fluorescent quantum dots were embedded together into single swelling poly(styrene/acrylamide) copolymer nanospheres. In this way, fluorescent-magnetic bifunctional nanospheres can be generated. Their approach included the fabrication of smart wheat germ agglutinin (WGA)- trifunctional nanobiosensors (TFNS), peanut agglutinin (PNA)-TFNS and Dolichos biflorus agglutinin (DBA)-TFNS composites that combine high fluorescence yield, magnetic properties and selective detection of N-acetylglucosamine, D-galactosamine and N-acetylgalactosamine residues on the A549 cell surface. Such biomimetic lectin-modified nano biosensors (lectin-TFNS) can thus be employed for analysis of glycoconjugates on A549 cell surface.

Bottom Line: A different strategy comprises of devising polymer coatings to change the biocompatibility of surfaces that can also be used to immobilized natural receptors/ligands and thus stabilize them.Rationally speaking, this leads to self-assembled monolayers closely resembling cell membranes, sometimes also including bioreceptors.It mainly focuses on the literature published since 2005.

View Article: PubMed Central - PubMed

Affiliation: Department of Analytical Chemistry, University of Vienna, Waehringer Strasse 38, A-1090, Vienna, Austria; E-Mails: munawar_arif@hotmail.com (M.H.); judith.maehner@univie.ac.at (J.W.).

ABSTRACT
The starting point of modern biosensing was the application of actual biological species for recognition. Increasing understanding of the principles underlying such recognition (and biofunctionality in general), however, has triggered a dynamic field in chemistry and materials sciences that aims at joining the best of two worlds by combining concepts derived from nature with the processability of manmade materials, e.g., sensitivity and ruggedness. This review covers different biomimetic strategies leading to highly selective (bio)chemical sensors: the first section covers molecularly imprinted polymers (MIP) that attempt to generate a fully artificial, macromolecular mold of a species in order to detect it selectively. A different strategy comprises of devising polymer coatings to change the biocompatibility of surfaces that can also be used to immobilized natural receptors/ligands and thus stabilize them. Rationally speaking, this leads to self-assembled monolayers closely resembling cell membranes, sometimes also including bioreceptors. Finally, this review will highlight some approaches to generate artificial analogs of natural recognition materials and biomimetic approaches in nanotechnology. It mainly focuses on the literature published since 2005.

No MeSH data available.