Lactoferrin is a highly safe antibacterial protein found in the human body and in foods. Calcium phosphate (CaP) nanoparticles with immobilized lactoferrin could therefore be useful as intraoral disinfectants for the prevention and treatment of dental infections because CaP is a mineral component of human teeth. In this study, we fabricated CaP nanoparticles with co-immobilized lactoferrin and heparin using a simple one-step coprecipitation process.
View Article and Find Full Text PDFCalcium phosphate (CaP) particles immobilizing antibacterial agents have the potential to be used as dental disinfectants. In this study, we fabricated CaP particles with immobilized ciprofloxacin (CF), a commonly prescribed antibacterial agent, via a coprecipitation process using a supersaturated CaP solution. As the aging time in the coprecipitation process increased from 2 to 24 h, the CaP phase in the resulting particles transformed from amorphous to low-crystalline hydroxyapatite, and their Ca/P elemental ratio, yield, and CF content increased.
View Article and Find Full Text PDFTip-enhanced photoluminescence (TEPL) microscopy allows for the correlation of scanning probe microscopic images and photoluminescent spectra at the nanoscale level in a similar way to tip-enhanced Raman scattering (TERS) microscopy. However, due to the higher cross-section of fluorescence compared to Raman scattering, the diffraction-limited background signal generated by far-field excitation is a limiting factor in the achievable spatial resolution of TEPL. Here, we demonstrate a way to overcome this drawback by using remote excitation TEPL (RE-TEPL).
View Article and Find Full Text PDFGraphene nanoribbons (GNRs), a quasi-one-dimensional form of graphene, have gained tremendous attention due to their potential for next-generation nanoelectronic devices. The chemical unzipping of carbon nanotubes is one of the attractive fabrication methods to obtain single-layered GNRs (sGNRs) with simple and large-scale production. The authors recently found that unzipping from double-walled carbon nanotubes (DWNTs), rather than single- or multi-walled, results in high-yield production of crystalline sGNRs.
View Article and Find Full Text PDFUnderstanding the dynamics and distribution of medicinal drugs in living cells is essential for the design and discovery of treatments. The tools available for revealing this information are, however, extremely limited. Here, we report the application of surface-enhanced Raman scattering (SERS) endoscopy, using plasmonic nanowires as SERS probes, to monitor the intracellular fate and dynamics of a common chemo-drug, doxorubicin, in A549 cancer cells.
View Article and Find Full Text PDFCurrent chemotherapy still suffers from unsatisfactory therapeutic efficacy, multi-drug resistance, and severe adverse effects, thus necessitating the development of techniques to confine chemotherapy drugs in the tumor microenvironment. Herein, we fabricated nanospheres of mesoporous silica (MS) doped with Cu (MS-Cu) and polyethylene glycol (PEG)-coated MS-Cu (PEG-MS-Cu) as exogenous copper supply systems to tumors. The synthesized MS-Cu nanospheres showed diameters of 30-150 nm with Cu/Si molar ratios of 0.
View Article and Find Full Text PDFWe report an efficient photo-induced covalent modification (PICM) of graphene by short-chain fatty acids (SCFAs) with an alkyl chain at the liquid-solid interface for spatially resolved chemical functionalization of graphene. Light irradiation on monolayer graphene under an aqueous solution of the SCFAs with an alkyl chain efficiently introduces sp-hybridized defects, where the reaction rates of PICM are significantly higher than those in pure water. Raman and IR spectroscopy revealed that a high density of methyl, methoxy, and acetate groups is covalently attached to the graphene surface while it was partially oxidized by other oxygen-containing functional groups, such as OH and COOH.
View Article and Find Full Text PDFTip-enhanced Raman scattering (TERS) microscopy is an advanced technique for investigation at the nanoscale that provides topographic and chemical information simultaneously. The TERS probe plays a crucial role in the microscopic performance. In the recent past, the development of silver nanowire (AgNW) based TERS probes solved the main tip fabrication issues, such as low mechanical strength and reproducibility.
View Article and Find Full Text PDFWe report a facile all-optical method for spatially resolved and reversible chemical modification of a graphene monolayer. A tightly focused laser on graphene under water introduces an sp-type chemical defect by photo-oxidation. The sp-type defects can be reversibly restored to sp carbon centers by the same laser with higher intensity.
