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The isolation and analysis of scarce circulating tumor cells (CTCs) with immunomagnetic nanoparticles (IMNs) have shown promising outcomes in noninvasive cancer diagnosis. However, the IMNs adsorb nonspecific proteins after entering into biofluids and the formed protein coronas cover surface targeting ligands, limiting the detection efficiency of IMNs. In addition, the interaction between surface targeting ligands and white blood cells (WBCs) significantly limits the purity of CTCs isolated by IMNs. Furthermore, the interfacial collision of nanoparticles and cells has negative effects on the viability of isolated CTCs. All of these limitations synthetically restrict the isolation and analysis of rare CTCs for early diagnosis and precision medicine. Here, we proposed that surface functionalization of IMNs with neutrophil membranes can simultaneously reduce nonspecific protein adsorption, enhance the interaction with CTCs, reduce the distraction from WBCs, and improve the viability of isolated CTCs. In spiked blood samples, our neutrophil membrane-coated IMNs (Neu-IMNs) exhibited a superior separation efficiency from 41.36% to 96.82% and an improved purity from 40.25% to 90.68% when compared to bare IMNs. Additionally, we successfully isolated CTCs in 19 out of total 20 blood samples from breast cancer patients using Neu-IMNs and further confirmed the feasibility of the isolated CTCs for downstream cell sequencing. Our work provides a new perspective on engineered IMNs for efficient isolation and analysis of CTCs, paving the way for early noninvasive diagnosis of cancer.

Background: Circulating tumor cells (CTCs) are a burgeoning topic in cancer biomarker discovery research with minimal invasive blood draws. CTCs can be used as potential biomarkers for disease prognosis, early cancer diagnosis and pharmacodynamics. However, the extremely low abundance of CTCs limits their clinical utility because of technical challenges such as the isolation and subsequent detailed molecular and functional characterization of rare CTCs from patient blood samples. Methods: In this study, we present a novel density gradient centrifugation method employing biodegradable gelatin nanoparticles coated on silicon beads for the isolation, release, and downstream analysis of CTCs from colorectal and breast cancer patients. Results: Using clinical patient/spiked samples, we demonstrate that this method has significant CTC-capture efficiency (>80%) and purity (>85%), high CTC release efficiency (94%) and viability (92.5%). We also demonstrate the unparalleled robustness of our method in downstream CTC analyses such as the detection of PIK3CA mutations. Conclusion: The efficiency and versatility of the multifunctional density microbeads approach provides new opportunities for personalized cancer diagnostics and treatments.

The two-step spin coating process produces rough perovskite surfaces in ambient condition with high humidity, which are unfavorable for the contact between the perovskite film and the low temperature carbon electrode. To tackle this problem, multi-walled carbon nanotubes (MWCNTs) are embedded into the perovskite layer. The MWCNTs can act as charge transport high way between individual perovskite nanoparticles and facilitate the collection of the photo-generated holes by the carbon electrode. Longer carrier lifetime is confirmed in the perovskite solar cells with addition of MWCNTs using open circuit voltage decay measurement. Under optimized concentration of MWCNT, average power conversion efficiency of 11.6% is obtained in hole transport material free perovskite solar cells, which is boosted by ∼15% compared to solar cells without MWCNT.

A mesoporous SiO2 layer is successfully introduced into the hole transport material free perovskite solar cells by spin-coating a SiO2 paste onto the TiO2 scaffold layer. This SiO2 layer can act as an insulating layer and effectively inhibit the charge recombination between the TiO2 layer and carbon electrode. The variation of power conversion efficiencies with the thickness of SiO2 layer is studied here. Under optimized SiO2 thickness, perovskite solar cell fabricated on the TiO2/SiO2 film shows a superior power conversion efficiency of ∼12% and exhibits excellent long time stability for 30 days.

An optimized two-step sequential deposition method to fabricate hole-transport-layer-free carbon-based methyl ammonium lead bromide (MAPbBr3) perovskite solar cells is reported. Small amounts of MABr are introduced into the PbBr2 precursor solution during the first step to prepare MAPbBr3 perovskite films (labeled as MAPB-xMABr), which promotes the conversion of PbBr2 into perovskite phase and results in denser perovskite films with increased crystallinity, lower trap density, and longer carrier lifetime. After optimization, a maximum power conversion efficiency (PCE) of 7.64% (VOC = 1.36 V) is obtained for MAPB-0.2MABr based solar cells. Significantly, the non-encapsulated devices exhibit excellent long-term stability in ambient air (25–30 °C and 20–30% relative humidity), showing no degradation after a year’s exposure. While, it also shows superior thermal stability with PCE retaining 95% of the initial efficiency after 120 h under thermal stress of 80 °C and 40–70% relative humidity.

