Chitosan is a useful and versatile biopolymer with several industrial and biological applications. Whereas its physical and physicochemical bulk properties have been explored quite intensively in the past, there is a lack of studies regarding the morphology and growth mechanisms of thin films of this biopolymer. Of particular interest for applications in bionanotechnology are ultrathin films with thicknesses under 500 Å. Here, we present a study of thin chitosan films prepared in a dry process using physical vapor deposition and in situ ellipsometric monitoring. The prepared films were analyzed with atomic force microscopy in order to correlate surface morphology with evaporation parameters. We find that the surface morphology of our final thin films depends on both the optical thickness, i.e., measured with ellipsometry, and the deposition rate. Our work shows that ultrathin biopolymer films can undergo dewetting during film formation, even in the absence of solvents and thermal annealing.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acs.biomac.5b01750 | DOI Listing |
ChemSusChem
December 2024
TCG-CREST, Research Institute for Sustainable Energy (RISE), INDIA.
Hydrogen evolution reaction (HER) is a key reaction in electrochemical water splitting for hydrogen production leading to the development of potentially sustainable energy technology. Importantly, the catalysts required for HER must be earth-abundant for their large-scale deployment; silicates representing one such class. Herein, we have synthesized a series of transition mono- and bi- metal metasilicates (with SO32- group) using facile wet-chemical method followed by calcination at a higher temperature.
View Article and Find Full Text PDFChemistry
December 2024
Tohoku University - Katahira Campus: Tohoku Daigaku, Advanced Institute for Materials Research, Advanced Institute for Materials Research, 980-8577, Sendai, JAPAN.
A series of CoFe2O4 materials derived from metal-organic framework were successfully constructed by the solvent-thermal method. The morphology of a typical sample CoFe2O4-1 was mostly in the form of a cubic rod-like structure with a size distribution of 3.2 ± 0.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
Tianjin University, Materials Science and Engineering, CHINA.
Multispectral camouflage materials play a vital role in sophisticated multi-band electromagnetic (EM) applications. However, conventional single-band stealth is difficult to align with the growing demand for multi-band compatibility and intelligent adaptation. Herein, we report the design and synthesis of cephalopod-inspired MXene-integrated cholesteric liquid crystal elastomers (MXene-CLCEs) with multispectral camouflage capability, which was fabricated through in situ thiol-acrylate Michael addition and free-radical photopolymerization of CLCE precursor and isocyanate-mediated robust covalent chemical bonding of MXene nanocoating at the interface.
View Article and Find Full Text PDFAge Ageing
November 2024
Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People's Republic of China.
Background: Immunity and inflammation may be essential to the pathogenesis of dementia. However, the association of immune-mediated diseases with the risk of incident dementia has not been well characterised.
Objectives: We aimed to investigate the prospective association of 27 immune-mediated diseases and incident dementia risk and to explore the underlying mechanisms driven by brain structures.
Nanoscale
December 2024
Department of Pharmaceutics, H. R. Patel Institute of Pharmaceutical Education & Research, Shirpur-425405, Maharashtra, India.
The main issues with current and traditional cancer therapy delivery systems include a lack of selectivity towards tumors, causing harm to healthy cells, low efficiency in loading drugs, and the inability to visually track the drug's localization after administration. These limitations negatively impact the effectiveness of therapy and result in increased treatment costs. Furthermore, conventional cancer therapies typically target tumor cells through a single mechanism, which eventually leads to the emergence of drug resistance.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!