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Abstract Background Circulating tumor cells (CTCs) comprise the high metastatic potential population of cancer cells in the blood circulation of humans; they have become the established biomarkers for cancer diagnosis, individualized cancer therapy, and cancer development. Technologies for the isolation and recovery of CTCs can be powerful cancer diagnostic tools for liquid biopsies, allowing the identification of malignancies and guiding cancer treatments for precision medicine. Methods We have used an electrospinning process to prepare poly(lactic-co-glycolic acid) (PLGA) nanofibrous arrays in random or aligned orientations on glass slips. We then fabricated poly(methyl methacrylate) (PMMA)-based microfluidic chips embedding the PLGA nanofiber arrays and modified their surfaces through sequential coating with using biotin–(PEG)7–amine through EDC/NHS activation, streptavidin (SA), and biotinylated epithelial-cell adhesion-molecule antibody (biotin-anti-EpCAM) to achieve highly efficient CTC capture. When combined with an air foam technology that induced a high shear stress and, thereby, nondestructive release of the captured cells from the PLGA surfaces, the proposed device system operated with a high cell recovery rate. Results The morphologies and average diameters of the electrospun PLGA nanofibers were characterized using scanning electron microscopy (SEM) and confocal Raman imaging. The surface chemistry of the PLGA nanofibers conjugated with the biotin–(PEG)7–amine was confirmed through time-of-flight secondary ion mass spectrometry (ToF–SIMS) imaging. The chip system was studied for the effects of the surface modification density of biotin–(PEG)7–amine, the flow rates, and the diameters of the PLGA nanofibers on the capture efficiency of EpCAM-positive HCT116 cells from the spiked liquid samples. To assess their CTC capture efficiencies in whole blood samples, the aligned and random PLGA nanofiber arrays were tested for their abilities to capture HCT116 cells, providing cancer cell capture efficiencies of 66 and 80%, respectively. With the continuous injection of air foam into the microfluidic devices, the cell release efficiency on the aligned PLGA fibers was 74% (recovery rate: 49%), while it was 90% (recovery rate: 73%) on the random PLGA fibers, from tests of 200 spiked cells in 2 mL of whole blood from healthy individuals. Our study suggests that integrated PMMA microfluidic chips embedding random PLGA nanofiber arrays may be suitable devices for the efficient capture and recovery of CTCs from whole blood samples.

The oriented 1D nanostructure arrays of PANI have great potential applications in various devices. In this paper, we report a simple and facile one-step template-free way to assemble highly oriented arrays of PANI nanofibers using chemical oxidative polymerization on the glass and polymer flexible substrates. The diameters of the individual nanofibers range from 10 nm to 33 nm, and the average length of the aligned nanofibers is up to 48–139 nm. The PANI nanofiber arrays can be uniformly distributed on the whole substrates via this method, which are confirmed by the results of SEM images and Raman mapping. The as-prepared PANI nanofiber arrays can be potentially used in flexible low-voltage electronics, anti coatings, self-cleaning surfaces and chemical sensors, and so on. [ABSTRACT FROM AUTHOR]

MnO x S 2−x nanofiber arrays is successfully prepared by one-step electrochemical deposition at 343 K on Ti substrates. The as-prepared MnO x S 2−x fibers are amorphous structure, which is confirmed by X-ray diffraction (XRD) results, and the stoichiometry is checked by X-ray photoelectron spectroscopy (XPS). The highest specific capacitance (Cs) of 278.22 F/g is obtained by cyclic voltammogram (CV) in a scan rate of 1 mV/s, and 214.78 F/g by galvanostatic charge discharge (GCD) technique at 1 mA/cm 2 current rate, which is higher than that of pure MnO 2 . [ABSTRACT FROM AUTHOR]

Nanoscaled photonic devices rely on a thorough understanding of the influence of microscopic morphological changes on the optoelectronic properties. Here, we investigate as a model system, organic nanofibers and microrings from para-phenylene molecules, which provide high flexibility in terms of controlled growth manipulation, while, on the other hand, showing self-assembled multiplication of individual entities. Examples on selective spectroscopy, scanning fluorescence optical microscopy, and waveguiding of individual nanofibers, as well as arrays of nanofibers are given. Both the linear optical properties, as well as the waveguiding efficiency are strongly related to the morphology of the nanoaggregates. Organic nanoaggregates, thus, are an interesting benchmark system for the investigation of the applicability of a variety of optical methods in the nanodomain. [ABSTRACT FROM PUBLISHER]

