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Fetal nucleated red blood cells (fNRBC) in maternal peripheral blood has the potential for non-invasive prenatal diagnostics (NIPD), given its intrinsic nature carrying total genetic information of the fetus. Unfortunately, the scarcity of fNRBCs in maternal blood circulation greatly hinders the effective isolation of fNRBCs and its further uses for clinical prenatal diagnostics. Herein, we developed a gelatin nanoparticles (GNPs) decorated microchip that modified with anti-CD147 as specific capture antibody to efficiently isolate fNRBCs from maternal peripheral blood. The corrugated GNP nanocoating on the walls of the channel, together with herringbone grooves in the continuous curved channel design, produced enhanced interactions between fNRBC and the device for better cell capture performance. Furthermore, the captured cells could be gently released for subsequent off-chip analyses, using an enzymatic treatment to dissolve the biodegradable GNP nanocoating. Significant target cell capture efficiency (>80%), release efficiency (∼89%) and purity (∼85%) as well as a high viability of >90% were achieved using simulated spiked samples. fNRBCs were detected from a series of maternal peripheral blood samples ranging from 7 to 13 weeks of gestation, and the diagnostic application for fetal chromosomal disorders was demonstrated. Our strategy may provide new insights into developing an approach to recover fNRBCs from early pregnancy for improved cell-based NIPD.

Hole transport material free (HTM-free) perovskite solar cells (PSCs) with carbon counter electrode have the advantages of low-cost, good efficiency and high stability. Here in this work, we demonstrate that incorporating Au@SiO2 core-shell NPs into TiO2 scaffold layer increases the power conversion efficiencies (PCEs) of PSCs by improving the light absorption and facilitating carrier transfer or separation through SPR effect. With the optimal concentration of 0.3 wt % Au@SiO2 incorporation, the average PCE of PSCs enhances to 13.85 ± 0.45% from the reference samples of 12.01 ± 0.44%, which is mainly caused by the improved short circuit current density.

Effective capture and release of circulating tumor cells (CTCs) with high viability is still a challenge in medical research. We design a novel approach with efficient yield and high cell activity for the capture and release of CTCs. Our platform is based on TiO2 nanorod arrays coated with transparent MnO2 nanoparticles. We use hydrothermal synthesis to prepare TiO2 nanorod arrays, the MnO2 nanoparticles are fabricated through in situ self-assembly on the substrate to form a monolayer and etched by oxalic acid with low concentration at room temperature. Up to 92.9% of target cells are isolated from the samples using our capture system and the captured cells can be released from the platform, the saturated release efficiency is 89.9%. Employing lower than 2 × 10-3 M concentration of oxalic acid to dissolve MnO2, the viability of MCF-7 cancer cells exceed 90%. Such a combination of the two-dimensional and three-dimensional platforms provides a new approach isolate CTCs from patient blood samples.

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.

Here, we present a platelet-facilitated photothermal tumor therapy (PLT-PTT) strategy, in which PLTs act as carriers for targeted delivery of photothermal agents to tumor tissues and enhance the PTT effect. Gold nanorods (AuNRs) were first loaded into PLTs by electroporation and the resulting AuNR-loaded PLTs (PLT-AuNRs) inherited long blood circulation and cancer targeting characteristics from PLTs and good photothermal property from AuNRs. Using a gene-knockout mouse model, we demonstrate that the administration of PLT-AuNRs and localizing laser irradiation could effectively inhibit the growth of head and neck squamous cell carcinoma (HNSCC). In addition, we found that the PTT treatment augmented PLT-AuNRs targeting to the tumor sites and in turn, improved the PTT effects in a feedback manner, demonstrating the unique self-reinforcing characteristic of PLT-PTT in cancer therapy.

