Papers by Alessandra Pinna
The present doctoral thesis focuses on the antioxidant activity of cerium oxide nanostructured ma... more The present doctoral thesis focuses on the antioxidant activity of cerium oxide nanostructured materials (nanoceria) in biological systems. This goal is obtained through an interdisciplinary approaches spanning from chemistry and physics to biology and medicine. Nanoceria is studied in form of nanoparticles both naked and integrated nanocomposites films. The physicochemical properties are studied by a complete set of characterization techniques such as XRD, FTIR and Raman spectroscopies, DLS, AFM, μ-XRF, SEM and TEM. A specific emphasis is placed on the interactions with cells (PC12, PBMC, oocyte and spermatozoa) as a function of the nanoceria concentration. Different techniques for cell analysis, such as flow cytometry and confocal microscopy, allow monitoring the fate and viability of nanoparticles into the cells. Our results show that nanoceria can be successfully used as antioxidant agent in biomedical field to improve the cells viability both in physiological condition (IVM) an...
Journal of Synchrotron Radiation, 2016
Hard X-rays, deriving from a synchrotron light source, have been used as an effective tool for pr... more Hard X-rays, deriving from a synchrotron light source, have been used as an effective tool for processing hybrid organic–inorganic films and thick coatings up to several micrometres. These coatings could be directly modified, in terms of composition and properties, by controlled exposure to X-rays. The physico-chemical properties of the coatings, such as hardness, refractive index and fluorescence, can be properly tuned using the interaction of hard X-rays with the sol–gel hybrid films. The changes in the microstructure have been correlated especially with the modification of the optical and the mechanical properties. A relationship between the degradation rate of the organic groups and the rise of fluorescence from the hybrid material has been observed; nanoindentation analysis of the coatings as a function of the X-ray doses has shown a not linear dependence between thickness and film hardness.
PLOS ONE, 2020
Malaria represents one of the most common infectious diseases which becoming an impellent public ... more Malaria represents one of the most common infectious diseases which becoming an impellent public health problem worldwide. Antimalarial classical medications include quininebased drugs, like chloroquine, and artesunate, a derivative of artemisinin, a molecule found in the plant Artemisia annua. Such therapeutics are very effective but show heavy side effects like drug resistance. In this study, "green" silver nanoparticles (AgNPs) have been prepared from two Artemisia species (A. abrotanum and A. arborescens), traditionally used in folk medicine as a remedy for different conditions, and their potential antimalarial efficacy have been assessed. AgNPs have been characterized by UV-Vis, dynamic light scattering and zeta potential, FTIR, XRD, TEM and EDX. The structural characterization has demonstrated the spheroidal shape of nanoparticles and dimensions under 50 nm, useful for biomedical studies. Zeta potential analysis have shown the stability and dispersion of green AgNPs in aqueous medium without aggregation. AgNPs hemocompatibility and antimalarial activity have been studied in Plasmodium falciparum cultures in in vitro experiments. The antiplasmodial effect has been assessed using increasing doses of AgNPs (0.6 to 7.5 μg/ mL) on parasitized red blood cells (pRBCs). Obtained data showed that the hemocompatibility of AgNPs is related to their synthetic route and depends on the administered dose. A. abrotanum-AgNPs (1) have shown the lowest percentage of hemolytic activity on pRBCs, underlining their hemocompatibility. These results are in accordance with the lower levels of parasitemia observed after A. abrotanum-AgNPs (1) treatment respect to A. arborescens-AgNPs (2), and AgNPs (3) derived from a classical chemical synthesis. Moreover, after 24 and 48 hours of A. abrotanum-AgNPs (1) treatment, the parasite growth was locked in the ring stage, evidencing the effect of these nanoparticles to hinder the maturation of P. falciparum. The anti-malarial activity of A. abrotanum-AgNPs (1) on pRBCs was demonstrated to be higher than that of A. arborescens-AgNPs (2).
