Building Robust Carbon Nanotube-Interweaved-Nanocrystal Architecture for High-Performance Anode Materials

Rational design of electrode materials is essential but still a challenge for lithium-ion batteries. Herein, we report the design and fabrication of a class of nanocomposite architecture featured by hierarchically structured composite particles that are built from iron oxide nanocrystals and carbon nanotubes. An aerosol spray drying process was used to synthesize this architecture. Such nanoarchitecture enhanced the ion transport and conductivity that are required for high-power anodes. The large volume changes of the anodes during lithium insertion and extraction are accommodated by the particle’s resilience and internal porosity. High reversible capacities, excellent rate capability, and stable performance are attained. The synthesis process is simple and broadly applicable, providing a general approach toward high-performance energy storage materials

Encapsulating Therapeutic Proteins with Polyzwitterions for Lower Macrophage Nonspecific Uptake and Longer Circulation Time

Numerous efforts have been made to promote the efficiency of protein delivery through tuning the protein surface properties such as grafting polymers on protein surface, but limited successes have been achieved, and their great clinical expectation has not yet been realized. The main reason is that proteins are readily recognized as foreign materials under physiological conditions due to the genetic distance between species, leading to rapid decrease in activity and clearance by mononuclear phagocyte system. In this study, we encapsulated proteins within nonfouling polyzwitterionic shells, which offer the protein with the significantly improved stability, reduced phagocytosis, and prolonged circulation time. Exemplified with urate oxidase (UOx), the encapsulated UOx noted as n­(UOx) could facilely escape from macrophage uptake in medium with or without serum. In contrast, the native protein rapidly induced high-uptake and accumulated into the macrophages under the same conditions. Moreover, the similar result is also observed in liver-resident kupffer cells, which were isolated from the mice after treated with fluorescent-labeled native UOx and n­(UOx). Furthermore, n­(UOx) exhibited significantly improved stability in vivo and a more than eightfold improvement in circulation time when compared with native UOx. Because of its superior ability to reduce macrophage uptake and promote the circulation time, this technique also makes it an ideal candidate for the enhancement of targeting efficiency in drug delivery and biodetection, which affords an alternative method for diverse medical applications

High-Performance Sodium-Ion Pseudocapacitors Based on Hierarchically Porous Nanowire Composites

Electrical energy storage plays an increasingly important role in modern society. Current energy storage methods are highly dependent on lithium-ion energy storage devices, and the expanded use of these technologies is likely to affect existing lithium reserves. The abundance of sodium makes Na-ion-based devices very attractive as an alternative, sustainable energy storage system. However, electrodes based on transition-metal oxides often show slow kinetics and poor cycling stability, limiting their use as Na-ion-based energy storage devices. The present paper details a new direction for electrode architectures for Na-ion storage. Using a simple hydrothermal process, we synthesized interpenetrating porous networks consisting of layer-structured V₂O₅ nanowires and carbon nanotubes (CNTs). This type of architecture provides facile sodium insertion/extraction and fast electron transfer, enabling the fabrication of high-performance Na-ion pseudocapacitors with an organic electrolyte. Hybrid asymmetric capacitors incorporating the V₂O₅/CNT nanowire composites as the anode operated at a maximum voltage of 2.8 V and delivered a maximum energy of ∼40 Wh kg^–1, which is comparable to Li-ion-based asymmetric capacitors. The availability of capacitive storage based on Na-ion systems is an attractive, cost-effective alternative to Li-ion systems

Modulation of Gene Expression by Polymer Nanocapsule Delivery of DNA Cassettes Encoding Small RNAs

<div><p>Small RNAs, including siRNAs, gRNAs and miRNAs, modulate gene expression and serve as potential therapies for human diseases. Delivery to target cells remains the fundamental limitation for use of these RNAs in humans. To address this challenge, we have developed a nanocapsule delivery technology that encapsulates small DNA molecules encoding RNAs into a small (30nm) polymer nanocapsule. For proof of concept, we transduced DNA expression cassettes for three small RNAs. In one application, the DNA cassette encodes an shRNA transcriptional unit that downregulates CCR5 and protects from HIV-1 infection. The DNA cassette nanocapsules were further engineered for timed release of the DNA cargo for prolonged knockdown of CCR5. Secondly, the nanocapsules provide an efficient means for delivery of gRNAs in the CRISPR/Cas9 system to mutate integrated HIV-1. Finally, delivery of microRNA-125b to mobilized human CD34+ cells enhances survival and expansion of the CD34+ cells in culture.</p></div

Preparation and characterization of DNA cassette nanocapsuels.

