Novel magnetic multicore nanoparticles designed for MPI and other biomedical applications: From synthesis to first in vivo studies

Pegylation, as a simple procedure to attach hydrophilic polyethylene glycol (PEG) onto therapeutic molecule or drug carriers has been utilized widely to deliver small molecules, proteins and peptides. It was first reported in 1970s by Dr. Frank Davis of Rutgers University and Dr. Abuchowsky in the studies of PEG modified albumin and catalase. The significance of this method at that time was able to successfully modify the enzyme with better hydrophilicity but also keep the enzymatic activity. The employment of PEG has provided superior stability of drug delivery systems (DDS) and enhanced the circulation time in vivo. Simple conjugation of PEG chains with various molecular weights enables the possibility to regulate the properties of desired DDS and led to important contribution in targeting therapy and diagnosis. Pegylation has been reported to be able to protect peptides by shielding antigenic epitopes from reticuloendothelial (RES) clearance and avoid enzymes being recognized by immune system and avoid early degradation. In addition, utilization of PEG in DDS are reported with enhanced delivery efficiency, prolonged circulation time and improved stability, especially active enzymes and peptides drug delivery. In this paper, we will conclude current studies about Pegylated DDS and their biomedical applications from both in vitro and in vivo studies.

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Gold nanoclusters for biomedical applications: toward in vivo studies

Journal of Materials Chemistry B ◽

10.1039/c9tb02767j ◽

2020 ◽

Vol 8 (11) ◽

pp. 2216-2232 ◽

Cited By ~ 13

Author(s):

Estelle Porret ◽

Xavier Le Guével ◽

Jean-Luc Coll

Keyword(s):

Biomedical Applications ◽

Gold Nanoclusters ◽

In Vivo Studies ◽

Therapeutic Properties ◽

Theranostic Agents

In parallel with the rapidly growing and widespread use of nanomedicine in the clinic, we are also witnessing the development of so-called theranostic agents that combine diagnostic and therapeutic properties.

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Pd-based bimetallic catalysts for HET-PHIP

10.5194/mr-2021-5 ◽

2021 ◽

Author(s):

Dudari B. Burueva ◽

Aleksandr Y. Stakheev ◽

Igor V. Koptyug

Keyword(s):

Bimetallic Catalysts ◽

Biomedical Applications ◽

Heterogeneous Catalysts ◽

In Vivo Studies ◽

Catalytically Active ◽

Spin Isomers ◽

Heterogeneous Hydrogenation ◽

H2 Addition ◽

Free Gases

Abstract. Production of hyperpolarized catalyst-free gases and liquids by heterogeneous hydrogenation with parahydrogen (HET-PHIP) can be useful for various technical as well as biomedical applications, including in vivo studies, investigations of mechanisms of industrially important catalytic processes, enrichment of nuclear spin isomers of polyatomic gases, and more. In this regard, the wide systematic search for heterogeneous catalysts effective in pairwise H2 addition required for the observation of PHIP effects is crucial. Here in this work we demonstrate the competitive advantage of Pd-based bimetallic catalysts for HET-PHIP. The dilution of catalytically active Pd with less active Ag or In atoms provides the formation of atomically dispersed Pd1 sites on the surface of Pd-based bimetallic catalysts, which are significantly more selective toward pairwise H2 addition compared to the monometallic Pd. Furthermore, the choice of the dilution metal (Ag or In) has a pronounced effect on the efficiency of bimetallic catalysts in HET-PHIP, as revealed by comparing Pd-Ag and Pd-In bimetallic catalysts.

