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In this article, we presented a general protocol to prepare biomolecule-immobilized mussel-inspired polydopamine (PDA) coatings to improve the blood compatibility of broad ranges of material surfaces. It needs only a simple immersion of substrates in dopamine solution at alkaline pH to form mussel-inspired PDA coating, and then immersing the PDA coated substrates into biomolecule solution to conjugate biomolecules. XPS, water contact angle analysis, and protein assay confirmed that biomolecules could be successfully coated on several material surfaces, including nylon, cellulose, and polyethersulfone membrane surfaces. For the protein fouling resistance, the bovine serum albumin (BSA) modified surfaces were more effective than the amino acid modified surfaces. And the platelet adhesion on the BSA-modified material surfaces was obviously depressed. These results indicated that the blood compatibility of the surfaces was improved by the biomacromolecule-immobilized mussel-inspired coating which might be considered as a universal coating to modify a wide variety of materials.

The correlation between the Raman peak shift and the linewidth of porous silicon is studied. The experimental result does not fit with the relationship predicted by the phonon confinement model. By taking into account both the phonon confinement and the effect of strain, the calculated Raman line shape coincides fairly well with the measured spectrum. The built-in strain of porous silicon varies with the porosity of the sample and is on the order of 10−3.

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A pulsed anodic etching method is developed to prepare light-emitting porous silicon. Under the same equivalent etching condition, pulsed etching can yield a more uniform porous silicon film with stronger photoluminescence intensity than the film prepared by ordinary dc etching. The atomic force microscopic observation shows that the porous silicon surface prepared by pulsed etching contains more widely separated Si columns but with steeper sidewalls, which are believed to result in the improvement of quantum confinement. The thickness of pulse etched porous silicon film is found to be much larger than that of a dc etched sample.

Contamination of heavy metal in wastewater has caused great concerns on human life and health. Developing an efficient material to eliminate the heavy metal ions has been a popular topic in recent years. In this work, sulfonated cellulose (SC) was explored as efficient adsorbent for metal ions in solution. Thermo gravimetric analyzer (TGA), X-ray diffraction (XRD) and Fourier-transform infrared spectrometer (FTIR) first analyzed the characterizations of SC. Subsequently, effects of solution pH, adsorbent loading, temperature and initial metal ion concentration on adsorption performance were investigated. The results showed that sulfonated modification of cellulose could decrease the crystallinity and thermostability of cellulose. Due to its excellent performance of adsorption to metal ions, SC could reach adsorption equilibrium status within as short as 2min. In multi-component solution, SC can orderly removes Fe(3+), Pb(2+) and Cu(2+) with excellent selectivity and high efficiency. In addition, SC is a kind of green and renewable adsorbent because it can be easily regenerated by treatment with acid or chelating liquors. The mechanism study shows that the sulfonic group play a major role in the adsorption process.

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