Anatase TiO2 ultra-thin nanosheets (TiO2-NS) are synthesized by a facile hydrothermal method. Several merits are realized when employing the prepared TiO2-NS as lithium ion battery anode material, compared to TiO2 nanoparticles. Firstly, the as-prepared TiO2-NS has high charge capacities and a specific surface area up to 98.8 m2g−1, which is beneficial for the insertion of lithium ion. Secondly, the large specific surface area is helpful in enlarging the electrode/electrolyte interfacial area. Finally, the EIS result verifies short electron transfer paths. More importantly, the stability of the nanosheet structure is indirectly confirmed by the excellent cycling performance of charge capacity and the curve of charge capacities versus cycle number at different current densities. After galvanostatic charge/discharge of the batteries for 1000 cycles, the HRTEM images of post-mortem batteries directly reveal a good reversibility of the lithium ion insertion/extraction process aided by TiO2-NS. Thus, all these advantages and the special structure facilitate an excellent cycling performance: the charge capacity with the maximum value of 250 mAh g−1 keeps half after 2000 cycles at a current density of 840 mA g−1 (5 C).

The recovery of rare single circulating tumor cells (CTCs) from patients has great potential to facilitate the study of cell heterogeneity and cancer metastasis, which may promote the development of individualized cancer immunotherapy. Herein, a versatile single-cell recovery approach that utilizes an acoustic droplet-induced enzyme responsive platform for the capture and on-demand release of single CTCs is proposed. The platform combines a multifunctional enzyme-responsive gelatin nanoparticle (GNP)-decorated substrate (GNP-chip) for specific capture with an acoustic droplet positioning technique to realize on-demand release of single CTCs. The acoustic droplet dispenser is employed to generate oxidized alginate microdroplets containing the MMP-9 enzyme (OA-MMP-9) with controllable size and precise positioning upon the cell-attached GNP-chip, allowing controlled cell-surface biodegradation under enzymatic reactions followed by calcium chloride (CaCl2) solution treatment to form single-cell encapsulated calcium alginate hydrogels. Benefitting from the existence of hydrogels, the released cells could be efficiently recovered by microcapillary. Results demonstrate that the encapsulated cells maintain good cell morphology in the hydrogels, which allow further single-cell nucleic acid analysis. As a proof-of-concept platform, this approach enables reliable and efficient retrieval of single CTCs and holds the potential for versatility in single-cell analysis systems.

Upconversion nanoparticles (UCNPs), with fascinating optical and chemical features, are a promising new generation of fluorescent probes. Although UCNPs have been widely used in diagnosis and therapy, there is an unmet need for a simple and effective surface engineering method that can produce cancer-targeting UCNPs. Here, we show that by coating particles with macrophage membranes, it becomes possible to utilize the adhesion between macrophages and cancer cells for effective cancer targeting. Natural macrophage membranes along with their associated membrane proteins were reconstructed into vesicles and then coated onto synthetic UCNPs. The resulting macrophage membrane-camouflaged particles (MM-UCNPs) exhibited effective cancer targeting capability inherited from the source cells and were further used for enhanced in vivo cancer imaging. Finally, the blood biochemistry, hematology testing and histology analysis results suggested a good in vivo biocompatibility of MM-UCNPs. The combination of synthetic nanoparticles with biomimetic cell membranes embodies a novel design strategy toward developing biocompatible nanoprobes for potential clinical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 521-530, 2017.

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.

In this paper, autofluorescent gelatin nanoparticles were synthesized as matrix metalloproteinase (MMP) responsive probes for cancer cell imaging. A modified two-step desolvation method was employed to generate these nanoparticles whose size was controllable and had stable autofluorescence. As glutaraldehyde was introduced as the crosslinking agent, the generation of Schiff base (CN) and double carbon bond (CC) between glutaraldehyde and gelatin endowed these gelatin nanoparticles distinct autofluorescence. Considering MMPs were usually overexpressed on the surface of cancer cells and they had degradation ability toward gelatin, we utilized these nanoparticles as imaging probes to responsively monitor the MMP metabolism of cancer cells according to the luminance change. As fluorescent probes, these nanoparticles had facile synthesis procedure and good biocompatibility, and provided a smart strategy to monitor cancer cell behaviors. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2854-2860, 2016.

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.

