The Experts below are selected from a list of 1566 Experts worldwide ranked by ideXlab platform

Beata Chertok - One of the best experts on this subject based on the ideXlab platform.

  • Size-Controlled Iron Oxide Nanoplatforms with Lipidoid-Stabilized Shells for Efficient Magnetic Resonance Imaging-Trackable Lymph Node Targeting and High-Capacity Biomolecule Display
    ACS applied materials & interfaces, 2018
    Co-Authors: Ryan M. Clauson, Mingsheng Chen, Lindsay M. Scheetz, Brendan Berg, Beata Chertok
    Abstract:

    Nanoplatforms for Biomolecule Delivery to the lymph nodes have attracted considerable interest as vectors for immunotherapy. Core-shell iron oxide nanoparticles are particularly appealing because of their potential as theranostic magnetic resonance imaging (MRI)-trackable vehicles for Biomolecule Delivery. The key challenge for utilizing iron oxide nanoparticles in this capacity is control of their coating shells to produce particles with predictable size. Size determines both the carrier capacity for Biomolecule display and the carrier ability to target the lymph nodes. In this study, we develop a novel coating method to produce core-shell iron oxide nanoparticles with controlled size. We utilize lipidlike molecules to stabilize self-assembled lipid shells on the surface of iron oxide nanocrystals, allowing the formation of consistent coatings on nanocrystals of varying size (10-40 nm). We further demonstrate the feasibility of leveraging the ensuing control of nanocarrier size for optimizing the carrier functionalities. Coated nanoparticles with 10 and 30 nm cores supported Biomolecule display at 10-fold and 200-fold higher capacities than previously reported iron oxide nanoparticles, while preserving monodisperse sub-100 nm size populations. In addition, accumulation of the coated nanoparticles in the lymph nodes could be tracked by MRI and at 1 h post injection demonstrated significantly enhanced lymph node targeting. Notably, lymph node targeting was 9-40 folds higher than that for previously reported nanocarriers, likely due to the ability of these nanoparticles to robustly maintain their sub-100 nm size in vivo. This approach can be broadly applicable for rational design of theranostic nanoplatforms for image-monitored immunotherapy.

  • Size-Controlled Iron Oxide Nanoplatforms with Lipidoid-Stabilized Shells for Efficient Magnetic Resonance Imaging-Trackable Lymph Node Targeting and High-Capacity Biomolecule Display
    2018
    Co-Authors: Ryan M. Clauson, Mingsheng Chen, Lindsay M. Scheetz, Brendan Berg, Beata Chertok
    Abstract:

    Nanoplatforms for Biomolecule Delivery to the lymph nodes have attracted considerable interest as vectors for immunotherapy. Core–shell iron oxide nanoparticles are particularly appealing because of their potential as theranostic magnetic resonance imaging (MRI)-trackable vehicles for Biomolecule Delivery. The key challenge for utilizing iron oxide nanoparticles in this capacity is control of their coating shells to produce particles with predictable size. Size determines both the carrier capacity for Biomolecule display and the carrier ability to target the lymph nodes. In this study, we develop a novel coating method to produce core–shell iron oxide nanoparticles with controlled size. We utilize lipidlike molecules to stabilize self-assembled lipid shells on the surface of iron oxide nanocrystals, allowing the formation of consistent coatings on nanocrystals of varying size (10–40 nm). We further demonstrate the feasibility of leveraging the ensuing control of nanocarrier size for optimizing the carrier functionalities. Coated nanoparticles with 10 and 30 nm cores supported Biomolecule display at 10-fold and 200-fold higher capacities than previously reported iron oxide nanoparticles, while preserving monodisperse sub-100 nm size populations. In addition, accumulation of the coated nanoparticles in the lymph nodes could be tracked by MRI and at 1 h post injection demonstrated significantly enhanced lymph node targeting. Notably, lymph node targeting was 9–40 folds higher than that for previously reported nanocarriers, likely due to the ability of these nanoparticles to robustly maintain their sub-100 nm size in vivo. This approach can be broadly applicable for rational design of theranostic nanoplatforms for image-monitored immunotherapy

Jie Chen - One of the best experts on this subject based on the ideXlab platform.