Acta Biomaterialia, 2021
Osteoporosis, a chronic metabolic bone disease, is the most common cause of fractures. Drugs for ... more Osteoporosis, a chronic metabolic bone disease, is the most common cause of fractures. Drugs for treating osteoporosis generally inhibit osteoclast (OC) activity, but are rarely aimed at encouraging new bone growth and often cause severe systemic side effects. Reactive oxygen species (ROS) are one of the key triggers of osteoporosis, by inducing osteoblasts (OBs) and osteocyte apoptosis and promoting osteoclastogenesis. Here we tested the capability of the ROS-scavenger nanoceria encapsulated within mesoporous silica nanoparticles (Ce@MSNs) to treat osteoporosis using a pre-osteoblast MC3T3-E1 cell monoculture in stressed and normal conditions. Ce@MSNs (diameter of 80 ± 10 nm) were synthesised following a scalable two-step process involving sol-gel and wet impregnation methods. The Ce@MSNs at concentration of 100 μg mL-1 induced a significant reduction in oxidative stress produced by t-butyl hydroperoxide and did not alter cell viability significantly. Confocal microscopy showed that MSNs and Ce@MSN were internalised into the cytoplasm of the pre-osteoblasts after 24 h but not in the nucleus, avoiding any DNA and RNA modifications. Ce@MSNs provoked mineralisation of the pre-osteoablasts without osteogenic supplements, which did not occur when the cells were exposed to MSN without nanoceria. In a co-culture system of MC3T3-E1 and RAW264.7 macrophages, the Ce@MSNs exhibited antioxidant capability and stimulated cell proliferation and osteogenic responses without adding osteogenic supplements to the culture. The work brings forward an effective platform based for facile synthesis of Ce@MSNs to interact with both OBs and OCs for treatment of osteoporosis.
Science of The Total Environment, 2020
• PM mass collection for toxicological studies in various microenvironments is reviewed. • Lower ... more • PM mass collection for toxicological studies in various microenvironments is reviewed. • Lower amounts of PM mass limit the workflows for toxicity assessments. • Portable samplers with high flow rates are suitable for both indoor and outdoor measurement. • Cyclone sampling technique effectively collects viruses in all environments. • Predictive modelling aids in identifying hotspots for particle mass collection.
RSC Advances, 2018
Pinna and co-workers report the design of a MOF-based magnetic composite for long-term release of... more Pinna and co-workers report the design of a MOF-based magnetic composite for long-term release of dopamine in the PC12 cell line.
Reproductive biology and endocrinology : RB&E, Jan 6, 2018
Cerium oxide nanoparticles (CeO NPs) are able to store and release oxygen, conferring them scaven... more Cerium oxide nanoparticles (CeO NPs) are able to store and release oxygen, conferring them scavenger activity against oxidative stress. However, their effects in reproductive systems are not yet well understood. The aim of the study was to investigate the effects of exposure of refrigerated ram semen to CeO NPs for 96 h on the main structural and kinematic parameters of spermatozoa. The ejaculates of 5 Sarda rams were collected, pooled and diluted in a soybean lecithin extender. Samples were exposed to increasing doses of CeO NPs (0, 44 and 220 μg/mL) and stored at 4 °C for 96 h. Analyses of kinematic parameters (computer assisted sperm analysis, CASA), integrity of membranes (PI/PSA staining), ROS production (HDCFDA staining) and DNA damage (sperm chromatin structure assay with acridine orange, SCSA) were performed every 24 h (0, 24, 48, 72 and 96 h of incubation). The experiment was carried out in 6 replicates. Data were analysed by repeated measures ANOVA with Bonferroni's as...
