Chitosan-templated bio-coloration of cotton fabrics via laccase-catalyzed polymerization of hydroquinone

There is an increasing interest in the development of enzymatic coloration of textile fabrics as an alternative to conventional textile dyeing processes, which is successful for dyeing protein fibers. However, unmodified cotton fabrics are difficult to be dyed through enzyme catalysis due to the lack of affinity of biosynthesized dyes to cotton fibers. In order to improve the enzyme-catalyzed dyeability of cotton fibers, chitosan was used to coat cotton fabrics as template. A novel and facile bio-coloration technique using laccase catalysis of hydroquinone was developed to dye chitosan-templated cotton fabrics. The polymerization of hydroquinone with the template of chitosan under the laccase catalysis was monitored by ultraviolet-vis spectrophotometer on the absorbance of reaction solution. A significant peak of UV-vis spectrum at 246 nm corresponding to large conjugated structures appeared and increased with increasing the duration of enzymatic catalysis. The effect of different treatment conditions on the laccase-catalyzed dyeing of cotton fabric was investigated to determine their optimal parameters of laccase-catalyzed coloration. Fourier-transform infrared spectroscopy spectra demonstrated the formation of H-bond and Schiff base reaction between chitosan and polymerized hydroquinone. Scanning electron microscopy indicated that the surface of dyed cotton fiber was much rougher than that of the control sample. Moreover, X-ray photoelectron spectroscopy also revealed the existence of the chitosan/polymerized hydroquinone complex and polymerized hydroquinone on the dyed cotton fibers. This chitosan-templated approach offers possibility for biological dyeing coloration of cotton fabrics and other cellulosic materials.

Molecular imprinting science and technology: a survey of the literature for the years 2004-2011

Herein, we present a survey of the literature covering the development of molecular imprinting science and technology over the years 2004-2011. In total, 3779 references to the original papers, reviews, edited volumes and monographs from this period are included, along with recently identified uncited materials from prior to 2004, which were omitted in the first instalment of this series covering the years 1930-2003. In the presentation of the assembled references, a section presenting reviews and monographs covering the area is followed by sections describing fundamental aspects of molecular imprinting including the development of novel polymer formats. Thereafter, literature describing efforts to apply these polymeric materials to a range of application areas is presented. Current trends and areas of rapid development are discussed.