Polydiacetylenes color change

A robust polydiacetylene/silica composite has recently been prepared that undergoes a color change in response to thermal, chemical, and mechanical stimuli (39). This new hybrid material holds considerable promise for the fabrication of new devices. 

Additional soluble polydiacetylenes have been discovered which show temperature- or solvent-induced color changes with absorption shifts similar to poly4BCMU(6-8). These solutions are believed to... 

Charych et al. reported a direct colorimetric assay for the detection of influenza virus, using a polydiacetylene bilayer immobilized on a glass microscope slide and functionalized with sialic acid (the vims receptor molecule). Upon binding of the vims, a color change is visible to the naked eye, but could also be quantified by absorption spectroscopy. The authors demonstrated by physical characterization that the packing of the bilayer with bound vims was different from that without vims, resulting in a change of the optical properties of the polymer backbone. 

Figure 27 Photopolymerization of the precursor with an embedded butadyine moiety leads to a blue-colored polydiacetylene material (a) analyte binding to the receptor or affinity moiety (red pentagon) results in a change in the polydiacetylene conjugated backbone and shift of absorption spectra from blue to red and (b) photographs of wells comprising solution Zn(dipicolylamine)2 containing liposome (0.25 mM) and various sodium salts anions (0.25 mM) in HEPES buffer, pH = 7. (Adapted from Ref. 126. Wiley-VCH, 2011.)...

N. Mino, H. Tamura, and K. Ogawa, Analysis of color transitions and changes on Langmuir-Blodgett films of a polydiacetylene derivative, Langmuir 7 2336 (1991). 

Substituted polydiacetylenes form a unique class of conjugated polymers. A decade ago substituted polydiacetylenes have been solubilized and shown various color transition either by changing the solvent quality or the temperature. This has been the origin of a growing intoest on the solution of conjugated polymers (17). 

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