Two dimensional materials have promising benefits in photoelectronic devices, including facilitating charge transport and reducing defects in perovskite solar cells (PSCs) and photodetectors (PDs) through interface engineering. Herein, a two dimension polymeric material of graphitic carbon nitride quantum dots (g-CNQDs) interlayer is used to modify the SnO2/perovskite interface in both ambient PSCs and PDs to improve the overall performance. The introduction of g-CNQD layer improves the crystalline quality of sequential perovskite absorber with high phase purity, less grain boundaries, low trap states and suppressed carrier recombination due to the intrinsic cross-linkable feature and relatively smooth surface of g-CNQD. As a result, with optimal modification, fully air-processed PSC reached a champion power conversion efficiency of 21.23% with negligible hysteresis, and the PDs had remarkable performance enhancement. Moreover, our PSCs have good stability in ambient air, keeping over 90% of the initial efficiency after 30 days’ exposure.

Stable hosts containing pre-stored metallic lithium (Li) are typically used to tackle irregular dendrite formation and infinite relative volume changes of lithium metal anodes. In this sense, oversimplified molten Li infusion strategies have been widely proposed to build lithiophilic architectures with uncontrollable amount and configuration of metallic Li in obtained hosts. In this work, tin oxide (SnO2) deposited Ni foam (SNF) with superior molten Li wettability is employed to construct two distinct lithiophilic architectures namely, Li coated SNF skeletons and Li infiltrated SNF frameworks. The cycling stability and dendritic behavior of these lithiophilic architectures are systematically compared. Both of these lithiophilic architectures significantly outperformed bare Li foils in terms of cycling performance and electrode dimension stability. The fully covered lithiophilic host with Li infiltrated SNF frameworks shows much better cycling stability and lower hysteresis than the porous lithiophilic host with Li coated skeletons, especially at high current densities and large stripping/plating capacities. In full-cell configurations, the batteries based on Li infiltrated SNF frameworks also show significantly higher rate capabilities than Li coated SNF skeletons counterpart. Our results provide a better understanding to design stable lithiophilic hosts for high-rate and high-capacity lithium metal anodes.

Liquid electrolytes employing fluorescent perylene are prepared and applied in dye sensitized solar cells (DSSCs). Due to the excellent down-shifting property of perylene, photons with short wavelength (from about 350 to 440 nm) can be absorbed and then converted to ones with longer wavelength (from 450 nm to 550 nm) which can be more efficiently utilized by DSSCs. As a result, device with optimal concentration of 0.05 M perylene presents an efficient improvement in the short-circuit current density ( J sc ), leading to an increase of 11.6% in the power conversion efficiency (PCE) compared with the reference DSSC based on control electrolyte.

We report on the feasible fabrication of microfluidic devices for ferroelectric polymers' synthesis in a rapid and stable fashion. Utilizing micro-mixing and flow-focusing in microchannels, poly(vinylidene fluoride-trifluoroethylene) and copper phthalocyanine are uniformly dispersed in one hydrogel particle, which are then demonstrated to immediate and complete on-chip steady polymerization by moderate ultraviolet treatment. The advantage of our droplet-based microfluidic devices is generating versatile particles from simple spheres to disks or rods, and the lengths of particles can be precisely tuned from 30 to 400 μm through adjusting the flow rates of both disperse and oil phases. In addition, this mixed technique allows for the continuous production of dielectric microparticles with controlled dielectric properties between 10 and 160. Such a microfluidic device offers a flexible platform for multiferroic applications.

This work was financially supported by the National Natural Science Foundation of China (No. 21671096), the Shenzhen Key Laboratory Project (No. ZDSYS201603311013489), the Natural Science Foundation of Shenzhen (Nos. JCYJ20170412153139454, JCYJ20150630145302231, JCYJ20150331101823677), and the Fundamental Research Funds for the Central Universities (No. JZ2016HGTB0725).

Exploring solar energy in the infrared range over 800nm is one of possible way to substantially increasing the photo to electrical transfer efficiancy over the 32% limit. Intermediate bands introduced by N and/or P type dopants may pave the way to utilizing the low energy solar photons. Experimental results are reported to demostrate the trace-amount W-doping might significantlly changed the band structure of TiO2 nanoparticals and enhansed the performance of DSCs and even PSCs.

