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1.
Biomater Sci ; 8(1): 39-63, 2019 Dec 17.
Article in English | MEDLINE | ID: mdl-31799977

ABSTRACT

The term secretome, which traditionally strictly refers to single proteins, should be expanded to also include the great variety of nanoparticles secreted by cells (secNPs) into the extracellular space, which ranges from high-density lipoproteins of a few nanometers to extracellular vesicles and fat globules of hundreds of nanometers. Widening the definition is urged by the ever-increasing understanding of the role of secNPs as regulators/mediators of key physiological and pathological processes, which also puts them in the running as breakthrough cell-free therapeutics and diagnostics. "Made by cells for cells", secNPs are envisioned as a sweeping paradigm shift in nanomedicine, promising to overcome the limitations of synthetic nanoparticles by unsurpassed circulation and targeting abilities, precision and sustainability. From a longer/wider perspective, advanced manipulation would possibly make secNPs available as building blocks for future "biogenic" nanotechnology. However, the current knowledge is fragmented and sectorial (the majority of the studies being focused on a specific biological and/or medical aspect of a given secNP class or subclass), the understanding of the nanoscale and interfacial properties is limited and the development of bioprocesses and regulatory initiatives is in the early days. We believe that new multidisciplinary competencies and synergistic efforts need to be attracted and augmented to move forward. This review will contribute to the effort by attempting for the first time to rationally gather and elaborate secNPs and their traits into a unique concise framework - from biogenesis to colloidal properties, engineering and clinical translation - disclosing the overall view and easing comparative analysis and future exploitation.


Subject(s)
Extracellular Vesicles/metabolism , Lipoproteins/metabolism , Nanoparticles/metabolism , Animals , Extracellular Vesicles/chemistry , Humans , Lipoproteins/chemistry , Molecular Conformation , Nanomedicine , Nanoparticles/chemistry
2.
Nanoscale ; 9(25): 8639-8646, 2017 Jun 29.
Article in English | MEDLINE | ID: mdl-28608884

ABSTRACT

Binder and effector molecules that allow studying and manipulating epigenetic processes are of biological relevance and pose severe technical challenges. We report the first example of a synthetic receptor able to recognize mono-methylated lysines in a histone H3 tail peptide, which has relevant functions in epigenetic regulation. Recognition is robust and specific regardless of the position and the number of mono-methylated lysines along the polypeptide chain. The peptide is first captured in solution by a tetraphosphonate cavitand (Tiiii) that selectively binds its Lys-NMe+ moieties. Separation from solution and detection of the peptide-Tiiii complexes is then enabled in one single step by an all dielectric SiO2-TiO2 core-shell resonator (T-rex), which captures the complex and operates fully reproducible signal transduction by non-plasmonic surface enhanced Raman scattering (SERS) without degrading the complex. The realized abiotic probe is able to distinguish multiple mono-methylated peptides from the single mono-methylated ones.

3.
J Environ Manage ; 159: 128-134, 2015 Aug 15.
Article in English | MEDLINE | ID: mdl-26063517

ABSTRACT

The Stabilization of heavy metals from municipal solid waste incineration (MSWI) fly ash by rice husk ash (RHA) is under intense study as an effective strategy to recover and reuse industrial and agricultural waste together. We compare the metal entrapment performances of RHA from different Asian rice sources ­ namely from Japonica rice grown in Italy and Indica rice grown in India ­ Physicochemical and morphological characterization of the final stabilized material show that the same thermal treatment may result in marked structural differences in the silica contained in the two RHA. Remarkably, one of them displays a crystalline silica content, although obtained by a thermal treatment below 800 °C. We also find that the presence of an alkali metal ion (potassium) in the rice husk plays a crucial role in the attainment of the final silica phase. These physicochemical differences are mirrored by different stabilization yields by the two RHA.


Subject(s)
Coal Ash/chemistry , Incineration/methods , Metals, Heavy/chemistry , Oryza , Solid Waste , Coal Ash/analysis , Metals, Heavy/analysis , Potassium/chemistry , Silicon Dioxide/chemistry , Temperature
4.
J Nanosci Nanotechnol ; 9(2): 1164-8, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19441479

ABSTRACT

A flow type quartz crystal microbalance (QCM) (bio)chemical sensor was developed for the real time determination of heavy metal ions that is suitable for environmental monitoring. A new process has been developed which enables to obtain surface-modified gold electrodes with high heavy metal ions complexing ability. The sensing performances of the piezoelectric sensor used in a flow-through setup were investigated by monitoring the frequency variation induced by the presence of heavy metal ions, such as copper and lead, as model ions, in aqueous media. X-Ray Reflectivity (XRR) and Atomic Force Microscopy (AFM) were carried out to characterize the unmodified and modified gold surfaces.

5.
J Phys Chem B ; 110(51): 25740-5, 2006 Dec 28.
Article in English | MEDLINE | ID: mdl-17181215

ABSTRACT

In potassium niobiosilicate (KNS) glasses, nanostructuring can be driven and controlled by thermal treatments at the glass transition temperature and/or by modulation of the chemical composition. The tight relationship between nanostructure and nonlinear optical properties suggests these bulk nanomaterials as an appealing route to nanophotonics. The focus of this paper is placed on assessing the phase transformations which occur in these materials upon annealing at the glass transition temperature and subsequent heating. High-temperature resolved X-ray diffraction (HTXRD) and high-resolution transmission electron microscopy (HRTEM) experiments are integrated with previously published results for in-depth insight. It will be shown that nanostructuring evolves from nucleation of niobium-rich nanocrystals, which are up to 20 nm large, uniformly distributed in the matrix bulk, and metastable. Formation kinetics as well as phase transformation of the nanocrystals are determined by the glass composition. Depending on it, nanocrystal nucleation can be preceded or not by phase separation, and the nanocrystals' phase transition can be of first or second order.

6.
J Phys Chem B ; 109(2): 711-5, 2005 Jan 20.
Article in English | MEDLINE | ID: mdl-16866431

ABSTRACT

In this paper the solid-state transformations under heating of cis-[Ir(CO)2Cl(C5H5N)] are discussed. The complexity of the transformations was revealed by integrating infrared spectroscopy, conventional and bidimensional X-ray diffraction, thermal analysis, and hot stage optical microscopy. During heating anisotropic expansion of the lattice along the Ir-Ir stacking takes place. Then cis-[Ir(CO)2Cl(C5H5N)] undergoes an irreversible solid-solid phase transition to a lattice of higher symmetry followed by a reversible transition into the amorphous phase. Under proper cooling a partial recrystallization takes place. Experiments in the presence of oxygen must be carried out in short time periods to avoid oxidation from Ir(I) to Ir(III).


Subject(s)
Iridium/chemistry , Optics and Photonics , Organometallic Compounds/chemistry , Temperature , Crystallization , Electrons
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