Filtration of circulating tumor cells (CTCs) in peripheral blood is of proven importance for early cancer diagnosis, treatment monitoring, metastasis diagnosis, and prognostic evaluation. However, currently available strategies for enriching CTCs, such as magnetic activated cell sorting (MACS), face serious problems with purity due to nonspecific interactions between beads and leukocytes in the process of capturing. In the present study, the tumor-targeting molecule folic acid (FA) and magnetic nanoparticles (MNPs) were coated on the surface of red blood cells (RBCs) by hydrophobic interaction and chemical conjugation, respectively. The resulting engineered RBCs rapidly adhered to CTCs and the obtained CTC-RBC conjugates were isolated in a magnetic field. After treatment with RBC lysis buffer and centrifugation, CTCs were released and captured. The duration of the entire process was less than three hours. Cell counting showed that the capture efficiency was above 90% and the purity of the obtained CTCs was higher than 75%. The performance of the proposed method exceeded that of MACS® beads (80% for capture efficiency and 20% for purity) under the same conditions. The obtained CTCs could be successfully re-cultured and proliferated in vitro. Our engineered RBCs have provided a novel method for enriching rare cells in the physiological environment.

Recently, red blood cell (RBC) membrane-coated nanoparticles have attracted much attention because of their excellent immune escapability; meanwhile, gold nanocages (AuNs) have been extensively used for cancer therapy due to their photothermal effect and drug delivery capability. The combination of the RBC membrane coating and AuNs may provide an effective approach for targeted cancer therapy. However, few reports have shown the utilization of combining these two technologies. Here, we design erythrocyte membrane-coated gold nanocages for targeted photothermal and chemical cancer therapy. First, anti-EpCam antibodies were used to modify the RBC membranes to target 4T1 cancer cells. Second, the antitumor drug paclitaxel (PTX) was encapsulated into AuNs. Then, the AuNs were coated with the modified RBC membranes. These new nanoparticles were termed EpCam-RPAuNs. We characterized the capability of the EpCam-RPAuNs for selective tumor targeting via exposure to near-infrared irradiation. The experimental results demonstrate that EpCam-RPAuNs can effectively generate hyperthermia and precisely deliver the antitumor drug PTX to targeted cells. We also validated the biocompatibility of the EpCam-RAuNs in vitro. By combining the molecularly modified targeting RBC membrane and AuNs, our approach provides a new way to design biomimetic nanoparticles to enhance the surface functionality of nanoparticles. We believe that EpCam-RPAuNs can be potentially applied for cancer diagnoses and therapies.

Nanotechnology possesses the potential to revolutionize the diagnosis and treatment of tumors. The ideal nanoparticles used for in vivo cancer therapy should have long blood circulation times and active cancer targeting. Additionally, they should be harmless and invisible to the immune system. Here, we developed a biomimetic nanoplatform with the above properties for cancer therapy. Macrophage membranes were reconstructed into vesicles and then coated onto magnetic iron oxide nanoparticles (Fe3O4 NPs). Inherited from the Fe3O4 core and the macrophage membrane shell, the resulting Fe3O4@MM NPs exhibited good biocompatibility, immune evasion, cancer targeting and light-to-heat conversion capabilities. Due to the favorable in vitro and in vivo properties, biomimetic Fe3O4@MM NPs were further used for highly effective photothermal therapy of breast cancer in nude mice. Surface modification of synthetic nanomaterials with biomimetic cell membranes exemplifies a novel strategy for designing an ideal nanoplatform for translational medicine.

Upconversion nanoparticles (UCNPs) with superior optical and chemical features have been broadly employed for in vivo cancer imaging. Generally, UCNPs are surface modified with ligands for cancer active targeting. However, nanoparticles in biological fluids are known to form a long-lived "protein corona", which covers the targeting ligands on nanoparticle surface and dramatically reduces the nanoparticle targeting capabilities. Here, for the first time, we demonstrated that by coating UCNPs with red blood cell (RBC) membranes, the resulting cell membrane-capped nanoparticles (RBC-UCNPs) adsorbed virtually no proteins when exposed to human plasma. We further observed in various scenarios that the cancer targeting ability of folic acid (FA)-functionalized nanoparticles (FA-RBC-UCNPs) was rescued by the cell membrane coating. Next, the FA-RBC-UCNPs were successfully utilized for enhanced in vivo tumor imaging. Finally, blood parameters and histology analysis suggested that no significant systematic toxicity was induced by the injection of biomimetic nanoparticles. Our method provides a new angle on the design of targeted nanoparticles for biomedical applications.