  • Study of interactions between cells and microbubbles in high speed centrifugation field for Biomolecule Delivery
    2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2014
    Co-Authors: Chuan He, Jie Chen
    Abstract:

    Biomolecule Delivery has a very wide range of applications in biology and medicine. In this study, a microbubble based Delivery method was developed. In a high centrifugation field, cells deform and collide with microbubbles to induce intracellular pathways on cell membranes. As a result, biomaterials can then easily enter cells. Experimental results show that this Delivery method can achieve high Delivery efficiency. Simulation results showed that cells with more deformed structure experienced higher strain on cell membranes than cells with less deformed structure. The models can help explain how centrifugation affects cell membrane permeability. By controlling cell morphology and its mechanical properties, high Biomolecule Delivery efficiency can be achieved.

  • EMBC - Study of interactions between cells and microbubbles in high speed centrifugation field for Biomolecule Delivery.
    Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Inte, 2014
    Co-Authors: Jie Chen
    Abstract:

    Biomolecule Delivery has a very wide range of applications in biology and medicine. In this study, a microbubble based Delivery method was developed. In a high centrifugation field, cells deform and collide with microbubbles to induce intracellular pathways on cell membranes. As a result, biomaterials can then easily enter cells. Experimental results show that this Delivery method can achieve high Delivery efficiency. Simulation results showed that cells with more deformed structure experienced higher strain on cell membranes than cells with less deformed structure. The models can help explain how centrifugation affects cell membrane permeability. By controlling cell morphology and its mechanical properties, high Biomolecule Delivery efficiency can be achieved.

  • Biomolecule Delivery into canola protoplasts by centrifuging cells with microbubbles
    FEBS letters, 2012
    Co-Authors: Min Huang, James Z. Xing, Jie Chen
    Abstract:

    We have successfully delivered FITC and FITC-Dextran (70, 250 kDa) into canola protoplasts by centrifuging cells with different amounts of microbubbles at variable centrifuge speed. The efficiency is around 90%, while cell viability remains high. Confocal microscopy images show that both FITC and FITC-Dextran are scattered inside the cytoplasm and the cell nucleus. Pores are observed on canola protoplast cell membranes and cell walls when centrifuged with microbubbles, while the membrane of cells centrifuged alone remain intact and smooth. We hypothesize that the collision between the microbubbles and cells or the bursting of microbubbles are the main reasons for the formation of these pores. Biomaterials can diffuse into the cells once the pathway is created.

Molly S Shoichet - One of the best experts on this subject based on the ideXlab platform.

  • a hyaluronan methylcellulose based hydrogel for local cell and Biomolecule Delivery to the central nervous system
    Brain Research Bulletin, 2019
    Co-Authors: Carter J. Teal, Molly S Shoichet
    Abstract:

    Abstract Regenerative medicine strategies rely on exogenous cell transplantation and/or endogenous cell stimulation. Biomaterials can help to increase the regenerative potential of cells and Biomolecules by controlling transplanted cell fate and provide a local, sustained release of Biomolecules. In this review, we describe the use of a hyaluronan/methylcellulose (HAMC)-based hydrogel as a Delivery vehicle to the brain, spinal cord, and retina to promote cellular survival and tissue repair. We discuss various controlled release strategies to prolong the Delivery of factors for neuroprotection. The versatility of this hydrogel for a diversity of applications highlights its potential to enhance cell- and Biomolecule-based treatment strategies.

  • A hyaluronan/methylcellulose-based hydrogel for local cell and Biomolecule Delivery to the central nervous system
    Brain research bulletin, 2019
    Co-Authors: Carter J. Teal, Molly S Shoichet
    Abstract:

    Abstract Regenerative medicine strategies rely on exogenous cell transplantation and/or endogenous cell stimulation. Biomaterials can help to increase the regenerative potential of cells and Biomolecules by controlling transplanted cell fate and provide a local, sustained release of Biomolecules. In this review, we describe the use of a hyaluronan/methylcellulose (HAMC)-based hydrogel as a Delivery vehicle to the brain, spinal cord, and retina to promote cellular survival and tissue repair. We discuss various controlled release strategies to prolong the Delivery of factors for neuroprotection. The versatility of this hydrogel for a diversity of applications highlights its potential to enhance cell- and Biomolecule-based treatment strategies.