<p>a) Illustration of the synthesis and delivery of DNA cassette nanocapsules: 1) self-assembly of monomers, crosslinkers and DNA cassette; II): formation of DNA cassette nanocapsules through <i>in-situ</i> polymerization; III): delivery; IV): release of DNA cassette and expression of small RNAs. b) (A) Gel electrophoresis image of DNA cassette (a: for CCR5 shRNA; b: for EGFP shRNA). (B) TEM image of DNA cassettes (Scale bar = 100nm); (C) TEM image of DNA cassette nanocapsules (molar ratio of DNA to 3 reactants shown in Fig 1 as A,B,C = 1:750:750:30) c) HEK-293T cells transduced with Alexa592-labelled DNA cassette nanocapsules. (A) Optical image; (B) Fluorescence image; (C) Flow cytometry of 293T cells. D) Knockdown of CCR5-luciferase by CCR5-shRNA DNA cassette nanocapsule100ng DNA per 2.5 x104 cells in 100uL. Cells were dosed with Alexa592-labelled DNA cassette nanocapsules at 100nM for 4 h. Then nanocapsules were removed by washing 3 times with PBS. After trypsinization, cells were pictured with Leica Zeiss Axio Observer and also analyzed by a flow cytometer.</p

Nanocapsule delivery of shRNAs to downregulate CCR5 and inhibit HIV-1 infection.

<p>a) Sensitivity of DNA cassette to DNase I. DNA cassette complexed with lipofectamine and DNA nanocapsules were incubated for 1 hour without DNase I and with DNase I, respectively. b) Viability of HEK-293T cells transduced with CCR5 DNA cassette nanocapsules. HEK-293T cells were treated with DNA cassette nanocapsules at 0, 0.1, 0.2 and 0.4 pmol for 4 h at 37°C in 100uL of serum-free medium. After 24 h, cell viability was determined with CytoToxGlo kit using a 96-well plate reader. c) Knockdown of CCR5-Luciferase in HEK-293T cells by CCR5 DNA cassette nanocapsules and CCR5 siRNA lipofectamine complex. d) Down-regulation of CCR5 in 293 cells by sh1005 DNA cassette nanocapsules with different ratios (5:0; 3:2; 2:3 and 1:4) of degradable crosslinker (Glycerol 1,3-diglycerolate diacrylate, GDGDA) to non-degradable crosslinker (N,N’-methylenesbisacrylamide, BIS). On day 0, cells were transduced with DNA cassette nanocapsules for 4 hours. On day 3, 5 and 9, cells were stained and analyzed by flow cytometry. e) Inhibition of viral infection of Affinofile cells by sh1005 DNA cassette nanocapsules with different ratios (5:0; 3:2; 2:3, 1:4 and mixture of 5:0 (50%) and 2:3 (50%)) of degradable crosslinker (GDGDA) to non-degradable crosslinker (BIS). On day 0, Affinofile cells were transduced with DNA cassette nanocapsules for 4 hours and then cultured in the induction medium (6 ng/ml doxy and 5 mM ponA, respectively). On day 3, 5 and 9, Affinofile cells were seeded into 96-well plates at a density of 10^4 cells/well. 24 hours later, the induction medium was removed and gently replaced with 100ul of fresh, warmed culture medium containing env-pseudotyped virus. The infection plates were spinoculated at 2,000 rpm for 2 hours at 37°C, and then incubated for an additional 48 hours at 37°C. Infection medium was then removed, the cells were lysed, and luciferase activity was assayed using the plate reader.</p

Nanocapsule delivery of miRNA to increase survival and expansion of hematopoietic stem/progenitor cells (HSPC).