Three-dimensional branched TiO2 architectures (3D BTA) with controllable morphologies were synthesized via a facile template-free one-pot solvothermal route. The volume ratio of deionized water (DI water) and diethylene glycol in solvothermal process is key to the formation of 3D BTA assembled by nanowire-coated TiO2 dendrites, which combines the advantages of 3D hierarchical structure and 1D nanoscale building blocks. Benefiting from such unique structural features, the BTA in full bloom achieved significantly increased specific surface areas and shortened Li(+) ion/electrons diffusion pathway. The lithium-ion batteries based on BTA in full bloom exhibited remarkably enhanced reversible specific capacity and rate performance, attributing to the high contact area with the electrolyte and the short solid state diffusion pathway for Li(+) ion/electrons promoting lithium insertion and extraction.

Biomimetic cell-membrane-camouflaged particles with desirable features have been widely used for various biomedical applications. However, there are few reports on employing these particles for cancer drug delivery due to the failure of the membrane coatings to be efficiently degraded in the tumor microenvironment which hampers the drug release. In this work, core-shell SiO2 @TiO2 nanoparticles with enhanced photocatalytic activity are used for controlled degradation of surface erythrocyte membrane coatings. The antitumor drug docetaxel is encapsulated into nanocarriers to demonstrate the controlled drug release under ultraviolet irradiation, and the drug-loaded nanoparticles are further used for enhanced cancer cell therapy. Here, a simple but practical method for degradation of cell membrane coatings is presented, and a good feasibility of using cell membrane-coated nanocarriers for controlled drug delivery is demonstrated.

In this work, we developed a shape-controllable nozzle inside a multilayer PDMS microchip. The nozzle was able to control the shape of the fluid channel in three dimensions. All the four walls of the fluid channel were comprised of pneumatic PDMS membrane valves, and their deformation was controlled by air pressure. As both the limitation of the fluid flux and the shape of the fluid channel were adjustable spatially in three dimensions, this valve-based nozzle generated droplets with less response time and in a more effectively controlled manner comparing to conventional droplet devices. It could also function as a microinjector to modulate the compositions of droplets precisely and continuously. In addition, the nozzle was able to form a specific shape to generate core–shell particles.

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.

Cancer cell membrane-coated upconversion nanoprobes (CC-UCNPs) with immune escape and homologous targeting capabilities are used for highly specific tumor imaging. The combination of UCNPs with biomimetic cancer cell membranes embodies a novel materials design strategy and presents a compelling class of advanced materials.

Microfluidics-based circulating tumor cell (CTC) isolation is achieved by using gelatin-coated silica microbeads conjugated to CTC-specific antibodies. Bead-binding selectively enlarges target cell size, providing efficient high-purity capture. CTCs captured can be further released non-invasively. This stratagem enables high-performance CTC isolation for subsequent studies.

Non-invasive prenatal diagnostics (NIPD) has been an emerging field for prenatal diagnosis research. Carrying the whole genome coding of the fetus, fetal nucleated red blood cells (FNRBCs) have been pursued as a surrogate biomarker traveling around in maternal blood. Here, by combining a unique microbead-based centrifugal separation and enzymatic release, we demonstrated a novel method for FNRBC isolation from the blood samples. First, the gelatin-coated silica microbeads were modified with FNRBC-specific antibody (anti-CD147) to capture the target cells in the blood samples. Then, the density difference between microbead-bound FNRBCs and normal blood cells enables the purification of FNRBCs via an improved high-density percoll-based separation. The non-invasive release of FNRBCs can then be achieved by enzymatically degrading the gelatin film on the surface of the microbeads, allowing a gentle release of the captured target cells with as high as 84% efficiency and ∼80% purity. We further applied it to isolate fetal cells from maternal peripheral blood. The released cells were analyzed by real-time polymerase chain reaction to verify their fetal origin and fluorescent in situ hybridization to detect fetal chromosome disorders. This straightforward and reliable alternative platform for FNRBC detection may have the potential for realizing facile NIPD.

A piezoelectric nanogenerator based on poly(vinylidene fluoride trifluoroethylene) [P(VDF-TrFE)] nanofibers with an Au interdigital electrode (IDT)/P(VDF-TrFE) nanofiber film/well-ordered cylindrical cavity structure was prepared by combining Au IDTs with a rotary collector to obtain highly aligned P(VDF-TrFE) nanofiber arrays. The Au IDTs work not only as parallel electrodes to collect P(VDF-TrFE) nanofibers during electrospinning but also as charge-collecting electrodes in the nanogenerator. The well-ordered cylindrical cavities improve output performance by enhancing the deformation of P(VDF-TrFE) nanofiber films when subjected to external force. The nanogenerator performs well; as an example of application, we demonstrate energy harvesting from human walking, with a peak output voltage of 5 V and a peak short-circuit current of 1.2 μA. Such a device could have practical applications in wearable, self-powered devices.

