Graphene-Templated Synthesis of Magnetic Metal Organic Framework Nanocomposites for Selective Enrichment of Biomolecules

Successful control of homogeneous and complete coating of graphene or graphene-based composites with well-defined metal organic framework (MOF) layers is a great challenge. Herein, novel magnetic graphene MOF composites were constructed via a simple strategy for self-assembly of well-distributed, dense, and highly porous MOFs on both sides of graphene nanosheets. Graphene functionalized with magnetic nanoparticles and carboxylic groups on both sides was explored as the backbone and template to direct the controllable self-assembly of MOFs. The prepared composite materials have a relatively high specific surface area (345.4 m² g^–1), and their average pore size is measured to be 3.2 nm. Their relatively high saturation magnetization (23.8 emu g^–1) indicates their strong magnetism at room temperature. Moreover, the multifunctional composite was demonstrated to be a highly effective affinity material in selective extraction and separation of low-concentration biomolecules from biological samples, in virtue of the size-selection property of the unique porous structure and the excellent affinity of the composite materials. Besides providing a solution for the construction of well-defined functional graphene-based MOFs, this work could also contribute to selective extraction of biomolecules, in virtue of the universal affinity between immobilized metal ions and biomolecules

Myosin-Driven Intercellular Transportation of Wheat Germ Agglutinin Mediated by Membrane Nanotubes between Human Lung Cancer Cells

Membrane nanotubes can facilitate direct intercellular communication between cells and provide a unique channel for intercellular transfer of cellular contents. However, the transport mechanisms of membrane nanotubes remain poorly understood between cancer cells. Also largely unknown is the transport pattern mediated by membrane nanotubes. In this work, wheat germ agglutinin (WGA), a widely used drug carrier and potential antineoplastic drug, was labeled with quantum dots (QDs-WGA) as a model for exploring the intercellular transportation <i>via</i> membrane nanotubes. We found that membrane nanotubes allowed effective transfer of QDs-WGA. Long-term single-particle tracking indicated that the movements of QDs-WGA exhibited a slow and directed motion pattern in nanotubes. Significantly, the transport of QDs-WGA was driven by myosin molecular motors in an active and unidirectional manner. These results contribute to a better understanding of cell-to-cell communication for cancer research

Myosin-Driven Intercellular Transportation of Wheat Germ Agglutinin Mediated by Membrane Nanotubes between Human Lung Cancer Cells

Membrane nanotubes can facilitate direct intercellular communication between cells and provide a unique channel for intercellular transfer of cellular contents. However, the transport mechanisms of membrane nanotubes remain poorly understood between cancer cells. Also largely unknown is the transport pattern mediated by membrane nanotubes. In this work, wheat germ agglutinin (WGA), a widely used drug carrier and potential antineoplastic drug, was labeled with quantum dots (QDs-WGA) as a model for exploring the intercellular transportation <i>via</i> membrane nanotubes. We found that membrane nanotubes allowed effective transfer of QDs-WGA. Long-term single-particle tracking indicated that the movements of QDs-WGA exhibited a slow and directed motion pattern in nanotubes. Significantly, the transport of QDs-WGA was driven by myosin molecular motors in an active and unidirectional manner. These results contribute to a better understanding of cell-to-cell communication for cancer research

Myosin-Driven Intercellular Transportation of Wheat Germ Agglutinin Mediated by Membrane Nanotubes between Human Lung Cancer Cells

Membrane nanotubes can facilitate direct intercellular communication between cells and provide a unique channel for intercellular transfer of cellular contents. However, the transport mechanisms of membrane nanotubes remain poorly understood between cancer cells. Also largely unknown is the transport pattern mediated by membrane nanotubes. In this work, wheat germ agglutinin (WGA), a widely used drug carrier and potential antineoplastic drug, was labeled with quantum dots (QDs-WGA) as a model for exploring the intercellular transportation <i>via</i> membrane nanotubes. We found that membrane nanotubes allowed effective transfer of QDs-WGA. Long-term single-particle tracking indicated that the movements of QDs-WGA exhibited a slow and directed motion pattern in nanotubes. Significantly, the transport of QDs-WGA was driven by myosin molecular motors in an active and unidirectional manner. These results contribute to a better understanding of cell-to-cell communication for cancer research

Verrucaria indet.

Membrane nanotubes can facilitate direct intercellular communication between cells and provide a unique channel for intercellular transfer of cellular contents. However, the transport mechanisms of membrane nanotubes remain poorly understood between cancer cells. Also largely unknown is the transport pattern mediated by membrane nanotubes. In this work, wheat germ agglutinin (WGA), a widely used drug carrier and potential antineoplastic drug, was labeled with quantum dots (QDs-WGA) as a model for exploring the intercellular transportation <i>via</i> membrane nanotubes. We found that membrane nanotubes allowed effective transfer of QDs-WGA. Long-term single-particle tracking indicated that the movements of QDs-WGA exhibited a slow and directed motion pattern in nanotubes. Significantly, the transport of QDs-WGA was driven by myosin molecular motors in an active and unidirectional manner. These results contribute to a better understanding of cell-to-cell communication for cancer research

Myosin-Driven Intercellular Transportation of Wheat Germ Agglutinin Mediated by Membrane Nanotubes between Human Lung Cancer Cells