Journal of Sol-Gel Science and Technology, 2016
The controlled growth of Ag nanoparticles into graphene-TiO 2 mesoporous films has been triggered... more The controlled growth of Ag nanoparticles into graphene-TiO 2 mesoporous films has been triggered by hard X-ray exposure provided by a synchrotron storage ring. The kinetic process has been studied by UV-visible spectroscopy as a function of the X-ray dose and compared to the nanoparticle growth induced in a bare mesoporous titania matrix. The graphene layers act as a preferential nucleation sites, allowing a faster nucleation of the nanoparticles. Moreover, the growth of larger nanoparticles is also promoted as a function of the exposure dose. The combined bottom-up and top-down approach to fabricate nanocomposites porous films embedding both graphene and plasmonic nanoparticles is expected to be a fundamental tool for the design of new analytical platforms based on the enhancement of the Raman signals.
Acta biomaterialia, Jul 27, 2017
A challenge in using bioactive melt-derived glass in bone regeneration is to produce scaffolds wi... more A challenge in using bioactive melt-derived glass in bone regeneration is to produce scaffolds with interconnected pores while maintaining the amorphous nature of the glass and its associated bioactivity. Here we introduce a method for creating porous melt-derived bioactive glass foam scaffolds with low silica content and report in vitro and preliminary in vivo data. The gel-cast foaming process was adapted, employing temperature controlled gelation of gelatin, rather than the in situ acrylic polymerisation used previously. To form a 3D construct from melt derived glasses, particles must be fused via thermal processing, termed sintering. The original Bioglass® 45S5 composition crystallises upon sintering, altering its bioactivity, due to the temperature difference between the glass transition temperature and the crystallisation onset being small. Here, we optimised and compared scaffolds from three glass compositions, ICIE16, PSrBG and 13-93, which were selected due to their widened...
Theriogenology, 2016
The aim of the study was to investigate the interaction and the short-term effects of increasing ... more The aim of the study was to investigate the interaction and the short-term effects of increasing doses of CeO 2 NPs on ram spermatozoa, stored at 4°C for up to 24h, on the main functional and kinematic parameters. Spermatozoa were incubated with 0, 22, 44 and 220 µg/mL of CeO 2 NPs at 4°C and submitted at 0, 2 and 24h to the following analyses: i) intra-cellular uptake of CeO 2 NPs by the spermatozoa; ii) kinematic parameters; iii) acrosome and membrane integrity; iv) integrity of DNA; v) mitochondrial activity; 3) ROS production. The results indicated that the exposure of spermatozoa to increasing doses of nanoceria was well tolerated. No intracellular uptake of NPs by the cells was observed and both kinematic parameters and status of the membranes were not affected by the incubation with NPs (P>0.05). Moreover, no influence on the redox status of spermatozoa and on the levels of fragmentation of DNA was reported among groups at any time (P>0.05). The data collected provide new information about the impact of CeO 2 NPs on the male gamete in large animal model and could open future perspectives about their biomedical use in the assisted reproductive techniques.
RSC Advances, 2015
Ceria nanoparticles with controlled size have been studied as antioxidant agents for the in vitro... more Ceria nanoparticles with controlled size have been studied as antioxidant agents for the in vitro protection of catecholaminergic cells (PC12) exposed to manganese, which is responsible for an occupational form of Parkinson-like disease.
Materials and Manufacturing Processes, 2015
ABSTRACT
Science of Advanced Materials, 2014
Among the myriad microfabrication approaches, Deep X-ray Lithography (DXRL) takes advantage of th... more Among the myriad microfabrication approaches, Deep X-ray Lithography (DXRL) takes advantage of the high penetration depth of hard X-rays. For the first time, this feature has been exploited for the precise control of surface chemical functionalities on a thick porous ceramic material. As a proof of concept, porous alumina membranes with controlled thickness (50 µ m) have been chosen to test the potential of DXRL. The Al 2 O 3 membranes were decorated with fluoro- and amino-silanes. These functionalized ceramic membranes were exposed to hard X-rays in a synchrotron facility, which allowed for the selective decomposition of the chemical functionalities in controlled areas. The water contact angle of hydrophobic-functionalized samples was measured to confirm the decomposition of the fluoro-silane in the exposed area, and water diffusion through the 200 nm pores of the alumina membranes was observed to occur only in the exposed area. The patterned amino-functionalized Al 2 O 3 samples were tested with an alcoholic solution containing Au cations, where it was found that gold nanoparticles only formed in the unexposed areas, whereas the amino functionality survived the radiation damage induced by the X-rays.
