Thermally stable cellulose nanospheres prepared from office waste paper by complete removal of hydrolyzed sulfate groups.

Cellulose nanocrystals are commonly obtained by acid hydrolysis, particularly with HSO. However, a small amount of deposited sulfate-groups contributes to the degradation of their thermal stability. This study prepared thermally-stable and sulfate-group-free cellulose nanospheres (CNSs) from office waste paper by HSO hydrolysis followed by solvolytic desulfation.

Synthesis of cellulose-g-poly(acrylic acid) with high water absorbency using pineapple-leaf extracted cellulose fibers.

This study synthesized cellulose-g-poly(acrylic acid) with high water absorbency using the cellulose extracted from pineapple leaves. The synthesis experiment used a novel combination of ethylene glycol dimethacrylate (EGDMA) and azobisisobutyronitrile (AIBN) as the cross-linker and the initiator, respectively. Experimental results showed that the concentrations of AIBN and EGDMA had significant effects on the structure and the water absorbency of the cross-linked materials.

Preparation of chitosan/hydroxyapatite substrates with controllable osteoconductivity tracked by AFM.

In this study, cell-material adhesive strength and cellular mechanical properties were measured using atomic force microscopy (AFM) to track cell attachment and osteogenic differentiation. First, chitosan substrates were treated with simulated body fluid (SBF) for various periods, resulting in substrates with different osteoconductivity. The X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS) and in vitro tests revealed that the biomimeticity and osteoconductivity of substrates increased with increasing time of SBF treatment.

Immobilization of naringin onto chitosan substrates by using ozone activation.

Ozone oxidation can easily produce peroxides containing active free radicals that can be used for the surface modification of biomaterials. This process is highly efficient and nontoxic. In this research, naringin, an HMG-CoA reductase inhibitor that can promote bone formation, was immobilized onto a chitosan film using ozone activation.

Interactions between chitosan and cells measured by AFM.

Chitosan, a biocompatible material that has been widely used in bone tissue engineering, is believed to have a high affinity to osteoblastic cells. This research is the first to prove this hypothesis. By using atomic force microscopy (AFM) with a chitosan-modified cantilever, quantitative evaluation of the interforce between chitosan and cells was carried out.