Membrane nanotubes can facilitate direct intercellular communication between cells and provide a unique channel for intercellular transfer of cellular contents. However, the transport mechanisms of membrane nanotubes remain poorly understood between cancer cells. Also largely unknown is the transport pattern mediated by membrane nanotubes. In this work, wheat germ agglutinin (WGA), a widely used drug carrier and potential antineoplastic drug, was labeled with quantum dots (QDs-WGA) as a model for exploring the intercellular transportation <i>via</i> membrane nanotubes. We found that membrane nanotubes allowed effective transfer of QDs-WGA. Long-term single-particle tracking indicated that the movements of QDs-WGA exhibited a slow and directed motion pattern in nanotubes. Significantly, the transport of QDs-WGA was driven by myosin molecular motors in an active and unidirectional manner. These results contribute to a better understanding of cell-to-cell communication for cancer research

Myosin-Driven Intercellular Transportation of Wheat Germ Agglutinin Mediated by Membrane Nanotubes between Human Lung Cancer Cells

Membrane nanotubes can facilitate direct intercellular communication between cells and provide a unique channel for intercellular transfer of cellular contents. However, the transport mechanisms of membrane nanotubes remain poorly understood between cancer cells. Also largely unknown is the transport pattern mediated by membrane nanotubes. In this work, wheat germ agglutinin (WGA), a widely used drug carrier and potential antineoplastic drug, was labeled with quantum dots (QDs-WGA) as a model for exploring the intercellular transportation <i>via</i> membrane nanotubes. We found that membrane nanotubes allowed effective transfer of QDs-WGA. Long-term single-particle tracking indicated that the movements of QDs-WGA exhibited a slow and directed motion pattern in nanotubes. Significantly, the transport of QDs-WGA was driven by myosin molecular motors in an active and unidirectional manner. These results contribute to a better understanding of cell-to-cell communication for cancer research

Myosin-Driven Intercellular Transportation of Wheat Germ Agglutinin Mediated by Membrane Nanotubes between Human Lung Cancer Cells

Membrane nanotubes can facilitate direct intercellular communication between cells and provide a unique channel for intercellular transfer of cellular contents. However, the transport mechanisms of membrane nanotubes remain poorly understood between cancer cells. Also largely unknown is the transport pattern mediated by membrane nanotubes. In this work, wheat germ agglutinin (WGA), a widely used drug carrier and potential antineoplastic drug, was labeled with quantum dots (QDs-WGA) as a model for exploring the intercellular transportation <i>via</i> membrane nanotubes. We found that membrane nanotubes allowed effective transfer of QDs-WGA. Long-term single-particle tracking indicated that the movements of QDs-WGA exhibited a slow and directed motion pattern in nanotubes. Significantly, the transport of QDs-WGA was driven by myosin molecular motors in an active and unidirectional manner. These results contribute to a better understanding of cell-to-cell communication for cancer research

Dissecting the Factors Affecting the Fluorescence Stability of Quantum Dots in Live Cells

Labeling and imaging of live cells with quantum dots (QDs) has attracted great attention in the biomedical field over the past two decades. Maintenance of the fluorescence of QDs in a biological environment is crucial for performing long-term cell tracking to investigate the proliferation and functional evolution of cells. The cell-penetrating peptide transactivator of transcription (TAT) is a well-studied peptide to efficiently enhance the transmembrane delivery. Here, we used TAT peptide-conjugated QDs (TAT–QDs) as a model system to examine the fluorescence stability of QDs in live cells. By confocal microscopy, we found that TAT–QDs were internalized into cells by endocytosis, and transported into the cytoplasm via the mitochondria, Golgi apparatus, and lysosomes. More importantly, the fluorescence of TAT–QDs in live cells was decreased mainly by cell proliferation, and the low pH value in the lysosomes could also lower the fluorescence intensity of intracellular QDs. Quantitative analysis of the amount of QDs in the extracellular region and whole cells indicated that the exocytosis was not the primary cause of fluorescence decay of intracellular QDs. This work facilitates a better understanding of the fluorescence stability of QDs for cell imaging and long-term tracking in live cells. Also, it provides insights into the utility of TAT for transmembrane transportation, and the preparation and modification of QDs for cell imaging and tracking

Magnetic Affinity Microspheres with Meso-/Macroporous Shells for Selective Enrichment and Fast Separation of Phosphorylated Biomolecules

The flowerlike multifunctional affinity microspheres prepared by a facile solvothermal synthesis and subsequent calcination process consist of magnetic cores and hierarchical meso-/macroporous TiO₂ shells. The hierarchical porous structure of the flowerlike affinity microspheres is constructed by the macroporous shell from the stacked mesoporous nanopetals which are assembled by small crystallites. The affinity microspheres have a relatively large specific surface area of 50.45 m² g^–1 and superparamagnetism with a saturation magnetization (<i>M</i>_s) value of 30.1 emu g^–1. We further demonstrate that they can be applied for rapid and effective purification of phosphoproteins, in virtue of their selective affinity, porous structure, and strong magnetism. In addition, the affinity microspheres can also be used for enrichment of phosphopeptides, and the selectivity is greatly improved due to the increase of mass transport and prevention of the possible “shadow effect” resulting from the smaller and deeper pores by taking advantage of the unique porous structure. Overall, this work will be highly beneficial for future applications in the isolation and identification of phosphorylated biomolecules