Photo-responsive graphene and carbon nanotubes to control and tackle biological systems

Photo-responsive multifunctional nanomaterials are receiving considerable attention for biological applications because of their unique properties. The functionalization of the surface of carbon nanotubes (CNTs) and graphene, among other carbon based nanomaterials, with molecular switches that exhibit reversible transformations between two or more isomers in response to different kind of external stimuli, such as electromagnetic radiation, temperature and pH, has allowed the control of the optical and electrical properties of the nanomaterial. Light-controlled molecular switches, such as azobenzene and spiropyran, have attracted a lot of attention for nanomaterial's functionalization because of the remote modulation of their physicochemical properties using light stimulus. The enhanced properties of the hybrid materials obtained from the coupling of carbon based nanomaterials with light-responsive switches has enabled the fabrication of smart devices for various biological applications, including drug delivery, bioimaging and nanobiosensors. In this review, we highlight the properties of photo-responsive carbon nanomaterials obtained by the conjugation of CNTs and graphene with azobenzenes and spiropyrans molecules to investigate biological systems, devising possible future directions in the field

Toxicological profile of calcium carbonate nanoparticles for industrial applications.

Calcium carbonate nanoparticles (CaCO3NPs) derived from CO2 are promising materials for different industrial applications. It is imperative to understand their toxicological profile in biological systems as the human and environmental exposures to CaCO3NPs increases with growing production. Here, we analyse the cytotoxicity of CaCO3NPs synthesized from a CaO slurry on two cell lines, and in vivo on zebrafish (Danio Rerio). Our results demonstrate the CaCO3NPs in vitro safety as they do not cause cell death or genotoxicity. Moreover, zebrafish treated with CaCO3NPs develop without any abnormalities, confirming the safety and biocompatibility of this nanomaterial

The Utility of Zebrafish as a Model for Screening Developmental Neurotoxicity

The developing central nervous system and the blood brain barrier are especially vulnerable and sensitive to different chemicals, including environmental contaminants and drugs. Developmental exposure to these compounds has been involved in several neurological disorders, such as autism spectrum disorders as well as Alzheimer’s and Parkinson’s diseases. Zebrafish (Danio Rerio) have emerged as powerful toxicological model systems that can speed up chemical hazard assessment and can be used to extrapolate neurotoxic effects that chemicals have on humans. Zebrafish embryos and larvae are convenient for high-throughput screening of chemicals, due to their small size, low-cost, easy husbandry, and transparency. Additionally, zebrafish are homologous to other higher order vertebrates in terms of molecular signaling processes, genetic compositions, and tissue/organ structures as well as neurodevelopment. This mini review underlines the potential of the zebrafish as complementary models for developmental neurotoxicity screening of chemicals and describes the different endpoints utilized for such screening with some studies illustrating their use

Phenological growth and development stages of the native Patagonian fruit species Berberis buxifolia Lam

This work studied the phenological growth and development stages of Berberis buxifolia, a native Patagonian species, whose purple berries are of economic value. Data were recorded from a population of B. buxifolia adult plants, growing naturally near Ushuaia city, 54º 48´SL, 68º 19´WL (Tierra del Fuego, Argentina). The BBCH-scale has been adopted in this study, and the phenological stages were coded using two digits. Nine principal growth and development stages were recognized for the phenological description of B. buxifolia, starting with vegetative and mixed bud development (stage 0). The following four of them were assigned to the vegetative growth, which described leaf development on shoots (stage 1), shoot elongation (stage 3), development of plant propagation organs (stage 4) and partial senescence, beginning of dormancy (stage 9). The last four principal growth stages describe flower emergence (stage 5), flowering (stage 6), fruit development (stage 7) and maturity of fruit (stage 8).Fil: Arena, Miriam Elisabet. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Giordani, Edgardo. Universita Degli Studi Di Firenze; ItaliaFil: Radice, Silvia. Universidad de Moron. Facultad de Agronomia y Ciencias Agroalimentarias. Laboratorio de Investigaciones En Fisiologia Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Toxicity assessment of laser-induced graphene by zebrafish during development

Abstract Laser-induced graphene (LIG) is a three-dimensional porous graphene-based material easily prepared by single or multiple laser direct writing on a polymeric or organic surface. It possesses impressive physical and chemical properties, including high surface area, hierarchical porosity, and good electrical conductivity. Here, we investigate the toxicological profile of LIG and its impact in zebrafish (Danio rerio) as in vivo biological models with high homology with humans. We evaluate the effect of LIG, administered in different concentrations to zebrafish embryos, on different biological parameters, including embryo viability and morphological changes. Our results show that LIG does not exhibit toxic effects and does not interfere with zebrafish development, even at high concentrations. Our findings provide direct evidence of the LIG biocompatibility and offer a promising avenue for its safe use in biological applications

Flower development and pollen vitality of Moringa oleifera Lam. grown in a humid temperate climatic condition

Moringa oleifera is a tropical tree cultivated in many countries. This species has acquired a great importance in human nutrition and it was recently indicated as a “novel food” by the European Commission. Recently, moringa plants have been introduced in humid temperate climatic areas, among which Moreno (Buenos Aires Province - Argentina). In such area, the cultivation is possible for the production of leaves, but plants need protection during winter time in order to overcome damages due to low temperatures and hence to produce capsules and seeds. The main objective of this research was to study flower morphology and anatomy of M. oleifera, as well as microsporogenesis and viability of pollen grains of plants cultivated in Moreno in comparison with those produced in a humid sub-tropical climatic area of Argentina (San Miguel de Tucumán). Flowers grown in the temperate environment resulted similar for morphological parameters to those observed in the sub-tropical environment. Nevertheless, pollen grain fertility depended directly on air temperature and it was negatively affected by the lower temperatures registered in the temperate site. According to the observed results, pollen viability increases with mean monthly temperatures above 16°C