<p>a) Flow cytometry of mobilized CD34+ cells incubated with fluorescence-labeled miR-125b DNA nanocapsules for 4 hours; b) <i>Ex-vivo</i> expansion of cytokine-mobilized CD34+ cells cultured with 50ng/mL SCF, 50ng/mL Flt-3L, and 50ng/mL TPO for 6 days after delivery of miR-125b DNA nanocapsules and control DNA nanocapsules. Annexin V staining of mobilized CD34+ cells c) without nanocapsules, d) with miR-125b DNA nanocapsules and e) with control DNA nanocapsules 24 hours later after treatment of staurosporine for 4 hours. Microscopic images of mobilized CD34+ cells f) without nanocapsules, g) with miR-125b DNA nanocapsules and h) transduced with miR-125b expressing lentiviral vector, cultured and expanded for 7 days.</p

data for DRD4-ideology _Ebstein PRSB 2014

data for DRD4-ideology _Ebstein PRSB 201

Nanocapsule delivery of gRNAs to excise the HIV-1 provirus by CRISPR mutagenesis.

<p>a) Schematic illustrating the position of two adjacent gRNAs directed to the HIV-1 LTR. b) A time course for knockout of EGFP expression was determined by flow cytometry. U6-control shRNA (CCR5-shRNA (a short linear DNA cassette with sh1005 shRNA expressed by U6 promoter)) was used a negative control. Dead cells were excluded by Live/Dead cell viability assay. c) Disruption of EGFP expression in two CEM-T4 clones, each bearing a single integrated EGFP lentiviral vector (FG11 EGFP). The U6-gRNA DNA cassette was encapsulated by nanocapsules, the hCas9 plasmid was condensed by PEI. The integration site of the lentiviral vector in Clone 1 is at chromosome (chr) 7 (-16350165). The integration site in Clone 2 is at chromosome (chr) 3 (+37026604). U6-control shRNA was used as a negative control. Dead cells were excluded by Live/Dead cell viability assay. Transduction efficiency is estimated to be 69.7% by transducing a Rhodamine B-labeled DNA cassette. d) EGFP expression after CRISPR/Cas9 nickase treatment. CEM-T4 cells were co-transduced with PEI condensed hCas9 nickase and gRNA nanocapsules. Dead cells were excluded by Live/Dead cell viability assay. e) Sequence analysis of the target site in the TAR region of LTR after the gRNA1/Cas9 treatment. DNA sequence demonstrated a single remaining LTR footprint resulting from proviral excision. The target sequence is indicated in red. The host cell genome sequence with integrated HIV vector is indicated as wild type (WT) on the top.</p

In Situ High-Level Nitrogen Doping into Carbon Nanospheres and Boosting of Capacitive Charge Storage in Both Anode and Cathode for a High-Energy 4.5 V Full-Carbon Lithium-Ion Capacitor

To circumvent the imbalances of electrochemical kinetics and capacity between Li⁺ storage anodes and capacitive cathodes for lithium-ion capacitors (LICs), we herein demonstrate an efficient solution by boosting the capacitive charge-storage contributions of carbon electrodes to construct a high-performance LIC. Such a strategy is achieved by the in situ and high-level doping of nitrogen atoms into carbon nanospheres (ANCS), which increases the carbon defects and active sites, inducing more rapidly capacitive charge-storage contributions for both Li⁺ storage anodes and PF₆^– storage cathodes. High-level nitrogen-doping-induced capacitive enhancement is successfully evidenced by the construction of a symmetric supercapacitor using commercial organic electrolytes. Coupling a pre-lithiated ANCS anode with a fresh ANCS cathode enables a full-carbon LIC with a high operating voltage of 4.5 V and high energy and power densities thereof. The assembled LIC device delivers high energy densities of 206.7 and 115.4 Wh kg^–1 at power densities of 0.225 and 22.5 kW kg^–1, respectively, as well as an unprecedented high-power cycling stability with only 0.0013% capacitance decay per cycle within 10 000 cycles at a high power output of 9 kW kg^–1