Endothelialization of TiO2 Nanorods Coated with Ultrathin Amorphous Carbon Films

The influence of physical and spatial substrate characteristics on endothelial cells

Cardiovascular diseases are a main cause of death worldwide, leading to a growing demand for medical devices to treat this patient group. Central to the engineering of such devices is a good understanding of the biology and physics of cell-surface interactions. In existing blood-contacting devices, such as vascular grafts, the interaction between blood, cells, and material is one of the main limiting factors for their long-term durability. An improved understanding of the material's chemical- and physical properties as well as its structure all play a role in how endothelial cells interact with the material surface. This review provides an overview of how different surface structures influence endothelial cell responses and what is currently known about the underlying mechanisms that guide this behavior. The structures reviewed include decellularized matrices, electrospun fibers, pillars, pits, and grated surfaces.

A highly sensitive TiO2-based molecularly imprinted photoelectrochemical sensor with regulation of imprinted sites by Photo-deposition

Molecularly imprinted photoelectrochemical sensors (MIPES) have gained significant attention in the detection field due to their high selectivity and accuracy. However, their sensitivity still needs improvement. Here we developed a TiO2-based MIPES (TiO2 NRs/NiOOH/rMIP) to detect ciprofloxacin (CIP). We identified the photoactive sites of TiO2 by NiOOH photo-deposition and anchored the imprinted sites on the photoactive sites by complexation between CIP and NiOOH. By regulating the imprinted sites, the photocurrent difference before and after the addition of CIP increases and the detection sensitivity of CIP is improved. Moreover, a PN heterojunction is formed between TiO2 and NiOOH, which enables rapid transfer of photoexcited holes and electrons to different semiconductors under the built-in electric field. This leads to improved photoactivity of TiO2 and further increases the sensitivity of MIPES. Compared with sensors prepared by the traditional electro-polymerization CIP and Molecularly imprinted polymers (TiO2 NRs/NiOOH/eMIP), TiO2 NRs/NiOOH/rMIP as constructed in this work displays higher sensitivity, wider linear detection range, and lower limit of detection (LOD). Additionally, TiO2 NRs/NiOOH/rMIP shows good selectivity, stability, and recovery rate, and has a promising application prospect in the actual detection of antibiotics.

Enhancing interactions between cells and hierarchical micro/nanostructured TiO2films for efficient capture of circulating tumor cells

Micro/nano hierarchical substrates with different micropillar spacings were designed and prepared for capture of tumor cells. The cell capture efficiency of hierarchical substrates with low-density micropillar arrays was similar to that of nanostructured substrate. Increasing the density of micopillars could significantly improve the capture efficiency. The maximum capture efficiency was achieved on the hierarchical substrate with micropillar spacings of 15μm, but further reducing the micropillar spacings did not increase the cell capture efficiency. It was also found that hierarchical substrates with appropriate spacing of micropillars appeared more favorable for cell attachment and spreading, and thus enhancing the cell-material interaction. These results suggested that optimizing the micropillar arrays, such as the spacing between adjacent micropillars, could give full play to the synergistic effect of hierarchical hybrid micro/nanostructures in the interaction with cells. This study may provide promising guidance to design and optimize micro/nano hierarchical structures of biointerfaces for biomedical application.