  • Designing Peptide and Protein Modified Hydrogels: Selecting the Optimal Conjugation Strategy
    Journal of the American Chemical Society, 2017
    Co-Authors: Stephanie A. Fisher, Alexander E. G. Baker, Molly S Shoichet
    Abstract:

    Hydrogels are used in a wide variety of biomedical applications including tissue engineering, Biomolecule Delivery, cell Delivery, and cell culture. These hydrogels are often designed with a specific biological function in mind, requiring the chemical incorporation of bioactive factors to either mimic extracellular matrix or to deliver a payload to diseased tissue. Appropriate synthetic techniques to ligate bioactive factors, such as peptides and proteins, onto hydrogels are critical in designing materials with biological function. Here, we outline strategies for peptide and protein immobilization. We specifically focus on click chemistry, enzymatic ligation, and affinity binding for transient immobilization. Protein modification strategies have shifted toward site-specific modification using unnatural amino acids and engineered site-selective amino acid sequences to preserve both activity and structure. The selection of appropriate protein immobilization strategies is vital to engineering functional hydr...

  • cell and Biomolecule Delivery for tissue repair and regeneration in the central nervous system
    Journal of Controlled Release, 2014
    Co-Authors: Irja Elliott Donaghue, Michael V Sefton, Molly S Shoichet
    Abstract:

    Abstract Tissue engineering frequently involves cells and scaffolds to replace damaged or diseased tissue. It originated, in part, as a means of effecting the Delivery of Biomolecules such as insulin or neurotrophic factors, given that cells are constitutive producers of such therapeutic agents. Thus cell Delivery is intrinsic to tissue engineering. Controlled release of Biomolecules is also an important tool for enabling cell Delivery since the Biomolecules can enable cell engraftment, modulate inflammatory response or otherwise benefit the behavior of the delivered cells. We describe advances in cell and Biomolecule Delivery for tissue regeneration, with emphasis on the central nervous system (CNS). In the first section, the focus is on encapsulated cell therapy. In the second section, the focus is on Biomolecule Delivery in polymeric nano/microspheres and hydrogels for the nerve regeneration and endogenous cell stimulation. In the third section, the focus is on combination strategies of neural stem/progenitor cell or mesenchymal stem cell and Biomolecule Delivery for tissue regeneration and repair. In each section, the challenges and potential solutions associated with Delivery to the CNS are highlighted.

  • Polymer Scaffolds for Biomaterials Applications
    Macromolecules, 2010
    Co-Authors: Molly S Shoichet
    Abstract:

    Biomaterials have been used extensively in medical, personal care, and food applications, with many similar polymers being used across disciplines. This Perspective will emphasize polymers used in medicine and specifically those designed as scaffolds for use in tissue engineering and regenerative medicine. The areas of active research in tissue engineering include: biomaterials design—incorporation of the appropriate chemical, physical, and mechanical/structural properties to guide cell and tissue organization; cell/scaffold integration—inclusion into the biomaterial scaffold of either cells for transplantation or Biomolecules to attract cells, including stem cells, from the host to promote integration with the tissue after implantation; and Biomolecule Delivery—inclusion of growth factors and/or small molecules or peptides that promote cell survival and tissue regeneration. While a significant and growing area of regenerative medicine involves the stimulation of endogenous stem cells, this Perspective wi...

Min Wang - One of the best experts on this subject based on the ideXlab platform.