Journal of Nanoparticle Research, 2014
Superparamagnetic iron oxide nanoparticles of magnetite have been grafted on the surface of a hyb... more Superparamagnetic iron oxide nanoparticles of magnetite have been grafted on the surface of a hybrid organic-inorganic film prepared using an organically modified alkoxide, 3-glycidoxypropyltrimethoxysilane, as precursor. A solventless synthesis of the hybrid films at high pH has been employed and the surface chemistry of the deposited films has been processed by controlling the aging time of the sol. The films have been characterized by FTIR, Raman and UV spectroscopy and grazing incidence X-ray diffraction. Films prepared with fresh sols have shown a mixed presence of epoxides and hydroxyls on the surface, which enabled the successful grafting of the iron oxide nanoparticles. Films from aged sols, which contain only hydroxyls, have failed to bind the iron particles but have instead shown the capability of grafting ceria nanoparticles. This method has, therefore, allowed a direct grafting of nanoparticles on the hybrid surface without any post-synthetic functionalization step. Moreover, the phase transition induced in iron oxide nanoparticles by means of a laser beam has been exploited to pattern the film surface creating different domains of magnetite and hematite.
New Journal of Chemistry, 2014
Graphene–silica films with high optical transparency have been obtained by adding a dispersion of... more Graphene–silica films with high optical transparency have been obtained by adding a dispersion of exfoliated graphene into a silica sol.
The Journal of Physical Chemistry C, 2014
The possibility of extending the technological applications of photocatalytic mesoporous titania ... more The possibility of extending the technological applications of photocatalytic mesoporous titania films relies upon the capability of lowering the processing temperature while maintaining its functional properties. Here we present a synthesis of mesoporous titania films, which makes use of a partially fluorinated surfactant Zonyl FS300 as a mesostructuring agent. The photoinduced degradation activity has been followed by FTIR spectroscopy as a function of the films’ thermal annealing, ranging from 150 up to 400 °C, by using stearic acid as a model compound. The results have been compared with the benchmark templating agent Pluronic F127 and highlighted a constantly higher activity of the Zonyl-templated films, up to 50%, throughout the range of the temperatures analyzed. Raman spectroscopy indicates that Zonyl FS300 is capable of producing nanosized titania crystals at temperatures lower than Pluronic F127. This explains the different photocatalytic response of the corresponding mesoporous thin films proce...
New Journal of Chemistry, 2014
The tuning of epoxide opening in GPTMS films allows for smart tailoring of the surface chemistry.
New Journal of Chemistry, 2013
Materials Science and Engineering: C, 2021
The cellular response of murine primary macrophages to monodisperse strontium containing bioactiv... more The cellular response of murine primary macrophages to monodisperse strontium containing bioactive glass nanoparticles (SrBGNPs), with diameters of 90 ± 10 nm and a composition (mol%) of 88.8 SiO2-1.8CaO-9.4SrO (9.4% Sr-BGNPs) was investigated for the first time. Macrophage response is critical as applications of bioactive nanoparticles will involve the nanoparticles circulating in the blood stream and macrophages will be the first cells to encounter the particles, as part of inflammatory response mechanisms. Macrophage viability and total DNA measurements were not decreased by particle concentrations of up to 250 μg/mL. The Sr-BGNPs were actively internalised by the macrophages via formation of endosome/lysosome-like vesicles bordered by a membrane inside the cells. The Sr-BGNPs degraded inside the cells, with the Ca and Sr maintained inside the silica network. When RAW264.7 cells were incubated with Sr-BGNPs, the cells were polarised towards the pro-regenerative M2 population rather than the pro-inflammatory M1 population. Sr-BGNPs are potential biocompatible vehicles for therapeutic cation delivery for applications in bone regeneration.
Science of Advanced Materials, 2014
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Papers by Alessandra Pinna