Hydrogen-induced degradation in CaCu 3 Ti 4 O 12 (CCTO) ceramics was studied using an electrochemical hydrogen charging method, in which the silver electrodes of CCTO ceramic pellets were made a cathode in 0.01 M NaOH solution to deposit hydrogen through the electrolysis of water. The dielectric loss was greatly increased and the insulation resistance was greatly decreased after the treatment. X-ray diffraction analysis showed that no new phases were formed. It is proposed that atomic hydrogen is diffused into CCTO lattice and free electrons are formed through the ionization of hydrogen atoms, which lead to the observed degradation. Hydrogen-induced degradation occurs very quickly in CCTO ceramics and it is important to prevent hydrogen-induced degradation in CCTO ceramics.

Methods for tagging biomolecules with fluorine 18 as immuno-positron emission tomography (immunoPET) tracers require tedious optimization of radiolabeling conditions and can consume large amounts of scarce biomolecules. We describe an improved method using a digital microfluidic droplet generation (DMDG) chip, which provides computer-controlled metering and mixing of 18F tag, biomolecule, and buffer in defined ratios, allowing rapid scouting of reaction conditions in nanoliter volumes. The identified optimized conditions were then translated to bench-scale 18F labeling of a cancer-specific engineered antibody fragments, enabling microPET imaging of tumors in xenografted mice at 0.5 to 4 hours postinjection.

We present a microfluidic system with integrated surface modified piezoelectric sensor for trapping and label-free detection of target samples that can be used for cancer diagnosis. To introduce active magnetic force control to the piezoelectric sensor and obtain a fast regenerative system, a nickel pillar array was patterned onto the surface of quartz crystal microbalance. The functionalities of the system were tested by trapping suspended superparamagnetic micro-beads (SPMBs) in fluids onto the nickel pillar array with a manually controlled magnetic field and by detecting the accumulated mass from the resonant characterization of the piezoelectric sensor at the same time. The results showed the efficiency of the system in manipulating the SPMBs and the sensitivity of the device was of 5 Hz mm2/ng. With surface-functionalized SPMBs, the microfluidic system succeeded in trapping and detecting target cancer cells. A549 cancer cells were captured on the nickel pillar array with WGA protein-functionalized SPMBs and detected with a total mass of 90.6 ng. With its simplicity, low production cost and high efficiency, this new device configuration would be useful for the future point-of-care clinical applications.

The first report of synthetic diamond involved a high-pressure high-temperature (HPHT) process in which diamond was the thermodynamically stable phase1. Subsequent attempts to make diamond at less extreme conditions culminated in the rapid growth of diamond films by chemical vapour deposition2,3. But the question of whether diamond might be grown in hydrothermal conditions mimicking those under which it is formed in the Earth has been long debated4–6. It seems reasonable to suppose that metals might play a catalytic or solubilizing role in this context, given their role in the HPHT method1, in a recent low-pressure solid-state synthetic approach7 and in the recrystallization of diamond in the Ni–NaOH–C system8. Hydrothermal synthesis of diamond has been explored at some length9–13, but with equivocal results. Here we report evidence from spectro-scopic, diffraction and microscopic techniques which suggest that aggregates, tens of micrometres in size, of small diamond crystals can be grown in a hydrothermal environment from a mixture of carbon, water and metal (usually pure nickel). Crucially, we have been able to distinguish new diamond from the diamond seeds added to nucleate new growth.

In this paper, a gradient mesoporous carbon (GMC) monolith derived from the mixtures of phenolic resin (PF) and ethylene glycol (EG) was prepared by a facile route based on polymerization-induced phase separation under temperature gradient (TG). A graded biphasic structure of PF-rich and EG-rich phases was first formed in preform under a TG, and then the preform was pyrolyzed to obtain the GMC monolith. The TG is mainly induced by the thermal resistance of the preferential phase separation layer at high temperature region. The pore structure of the monolith changes gradually along the TG direction. When the TG varies from 58°C to 29°C, the pore size, apparent porosity and specific surface area of the monolith range respectively from 18 nm to 83 nm, from 32% to 39% and from 140.5 m2/g to 515.3 m2/g. The gradient porous structure of the monolith is inherited from that of the preform, which depends on phase separation under TG in the resin mixtures. The pyrolysis mainly brings about the contraction of the pore size and wall thickness as well as the transformation of polymerized PF into glassy carbon.

Methods for tagging biomolecules with fluorine 18 as immuno-positron emission tomography (immunoPET) tracers require tedious optimization of radiolabeling conditions and can consume large amounts of scarce biomolecules. We describe an improved method using a digital microfluidic droplet generation (DMDG) chip, which provides computer-controlled metering and mixing of 18F tag, biomolecule, and buffer in defined ratios, allowing rapid scouting of reaction conditions in nanoliter volumes. The identified optimized conditions were then translated to bench-scale 18F labeling of a cancer-specific engineered antibody fragments, enabling microPET imaging of tumors in xenografted mice at 0.5 to 4 hours postinjection.