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Additively manufactured titanium alloys and effect of hydroxyapatite coating for biomedical applications: A review

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/1464420720942560 ◽

2020 ◽

Vol 234 (11) ◽

pp. 1450-1460

Author(s):

Franklin Anene ◽

Jaafar Aiza ◽

Ismail Zainol ◽

Azmah Hanim ◽

Mohd Tahir Suraya

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

Titanium Alloys ◽

Biomedical Applications ◽

Hydroxyapatite Coating ◽

In Vivo Studies ◽

Processing Technologies ◽

Treatment Processes

Metallic implants are extensively used to treat a spectrum of orthopaedic related disorders. Among the metals, titanium and its alloys are considered most excellent and indispensable material for the production of orthopaedic implants regarding their sterling mechanical properties and exceptional biocompatibility. Recently, rapid progress in developing non-toxic titanium-based alloys with modulus similar to that of human bone has inspired researchers globally. Thus, many studies have focused on titanium alloys, their heat treatment processes and several processing technologies. Additive manufacturing has been designed to enhance their mechanical properties tailored towards biomedical applications. Inarguably, the need to further improve on the implant’s biocompatibility with bodily environment for optimum service life is of great importance. Hence, hydroxyapatite coating provides an improvement as demonstrated by in vitro as well as in vivo studies. The present article critically reviews, based on recent scientific literatures, the progress made thus far in the development of titanium-based alloys, additive manufacturing processes and their heat and surface treatments tailored towards biomedical applications.

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Synthesis of Chitosan Beads Incorporating Graphene Oxide/Titanium Dioxide Nanoparticles for In Vivo Studies

Molecules ◽

10.3390/molecules25102308 ◽

2020 ◽

Vol 25 (10) ◽

pp. 2308

Author(s):

Carlos David Grande Tovar ◽

Jorge Iván Castro ◽

Carlos Humberto Valencia ◽

Paula A. Zapata ◽

Moisés A. Solano ◽

...

Keyword(s):

Titanium Dioxide ◽

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Biomedical Applications ◽

Titanium Dioxide Nanoparticles ◽

Healing Process ◽

Antimicrobial Property ◽

In Vivo Studies ◽

Cell Regeneration

Scaffold development for cell regeneration has increased in recent years due to the high demand for more efficient and biocompatible materials. Nanomaterials have become a critical alternative for mechanical, thermal, and antimicrobial property reinforcement in several biopolymers. In this work, four different chitosan (CS) bead formulations crosslinked with glutaraldehyde (GLA), including titanium dioxide nanoparticles (TiO2), and graphene oxide (GO) nanosheets, were prepared with potential biomedical applications in mind. The characterization of by FTIR spectroscopy, X-ray photoelectron spectroscopy (XRD), thermogravimetric analysis (TGA), energy-dispersive spectroscopy (EDS) and scanning electron microscopy (SEM), demonstrated an efficient preparation of nanocomposites, with nanoparticles well-dispersed in the polymer matrix. In vivo, subdermal implantation of the beads in Wistar rat′s tissue for 90 days showed a proper and complete healing process without any allergenic response to any of the formulations. Masson′s trichrome staining of the histological implanted tissues demonstrated the presence of a group of macrophage/histiocyte compatible cells, which indicates a high degree of biocompatibility of the beads. The materials were very stable under body conditions as the morphometry studies showed, but with low resorption percentages. These high stability beads could be used as biocompatible, resistant materials for long-term applications. The results presented in this study show the enormous potential of these chitosan nanocomposites in cell regeneration and biomedical applications.

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Iron Oxide-Based Magneto-Optical Nanocomposites for In Vivo Biomedical Applications

Biomedicines ◽

10.3390/biomedicines9030288 ◽

2021 ◽

Vol 9 (3) ◽

pp. 288

Author(s):

Nisha Lamichhane ◽

Shalini Sharma ◽

Parul ◽

Anita Verma ◽

Indrajit Roy ◽

...

Keyword(s):

