Synthetic materials capable of selectively recognizing proteins are important in separations, biosensors and the development of biomedical materials. The technique of molecular imprinting creates specific recognition sites in polymers by using template molecules. Molecular recognition is attributed to binding sites that complement molecules in size, shape and chemical functionality. But attempts to imprint proteins have met with only limited success. Here we report a method for imprinting surfaces with protein-recognition sites. We use radio-frequency glow-discharge plasma deposition to form polymeric thin films around proteins coated with disaccharide molecules. The disaccharides become covalently attached to the polymer film, creating polysaccharide-like cavities that exhibit highly selective recognition for a variety of template proteins, including albumin, immunoglobulin G, lysozyme, ribonuclease and streptavidin. Direct imaging of template recognition is achieved by patterning a surface at the micrometre scale with imprinted regions.

A series of renewable bis(cyanate) esters have been prepared from bisphenols synthesized by condensation of 2-methoxy-4-methylphenol (creosol) with formaldehyde, acetaldehyde, and propionaldehyde. The cyanate esters have been fully characterized by infrared spectroscopy, (1)H and (13)C NMR spectroscopy, and single crystal X-ray diffraction. These compounds melt from 88 to 143 °C, while cured resins have glass transition temperatures from 219 to 248 °C, water uptake (96 h, 85 °C immersion) in the range of 2.05-3.21%, and wet glass transition temperatures from 174 to 193 °C. These properties suggest that creosol-derived cyanate esters may be useful for a wide variety of military and commercial applications. The cure chemistry of the cyanate esters has been studied with FTIR spectroscopy and differential scanning calorimetry. The results show that cyanate esters with more sterically demanding bridging groups cure more slowly, but also more completely than those with a bridging methylene group. In addition to the structural differences, the purity of the cyanate esters has a significant effect on both the cure chemistry and final Tg of the materials. In some cases, post-cure of the resins at 350 °C resulted in significant decomposition and off-gassing, but cure protocols that terminated at 250-300 °C generated void-free resin pucks without degradation. Thermogravimetric analysis revealed that cured resins were stable up to 400 °C and then rapidly degraded. TGA/FTIR and mass spectrometry results showed that the resins decomposed to phenols, isocyanic acid, and secondary decomposition products, including CO2. Char yields of cured resins under N2 ranged from 27 to 35%, while char yields in air ranged from 8 to 11%. These data suggest that resins of this type may potentially be recycled to parent phenols, creosol, and other alkylated creosols by pyrolysis in the presence of excess water vapor. The ability to synthesize these high temperature resins from a phenol (creosol) that can be derived from lignin, coupled with the potential to recycle the composites, provides a possible route to the production of sustainable, high-performance, thermosetting resins with reduced environmental impact.

We have developed an improved method of straightening DNA molecules for use in optical restriction mapping. The DNA was straightened on 3-aminopropyltriethoxysilane-coated glass slides using surface tension generated by a moving meniscus. In our method the meniscus motion was controlled mechanically, which provides advantages of speed and uniformity of the straightened molecules. Variation in the affinity of the silanized surfaces for DNA was compensated by precoating the slide with single-stranded non-target blocking DNA. A small amount of MgCl2 added to the DNA suspension increased the DNA-surface affinity and was necessary for efficient restriction enzyme digestion of the straightened surface-bound DNA. By adjusting the amounts of blocking DNA and MgCl2, we prepared slides that contained many straight parallel DNA molecules. Straightened lambda phage DNA (48 kb) bound to a slide surface was digested by EcoRI restriction endonuclease, and the resulting restriction fragments were imaged by fluorescence microscopy using a CCD camera. The observed fragment lengths showed excellent agreement with their predicted lengths.