This is a report on optical switching patterns textured by electrospun nanofibers according to the direction of the incident light. The effect of fiber size is also explained. Depending on the direction of the incident light, there should be two distinct reflective behaviors on the surfaces of the nanofibers: diffuse and specular reflections. The mechanism for this critical phenomenon is explained in terms of the cylindrical geometry of the fiber surface, and the 'on-off' reflective behavior can be maximized when the diameters of the fibers are quite small, such as nanofibers. [ABSTRACT FROM AUTHOR]

Superwettable solid surfaces have attracted substantial research interest due to their outstanding performance. Various approaches have been developed for preparing superwettable surfaces via constructing a highly textured surface roughness and/or altering the surface free energy. Here, a facile dewetting strategy is proposed to produce multiple superwettabilities on copper hydroxide nanofiber arrays (Cu(OH)2‐NFAs) by controlling the localized state of low‐energy silicone oil. It is proposed that both the capillary forces along each nanofiber and the evaporation of the octane solvent contribute to the localization of the silicone oil in the NFAs. By varying the concentration of the silicone oil, its localized state changes from a scattered discontinuous distribution to a continuous thin/thick film, which leads to variations in the surface energy and surface roughness. Consequently, Cu(OH)2‐NFAs with superhydrophilicity, superhydrophobicity with both high and low adhesion, and super slippery properties are prepared. Notably, a very small amount of silicone oil can alter the surface wettability of the Cu(OH)2‐NFAs from superhydrophilic to superhydrophobic, which is attributable to the migration of silicone oil to the top of the nanofibers during the dewetting process. These results will provide new insights on the facile fabrication of functional surfaces with multiple superwettabilities. [ABSTRACT FROM AUTHOR]

Background: Circulating tumor cells (CTCs) comprise the high metastatic potential population of cancer cells in the blood circulation of humans; they have become the established biomarkers for cancer diagnosis, individualized cancer therapy, and cancer development. Technologies for the isolation and recovery of CTCs can be powerful cancer diagnostic tools for liquid biopsies, allowing the identification of malignancies and guiding cancer treatments for precision medicine. Methods: We have used an electrospinning process to prepare poly(lactic-co-glycolic acid) (PLGA) nanofibrous arrays in random or aligned orientations on glass slips. We then fabricated poly(methyl methacrylate) (PMMA)-based microfluidic chips embedding the PLGA nanofiber arrays and modified their surfaces through sequential coating with using biotin–(PEG)7–amine through EDC/NHS activation, streptavidin (SA), and biotinylated epithelial-cell adhesion-molecule antibody (biotin-anti-EpCAM) to achieve highly efficient CTC capture. When combined with an air foam technology that induced a high shear stress and, thereby, nondestructive release of the captured cells from the PLGA surfaces, the proposed device system operated with a high cell recovery rate. Results: The morphologies and average diameters of the electrospun PLGA nanofibers were characterized using scanning electron microscopy (SEM) and confocal Raman imaging. The surface chemistry of the PLGA nanofibers conjugated with the biotin–(PEG)7–amine was confirmed through time-of-flight secondary ion mass spectrometry (ToF–SIMS) imaging. The chip system was studied for the effects of the surface modification density of biotin–(PEG)7–amine, the flow rates, and the diameters of the PLGA nanofibers on the capture efficiency of EpCAM-positive HCT116 cells from the spiked liquid samples. To assess their CTC capture efficiencies in whole blood samples, the aligned and random PLGA nanofiber arrays were tested for their abilities to capture HCT116 cells, providing cancer cell capture efficiencies of 66 and 80%, respectively. With the continuous injection of air foam into the microfluidic devices, the cell release efficiency on the aligned PLGA fibers was 74% (recovery rate: 49%), while it was 90% (recovery rate: 73%) on the random PLGA fibers, from tests of 200 spiked cells in 2 mL of whole blood from healthy individuals. Our study suggests that integrated PMMA microfluidic chips embedding random PLGA nanofiber arrays may be suitable devices for the efficient capture and recovery of CTCs from whole blood samples. [ABSTRACT FROM AUTHOR]