  • Selective Laser Sintering and Its Biomedical Applications
    Laser Technology in Biomimetics, 2013
    Co-Authors: Bin Duan, Min Wang
    Abstract:

    Selective laser sintering (SLS), a mature and versatile rapid prototyping (RP) technology, uses a laser beam to selectively sinter powdered materials to form three-dimensional objects, porous or non-porous, according to the computer-aided design which can be based on data obtained from advanced medical imaging technologies such as magnetic resonance imaging (MRI) and computer tomography (CT). In this chapter, major RP technologies suitable for biomedical applications are briefly introduced first. A review is made on SLS, including its working principle, modification of commercial SLS machines for fabricating biomedical products, biomedical SLS materials, and optimization of SLS parameters. Finally, a detailed presentation is given on the biomedical application of SLS, focusing on the fabrication of tissue engineering scaffolds and drug or Biomolecule Delivery vehicles. It is shown that SLS has great potential for many biomimetic and biomedical applications.

  • Selective laser sintering and its application in biomedical engineering
    MRS Bulletin, 2011
    Co-Authors: Bin Duan, Min Wang
    Abstract:

    Rapid prototyping (RP) technologies, which are based on computer-aided design and computer-aided manufacturing, are widely employed in traditional industries. They are capable of achieving extensive and detailed control over the architecture of objects to be formed and therefore are increasingly used in the biomedical engineering field. Selective laser sintering (SLS), a versatile RP technique, uses a laser beam to selectively sinter powdered materials to form three-dimensional objects according to designs that can be based on data obtained from computer-based medical imaging technologies. In this article relating to biomedical applications, the principle, materials, machine modification, and parameter optimization for SLS are reviewed. Biomedical applications of SLS, especially in the fabrication of tissue engineering scaffolds and drug/Biomolecule Delivery vehicles, are presented and discussed. SLS exhibits great potential for many applications in biomedical engineering.

  • Effects of Emulsion Electrospinning Parameters on the Morphology and Structure of Core-Shell Structured PLLA Fibers
    Advanced Materials Research, 2011
    Co-Authors: Xin Zhang, Min Wang
    Abstract:

    Electrospinning is a popular technique for producing micro-or nanofibers for diverse applications including filtration, catalysis, sensors, cosmetics, wound dressing and tissue engineering. In some applications such as controlled drug/Biomolecule Delivery, core-shell structured nanofibers are desired. There are two major electrospinning processes for making core-shell structured fibers: emulsion electrospinning and coaxial electrospinning. In this study, the formation of core-shell structured fibers of poly (L-lactic acid) (PLLA) through emulsion electrospinning was investigated. To study the electrospinability of emulsions based on PLLA solutions, two solvents, pure chloroform and mixed solvent of chloroform and N,N-dimethylformamide, were used separately for making PLLA solutions. In the study of the formation of controlled release systems for Biomolecules, bovine serum albumin, a model protein, was dissolved in de-ionized water to make the water phase in emulsions. In emulsion electrospinning, parameters such as applied voltage, working distance and feeding rate, were systematically investigated. The morphology, diameter and core-shell structure of emulsion electrospun fibers was studied using electron microscopies.

  • Conventional Electrospinning vs. Emulsion Electrospinning: A Comparative Study on the Development of Nanofibrous Drug/Biomolecule Delivery Vehicles
    Advanced Materials Research, 2011
    Co-Authors: Chong Wang, Sze Nga Tong, Yuk Hang Tse, Min Wang
    Abstract:

    Over the past decade, intensive research has been conducted on electrospinning of fibrous tissue engineering scaffolds and their applications in body tissue regeneration. For providing multifunctions and/or enhancing the biological performance, drugs or Biomolecules can be incorporated in electrospun fibers using normally one of these techniques: (1) direct dissolution, (3) emulsion electrospinning, and (3) coaxial electrospinning. In this investigation, for constructing nanofibrous Delivery vehicles, conventional electrospinning using polymer solutions with directly dissolved drugs or Biomolecules and emulsion electrospinning were studied and compared. Bovine serum albumin (BSA) was used as a model protein and the drug was rifamycin, a hydrophobic antibiotic. A poly (lactic-co-glycolic acid) containing the protein or drug was electrospun into fibers. In these two routes of fabricating drug-or Biomolecule-loaded nanofibers, different polymer concentrations and emulsion formulations were investigated. Various aspects of the fibrous Delivery vehicles were investigated using several techniques and the in vitro release behaviour was studied.

