RESUMEN
Boron nitride nanotubes (BNNTs) have unique physical properties, of value in biomedical applications; however, their dispersion and functionalization represent a critical challenge in their successful employment as biomaterials. In the present study, we report a process for the efficient disentanglement of BNNTs via a dual surfactant/polydopamine (PD) process. High-resolution transmission electron microscopy (HR-TEM) indicated that individual BNNTs become coated with a uniform PD nanocoating, which significantly enhanced dispersion of BNNTs in aqueous solutions. Furthermore, the cytocompatibility of PD-coated BNNTs was assessed in vitro with cultured human osteoblasts (HOBs) at concentrations of 1, 10, and 30 µg/mL and over three time-points (24, 48, and 72 h). In this study it was demonstrated that PD-functionalized BNNTs become individually localized within the cytoplasm by endosomal escape and that concentrations of up to 30 µg/mL of PD-BNNTs were cytocompatible in HOBs cells following 72 h of exposure.
Asunto(s)
Materiales Biocompatibles/farmacología , Compuestos de Boro/química , Indoles/química , Nanotubos/química , Polímeros/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacocinética , Compuestos de Boro/farmacocinética , Tampones (Química) , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Citoplasma/efectos de los fármacos , Citoplasma/metabolismo , Humanos , Indoles/farmacocinética , Microscopía Electrónica de Transmisión , Osteoblastos/efectos de los fármacos , Espectroscopía de Fotoelectrones , Polímeros/farmacocinética , Espectrometría por Rayos XRESUMEN
Single and double dearomatization of pyridine rings was observed in MnI complexes with an N2S2 pyridinophane ligand via deprotonation of one or two CH2 arms, respectively. In contrast to other N,S-donor pincer-like systems, the dearomatized (N2S2)Mn species were found to be stable, with the dearomatization being reversible.
RESUMEN
Rapid growth and expansion of engineered nanomaterials will occur when the technology can be used safely. Quantum dots have excellent prospects in clinical applications, but the issue of toxicity has not yet been resolved. To enable their medical implementation, the effect on, and mechanisms in, live cells should be clearly known and predicted. A massive amount of experimental data dedicated to nanotoxicity has been accumulated to-date, but it lacks a logical structure. The current challenge is to organize existing knowledge into lucid biological and mathematical models. In our review we aim to describe the interplay of various cell death mechanisms triggered by quantum dots as a consequence of particle parameters and experimental conditions.