The impact of doped silicon quantum dots on human osteoblasts

Abstract

Silicon (Si) nanostructures allow for the expansion of the application spectrum of this important semiconductor material with respect to the fields of optoelectronics and photonics. At the same time, the significant potential of Si quantum dots (SiQDs) has been revealed in terms of their potential application in the areas of biology and medicine due to their biocompatibility, low toxicity and natural biodegradability unlike currently used semiconductor quantum dots. As far as this study is concerned, SiQDs co-doped with boron and phosphorus were used for the in vitro evaluation of their cytotoxicity in human osteoblasts. Two chemically identical types of SiQD differing in terms of their size and photoluminescence (PL) were studied. They both display long-lasting dispersion in methanol and even in aqueous media as well as PL which is not sensitive either to changes in the environment or surface modifications. Our experiments revealed significant differences between the two types of SiQD tested with concern to their behavior in a cell culture environment depending on increasing concentration (25 -125 µg/ml) and cultivation conditions (the presence or absence of proteins from the fetal bovine serum -component of the cultivation medium). Detailed description of their optical parameters and the evaluation of zeta potential enhance the understanding of the complexities of the in vitro results obtained.

Doped and codoped silicon nanocrystals: The role of surfaces and interfaces

“…An advantage of this method concerns the possibility of producing highly dispersive Si-NCs in polar solvents or water solutions of different PH, without employing organic ligands, thus permitting the use of these Si-NCs for biomedical applications [49]. Figure 20 shows a picture of a methanol solution in which (c) PL spectra of codoped Si-NCs with different size, that is, grown at different temperatures.…”

“…[10] . 5 The possibility to exploit the size, shape and surface termination [30] of the Si-NCs togheter with their low toxicity and good biocompatibility has prompted their application in several broad fields such as microeletronics [2,31,32], photonics [33,34], non-linear optics [35,36,37], secure communications [36], photovoltaics, in the so-called third-generation solar cells, solar fuels [3,38,39,40,41,42,43], thermoelectrics [44,45] and biomedicine [46,47,48,49,50].…”

Single-dot spectroscopy of boron and phosphorus codoped silicon quantum dots

“…30 In vitro fluorescence imaging of cancer cells by codoped Si QDs has been recently demonstrated. 31 The size-dependence of the energy state structure of B and P codoped Si QDs has been studied by PL spectroscopy, 32 photoemission yield spectroscopy (PYS), 33 and valence band X-ray photoelectron spectroscopy (XPS). 33 These measurements reveal that the PL of codoped Si QDs arises from the transition between the donor to acceptor states in the bandgap, and the PL energy is several hundred meV lower than that of undoped Si QDs of a comparable size.…”

Immunomodulatory Potential of Differently-Terminated Ultra-Small Silicon Carbide Nanoparticles

“…Nevertheless, the effect induced by the SiC-based NPs on the various cells is apparent, thus indicating the existence of interaction. Moreover, other research has pointed out the potential for NP-cell interaction under such conditions [40][41][42]. The only exception where the ζ was shifted to a surface charge range that favored cluster formation involved the SiC-OH particles incubated in the RPMI 1640 medium.…”

“…The concentration gradient of the NPs used herein was based on our previous research on different types of ultra-small silicon-based NPs [42,44]. In both of these studies, said concentration gradients proved to have an impact on metabolic activity of osteoblastic cell line (SAOS-2).…”