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).

Nanoparticles possess the potential to revolutionize cancer diagnosis and therapy. The ideal theranostic nanoplatform should own long system circulation and active cancer targeting. Additionally, it should be nontoxic and invisible to the immune system. Here, the authors fabricate an all-in-one nanoplatform possessed with these properties for personalized cancer theranostics. Platelet-derived vesicles (PLT-vesicles) along with their membrane proteins are collected from mice blood and then coated onto Fe3O4 magnetic nanoparticles (MNs). The resulting core–shell PLT-MNs, which inherit the long circulation and cancer targeting capabilities from the PLT membrane shell and the magnetic and optical absorption properties from the MN core, are finally injected back into the donor mice for enhanced tumor magnetic resonance imaging (MRI) and photothermal therapy (PTT). Meanwhile, it is found that the PTT treatment impels PLT-MNs targeting to the PTT sites (i.e., tumor sites), and exactly, in turn, the enhanced targeting of PLT-MNs to tumor sites can improve the PTT effects. In addition, since the PLT membrane coating is obtained from the mice and finally injected into the same mice, PLT-MNs exhibit stellar immune compatibility. The work presented here provides a new angle on the design of biomimetic nanoparticles for personalized diagnosis and therapy of various diseases.

The influence of electron dosage on the field induced strain, dielectric constant, and polarization response has been investigated in electron irradiated poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) 50/50 copolymer. It was found that under suitable electron dosage an ultrahigh electrostrictive strain can be achieved. Interestingly, material after irradiation exhibits many features resembling those of relaxor ferroelectrics, suggesting that the electron irradiation breaks up the coherent polarization domain in normal ferroelectric P(VDF-TrFE) copolymer into nano-polar regions that transform the material into a relaxor ferroelectric. In addition, many of the material properties including the field induced polarization, the electrostrictive strain, and elastic modulus exhibit irregular change (non-monotonical) with electron dosage, indicating a complex relation among the crosslinking density, crystallinity, crystallite size, and molecular conformation in determining the material responses.

Aiming to synthesize multiferroic materials in microscale, a microfluidic device capable of generating multiferroic Janus microparticles is demonstrated. Through bonding two polydimethylsiloxane (PDMS) layers “face to face,” laminar flow containing an upper layer and a lower layer can be realized. Accordingly, poly(vinylidene fluoride-trifluoroethylene) ferroelectric polymers and Fe3O4 ferromagnetic particles are separately encapsulated in the two layers of a single droplet. Numerical simulation enables the analysis of cross-mixing between the two counterparts and helps to find an optimized location for adding subsequent ultraviolet treatment, which will polymerize the droplets into Janus particles without any side effect. By modulation of the flow rate, the size of the Janus particles can be precisely tuned. Finally, the ferroelectricity and magnetism of the Janus particles are verified by the magnetization and polarization measurements, indicating the multiferroic nature.

Suppression of the reticuloendothelial system (RES) uptake is one of the most challenging tasks in nanomedicine. Coating stratagems using polymers, such as poly(ethylene glycol) (PEG), have led to great success in this respect. Nevertheless, recent observations of immunological response toward these synthetic polymers have triggered a search for better alternatives. In this work, natural red blood cell (RBC) membranes are camouflaged on the surface of Fe3O4 nanoparticles for reducing the RES uptake. In vitro macrophage uptake, in vivo biodistribution and pharmacokinetic studies demonstrate that the RBC membrane is a superior alternative to the current gold standard PEG for nanoparticle 'stealth'. Furthermore, we systematically investigate the in vivo potential toxicity of RBC membrane-coated nanoparticles by blood biochemistry, whole blood panel examination and histology analysis based on animal models. The combination of synthetic nanoparticles and natural cell membranes embodies a novel and biomimetic nanomaterial design strategy and presents a compelling property of functional materials for a broad range of biomedical applications.