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Chemomechanical Polymers as Sensors and Actuators for Biological and Medicinal Applications.

Schneider HJ, Kato K, Strongin RM - Sensors (Basel) (2007)

Bottom Line: Two different effector molecules can induce motions as functions of their concentration, thus representing a logical AND gate.Another principle relies on the fast formation of covalent bonds between an effector and the chemomechanical polymer.The speed of the responses can significantly increase by increasing the surface to volume ratio of the polymer particles.

View Article: PubMed Central - PubMed

Affiliation: FR Organische Chemie der Universität des Saarlandes, D-66041 Saarbrücken, Germany.

ABSTRACT
Changes in the chemical environment can trigger large motions in chemomechanical polymers. The unique feature of such intelligent materials, mostly in the form of hydrogels, is therefore, that they serve as sensors and actuators at the same time, and do not require any measuring devices, transducers or power supplies. Until recently the most often used of these materials responded to changes in pH. Chemists are now increasingly using supramolecular recognition sites in materials, which are covalently bound to the polymer backbone. This allows one to use a nearly unlimited variety of guest (or effector) compounds in the environment for a selective response by automatically triggered size changes. This is illustrated with non-covalent interactions of effectors comprising of metal ions, isomeric organic compounds, including enantiomers, nucleotides, aminoacids, and peptides. Two different effector molecules can induce motions as functions of their concentration, thus representing a logical AND gate. This concept is particularly fruitful with effector compounds such as peptides, which only trigger size changes if, e.g. copper ions are present in the surroundings. Another principle relies on the fast formation of covalent bonds between an effector and the chemomechanical polymer. The most promising application is the selective interaction of covalently fixed boronic acid residues with glucose, which renders itself not only for sensing, but eventually also for delivery of drugs such as insulin. The speed of the responses can significantly increase by increasing the surface to volume ratio of the polymer particles. Of particular interest is the sensitivity increase which can be reached by downsizing the particle volume.

No MeSH data available.


Structures of some chemomechanical polymers (I: polymethacrylic acid with supramolecular binding functions, II: chitosam, III: polyallylamine).
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f16-sensors-07-01578: Structures of some chemomechanical polymers (I: polymethacrylic acid with supramolecular binding functions, II: chitosam, III: polyallylamine).

Mentions: In hydrogels (Scheme 2) a volume increase occurs by the uptake of water which is needed for the solvation of developing cationic or anionic sites, which is invariably accompanied by the import of the associated counterions (see also Scheme 1). In polyelectrolyte gels, swelling and contraction can also be produced electrically (as in electrodialysis), thus allowing the design of both pH-operated and microelectro-machines [21]. Several chemomechanical elements in particular for pH sensing have been already described [22].


Chemomechanical Polymers as Sensors and Actuators for Biological and Medicinal Applications.

Schneider HJ, Kato K, Strongin RM - Sensors (Basel) (2007)

Structures of some chemomechanical polymers (I: polymethacrylic acid with supramolecular binding functions, II: chitosam, III: polyallylamine).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3814870&req=5

f16-sensors-07-01578: Structures of some chemomechanical polymers (I: polymethacrylic acid with supramolecular binding functions, II: chitosam, III: polyallylamine).
Mentions: In hydrogels (Scheme 2) a volume increase occurs by the uptake of water which is needed for the solvation of developing cationic or anionic sites, which is invariably accompanied by the import of the associated counterions (see also Scheme 1). In polyelectrolyte gels, swelling and contraction can also be produced electrically (as in electrodialysis), thus allowing the design of both pH-operated and microelectro-machines [21]. Several chemomechanical elements in particular for pH sensing have been already described [22].

Bottom Line: Two different effector molecules can induce motions as functions of their concentration, thus representing a logical AND gate.Another principle relies on the fast formation of covalent bonds between an effector and the chemomechanical polymer.The speed of the responses can significantly increase by increasing the surface to volume ratio of the polymer particles.

View Article: PubMed Central - PubMed

Affiliation: FR Organische Chemie der Universität des Saarlandes, D-66041 Saarbrücken, Germany.

ABSTRACT
Changes in the chemical environment can trigger large motions in chemomechanical polymers. The unique feature of such intelligent materials, mostly in the form of hydrogels, is therefore, that they serve as sensors and actuators at the same time, and do not require any measuring devices, transducers or power supplies. Until recently the most often used of these materials responded to changes in pH. Chemists are now increasingly using supramolecular recognition sites in materials, which are covalently bound to the polymer backbone. This allows one to use a nearly unlimited variety of guest (or effector) compounds in the environment for a selective response by automatically triggered size changes. This is illustrated with non-covalent interactions of effectors comprising of metal ions, isomeric organic compounds, including enantiomers, nucleotides, aminoacids, and peptides. Two different effector molecules can induce motions as functions of their concentration, thus representing a logical AND gate. This concept is particularly fruitful with effector compounds such as peptides, which only trigger size changes if, e.g. copper ions are present in the surroundings. Another principle relies on the fast formation of covalent bonds between an effector and the chemomechanical polymer. The most promising application is the selective interaction of covalently fixed boronic acid residues with glucose, which renders itself not only for sensing, but eventually also for delivery of drugs such as insulin. The speed of the responses can significantly increase by increasing the surface to volume ratio of the polymer particles. Of particular interest is the sensitivity increase which can be reached by downsizing the particle volume.

No MeSH data available.