View Article and Find Full Text PDFInvited for the cover of this issue are Daisuke Tanaka at Kwansei Gakuin University and co-workers at Kwansei Gakuin University, Hokkaido University, Kyoto University, Japan and KU Leuven, Belgium. The image is a depiction of exploring the desired crystal by decision tree analysis. Read the full text of the article at 10.
View Article and Find Full Text PDFNovel metal-organic frameworks containing lanthanide double-layer-based secondary building units (KGF-3) were synthesized by using machine learning (ML). Isolating pure KGF-3 was challenging, and the synthesis was not reproducible because impurity phases were frequently obtained under the same synthetic conditions. Thus, dominant factors for the synthesis of KGF-3 were identified, and its synthetic conditions were optimized by using two ML techniques.
View Article and Find Full Text PDFThe thermodynamic (PCN-222) and kinetic (PCN-224) products of porphyrinic Zr-metal-organic frameworks (MOFs) were synthesized via an anodic dissolution approach for the first time. To the best of our knowledge, this is the first report of MOF polymorphs being controlled by electrolysis. The selective formation of PCN-222 requires an amorphous component to be present on the electrode during the initial reaction process.
View Article and Find Full Text PDFThe evaluation of angiogenesis inhibitors requires the analysis of the precise structure and function of tumor vessels. The anti-angiogenic agents lenvatinib and sorafenib are multi-target tyrosine kinase inhibitors that have been approved for the treatment of hepatocellular carcinoma (HCC). However, the different effects on tumor vasculature between lenvatinib and sorafenib are not well understood.
View Article and Find Full Text PDFThe technology to accurately image the morphology of tumor vessels with X-ray contrast agents is important to clarify mechanisms underlying tumor progression and evaluate the efficacy of chemotherapy. However, in clinical practice, iodine-based contrast agents present problems such as short blood retention owing to a high clearance ability and insufficient X-ray absorption capacity when compared with other high atomic number elements. To resolve these issues, gold nanoparticles (AuNPs), with a high atomic number, have attracted a great deal of attention as contrast agents for angiography, and have been employed in small animal models.
View Article and Find Full Text PDFSarcopenia is an age-related loss of skeletal muscle associated with adverse outcomes such as falls, fractures, disability, and increased mortality in older people and hospitalized patients. About half of older male nursing home residents have sarcopenia. The diagnostic criteria by the European Working Group on Sarcopenia in Older People (EWGSOP) and the Asian Working Group for Sarcopenia (AWGS) have led to increased interest in sarcopenia.
View Article and Find Full Text PDFWe developed adaptive optical (AO) two-photon excitation microscopy by introducing a spatial light modulator (SLM) in a commercially available microscopy system. For correcting optical aberrations caused by refractive index (RI) interfaces at a specimen's surface, spatial phase distributions of the incident excitation laser light were calculated using 3D coordination of the RI interface with a 3D ray-tracing method. Based on the calculation, we applied a 2D phase-shift distribution to a SLM and achieved the proper point spread function.
View Article and Find Full Text PDFCorrection for 'FRET-based intracellular investigation of nanoprodrugs toward highly efficient anticancer drug delivery' by Farsai Taemaitree et al., Nanoscale, 2020, 12, 16710-16715, DOI: 10.1039/D0NR04910G.
View Article and Find Full Text PDFIn order to overcome unpredictable side-effects and increased cytotoxicity of conventional carrier-based anticancer drug delivery systems, several systems that consist exclusively of the pure drug (or prodrug) have been proposed. The behavior and dynamics of these systems after entering cancer cells are, however, still unknown, hindering their progress towards in vivo and clinical applications. Here, we report a comprehensive in cellulo study of carrier-free SN-38 nanoprodrugs (NPDs), previously developed by our group.
View Article and Find Full Text PDFA fluorophore encapsulated in a metal-organic framework showed photochromic multicolour fluorescence. Irradiation with an ultraviolet laser induced the relocation of the fluorophore from a polar to a nonpolar environment, altering the emission from red to blue. This change in emission color can be repeatably recovered by heating the fluorophore-MOF composite.
View Article and Find Full Text PDFSilver nanowires have attracted considerable attention as subdiffraction limited diameter waveguides in a variety of applications including cell endoscopy and photonic integrated circuitry. Optical signal transport occurs by coupling light into propagating surface plasmons, which scatter back into light further along the wire. However, these interconversions only occur efficiently at wire ends, or at defects along the wire, which are not controlled during synthesis.
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