Markita P Landry - One of the best experts on this subject based on the ideXlab platform.

  • Nanobiolistics: An Emerging Genetic Transformation Approach.
    Methods in molecular biology (Clifton N.J.), 2020
    Co-Authors: Francis J. Cunningham, Gozde S Demirer, Huan Zhang, Natalie S. Goh, Markita P Landry
    Abstract:

    Biolistic Delivery of biomolecular cargoes to plants with micron-scale projectiles is a well-established technique in plant biotechnology. However, the relatively large micron-scale biolistic projectiles can result in tissue damage, low regeneration efficiency, and create difficulties for the biolistic transformation of isomorphic small cells or subcellular target organelles (i.e., mitochondria and plastids). As an alternative to micron-sized carriers, nanomaterials provide a promising approach for Biomolecule Delivery to plants. While most studies exploring nanoscale biolistic carriers have been carried out in animal cells and tissues, which lack a cell wall, we can nonetheless extrapolate their utility for nanobiolistic Delivery of Biomolecules in plant targets. Specifically, nanobiolistics has shown promising results for use in animal systems, in which nanoscale projectiles yield lower levels of cell and tissue damage while maintaining similar transformation efficiencies as their micron-scale counterparts. In this chapter, we specifically discuss biolistic Delivery of nanoparticles for plant genetic transformation purposes and identify the figures of merit requiring optimization for broad-scale implementation of nanobiolistics in plant genetic transformations.

  • Carbon nanotube–mediated DNA Delivery without transgene integration in intact plants
    Nature Protocols, 2019
    Co-Authors: Gozde S Demirer, Huan Zhang, Natalie S. Goh, Eduardo González-grandío, Markita P Landry
    Abstract:

    This protocol enables gene Delivery in intact plants using high-aspect-ratio carbon nanotubes (CNTs). The procedure contains detailed instructions for the functionalization of CNTs, DNA loading, Delivery, and transgene expression characterization. Exogenous Biomolecule Delivery into plants is difficult because the plant cell wall poses a dominant transport barrier, thereby limiting the efficiency of plant genetic engineering. Traditional DNA Delivery methods for plants suffer from host-species limitations, low transformation efficiencies, tissue damage, or unavoidable and uncontrolled DNA integration into the host genome. We have demonstrated efficient plasmid DNA Delivery into intact plants of several species with functionalized high-aspect-ratio carbon nanotube (CNT) nanoparticles (NPs), enabling efficient DNA Delivery into a variety of non-model plant species (arugula, wheat, and cotton) and resulting in high protein expression levels without transgene integration. Herein, we provide a protocol that can be implemented by plant biologists and adapted to produce functionalized single-walled CNTs (SWNTs) with surface chemistries optimized for Delivery of plasmid DNA in a plant species–independent manner. This protocol describes how to prepare, construct, and optimize polyethylenimine (PEI)-functionalized SWNTs and perform plasmid DNA loading. The authors also provide guidance on material characterization, gene expression evaluation, and storage conditions. The entire protocol, from the covalent functionalization of SWNTs to expression quantification, can be completed in 5 d.

  • Carbon nanotube-mediated DNA Delivery without transgene integration in intact plants.
    Nature protocols, 2019
    Co-Authors: Gozde S Demirer, Huan Zhang, Natalie S. Goh, Eduardo González-grandío, Markita P Landry
    Abstract:

    Exogenous Biomolecule Delivery into plants is difficult because the plant cell wall poses a dominant transport barrier, thereby limiting the efficiency of plant genetic engineering. Traditional DNA Delivery methods for plants suffer from host-species limitations, low transformation efficiencies, tissue damage, or unavoidable and uncontrolled DNA integration into the host genome. We have demonstrated efficient plasmid DNA Delivery into intact plants of several species with functionalized high-aspect-ratio carbon nanotube (CNT) nanoparticles (NPs), enabling efficient DNA Delivery into a variety of non-model plant species (arugula, wheat, and cotton) and resulting in high protein expression levels without transgene integration. Herein, we provide a protocol that can be implemented by plant biologists and adapted to produce functionalized single-walled CNTs (SWNTs) with surface chemistries optimized for Delivery of plasmid DNA in a plant species-independent manner. This protocol describes how to prepare, construct, and optimize polyethylenimine (PEI)-functionalized SWNTs and perform plasmid DNA loading. The authors also provide guidance on material characterization, gene expression evaluation, and storage conditions. The entire protocol, from the covalent functionalization of SWNTs to expression quantification, can be completed in 5 d.

