CELL 252 |
| Cellulose nanocrystal-filled polymer composites have drawn attention from researchers since the late 1980s. Cellulose nanocrystals (CNXLs) have been widely recognized as a material with remarkable reinforcing capabilities, excellent mechanical properties, low density and the ability to form composites with thermoplastic and thermoset matrices. An advanced cellulose\polymer hybrid material with no interphase would be a promising step towards designing hierarchical biocomposites. The thermoplasticity and biocompatibility of cellulose-based materials could also be fully explored using this advanced hybrid material. Thus assembling CNXLs into multifunctional nanostructures is one of the key issues in materializing the full potential of these cellulose-polymer hybrid materials. Here we adopt an advanced bottom-up hierarchical approach to self assemble CNXLs using complementary DNA strands as structural linkers. The outstanding molecular recognition capability of DNA allows it to function as a ‘smart glue' for nanoscale construction. Complementary strands of 20-mer ssDNA were successfully grafted on carboxylated CNXLs using an amide coupling reaction. The ssDNA-CNXL graft was further characterized using FTIR, UV-VIS spectroscopy and dynamic light scattering. CNXLs with complementary DNA single strands were then hybridized in buffer at 350C for 24 hrs to form a DNA-CNXL duplex. Duplexing events were monitored as a function of time and temperature using dynamic light scattering. The materials were then imaged by atomic force microscopy (AFM). |
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Biobased Nanocomposites and Nanotechnology
1:00 PM-5:15 PM, Wednesday, April 9, 2008 Morial Convention Center -- Rm. R09, Oral
Division of Cellulose & Renewable Materials |