Iron Oxide ◽

Targeted Delivery ◽

Biomedical Applications ◽

Real Life ◽

Optical Probe ◽

In Vivo Studies ◽

Contrast Imaging ◽

Optical Probes ◽

High Contrast Imaging

Iron oxide nanoparticles (IONPs) have played a pivotal role in the development of nanomedicine owing to their versatile functions at the nanoscale, which facilitates targeted delivery, high contrast imaging, and on-demand therapy. Some biomedical inadequacies of IONPs on their own, such as the poor resolution of IONP-based Magnetic Resonance Imaging (MRI), can be overcome by co-incorporating optical probes onto them, which can be either molecule- or nanoparticulate-based. Optical probe incorporated IONPs, together with two prominent non-ionizing radiation sources (i.e., magnetic field and light), enable a myriad of biomedical applications from early detection to targeted treatment of various diseases. In this context, many research articles are in the public domain on magneto-optical nanoparticles; discussed in detail are fabrication strategies for their application in the biomedical field; however, lacking is a comprehensive review on real-life applications in vivo, their toxicity, and the prospect of bench-to-bedside clinical studies. Therefore, in this review, we focused on selecting such important nanocomposites where IONPs become the magnetic component, conjugated with various types of optical probes; we clearly classified them into class 1 to class 6 categories and present only in vivo studies. In addition, we briefly discuss the potential toxicity of such nanocomposites and their respective challenges for clinical translations.

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Biomedical applications: Pitfalls in the practice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100169626 ◽

1994 ◽

Vol 52 ◽

pp. 378-379

Author(s):

J. D. Shelburne ◽

Peter Ingram ◽

Victor L. Roggli ◽

Ann LeFurgey

Keyword(s):

Operating Room ◽

Liquid Nitrogen ◽

Lung Tissue ◽

Biomedical Applications ◽

Microprobe Analysis ◽

Tissue Sample ◽

Cellular Level ◽

Tissue Samples ◽

Asbestos Fibers

At present most medical microprobe analysis is conducted on insoluble particulates such as asbestos fibers in lung tissue. Cryotechniques are not necessary for this type of specimen. Insoluble particulates can be processed conventionally. Nevertheless, it is important to emphasize that conventional processing is unacceptable for specimens in which electrolyte distributions in tissues are sought. It is necessary to flash-freeze in order to preserve the integrity of electrolyte distributions at the subcellular and cellular level. Ideally, biopsies should be flash-frozen in the operating room rather than being frozen several minutes later in a histology laboratory. Electrolytes will move during such a long delay. While flammable cryogens such as propane obviously cannot be used in an operating room, liquid nitrogen-cooled slam-freezing devices or guns may be permitted, and are the best way to achieve an artifact-free, accurate tissue sample which truly reflects the in vivo state. Unfortunately, the importance of cryofixation is often not understood. Investigators bring tissue samples fixed in glutaraldehyde to a microprobe laboratory with a request for microprobe analysis for electrolytes.

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Biological and biomedical applications of collagenous biomaterials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161849 ◽

1990 ◽

Vol 48 (3) ◽

pp. 856-857

Author(s):

Yasushi P. Kato ◽

Michael G. Dunn ◽

Frederick H. Silver ◽

Arthur J. Wasserman

Keyword(s):

Biomedical Applications ◽

Soft Tissues ◽

Collagen Fibers ◽

Bone Collagen ◽

Cover Slip ◽

Fibroblast Migration ◽

Cellular Expression ◽

Defect Repair

Collagenous biomaterials have been used for growing cells in vitro as well as for augmentation and replacement of hard and soft tissues. The substratum used for culturing cells is implicated in the modulation of phenotypic cellular expression, cellular orientation and adhesion. Collagen may have a strong influence on these cellular parameters when used as a substrate in vitro. Clinically, collagen has many applications to wound healing including, skin and bone substitution, tendon, ligament, and nerve replacement. In this report we demonstrate two uses of collagen. First as a fiber to support fibroblast growth in vitro, and second as a demineralized bone/collagen sponge for radial bone defect repair in vivo.For the in vitro study, collagen fibers were prepared as described previously. Primary rat tendon fibroblasts (1° RTF) were isolated and cultured for 5 days on 1 X 15 mm sterile cover slips. Six to seven collagen fibers, were glued parallel to each other onto a circular cover slip (D=18mm) and the 1 X 15mm cover slip populated with 1° RTF was placed at the center perpendicular to the collagen fibers. Fibroblast migration from the 1 x 15mm cover slip onto and along the collagen fibers was measured daily using a phase contrast microscope (Olympus CK-2) with a calibrated eyepiece. Migratory rates for fibroblasts were determined from 36 fibers over 4 days.

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