  • DNA nanostructures coordinate gene silencing in mature plants.
    Proceedings of the National Academy of Sciences of the United States of America, 2019
    Co-Authors: Huan Zhang, Gozde S Demirer, Honglu Zhang, Natalie S. Goh, Abhishek J Aditham, Francis J. Cunningham, Chunhai Fan, Markita P Landry
    Abstract:

    Delivery of Biomolecules to plants relies on Agrobacterium infection or biolistic particle Delivery, the former of which is amenable only to DNA Delivery. The difficulty in delivering functional Biomolecules such as RNA to plant cells is due to the plant cell wall, which is absent in mammalian cells and poses the dominant physical barrier to Biomolecule Delivery in plants. DNA nanostructure-mediated Biomolecule Delivery is an effective strategy to deliver cargoes across the lipid bilayer of mammalian cells; however, nanoparticle-mediated Delivery without external mechanical aid remains unexplored for Biomolecule Delivery across the cell wall in plants. Herein, we report a systematic assessment of different DNA nanostructures for their ability to internalize into cells of mature plants, deliver siRNAs, and effectively silence a constitutively expressed gene in Nicotiana benthamiana leaves. We show that nanostructure internalization into plant cells and corresponding gene silencing efficiency depends on the DNA nanostructure size, shape, compactness, stiffness, and location of the siRNA attachment locus on the nanostructure. We further confirm that the internalization efficiency of DNA nanostructures correlates with their respective gene silencing efficiencies but that the endogenous gene silencing pathway depends on the siRNA attachment locus. Our work establishes the feasibility of Biomolecule Delivery to plants with DNA nanostructures and both details the design parameters of importance for plant cell internalization and also assesses the impact of DNA nanostructure geometry for gene silencing mechanisms.

  • DNA Nanostructures Coordinate Gene Silencing in Mature Plants
    2019
    Co-Authors: Huan Zhang, Gozde S Demirer, Honglu Zhang, Natalie S. Goh, Abhishek J Aditham, Francis J. Cunningham, Chunhai Fan, Markita P Landry
    Abstract:

    Plant bioengineering may generate high yielding and stress-resistant crops amidst a changing climate and a growing global population. However, Delivery of Biomolecules to plants relies on Agrobacterium infection or biolistic particle Delivery, the former of which is only amenable to DNA Delivery. The difficulty in delivering functional Biomolecules such as RNA to plant cells is due to the plant cell wall which is absent in mammalian cells and poses the dominant physical barrier to exogenous Biomolecule Delivery in plants. DNA nanostructure-mediated Biomolecule Delivery is an effective strategy to deliver cargoes across the lipid bilayer of mammalian cells, however, nanoparticle-mediated Delivery remains unexplored for passive Biomolecule Delivery across the cell wall in plants. Herein, we report a systematic assessment of different DNA nanostructures for their ability to internalize into cells of mature plants, deliver small interfering RNAs (siRNAs), and effectively silence a constitutively-expressed gene in Nicotiana benthamiana leaves. We show that nanostructure internalization into plant cells and the corresponding gene silencing efficiency depends on the DNA nanostructure size, shape, compactness, stiffness, and location of the siRNA attachment locus on the nanostructure. We further confirm that the internalization efficiency of DNA nanostructures correlates with their respective gene silencing efficiencies, but that the endogenous gene silencing pathway depends on the siRNA attachment locus. Our work establishes the feasibility of Biomolecule Delivery to plants with DNA nanostructures, and details both the design parameters of importance for plant cell internalization, and also assesses the impact of DNA nanostructure geometry for gene silencing mechanisms.