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Ultrafast time-resolved infrared (TRIR) is used to report on the binding site of the [Ru(phen) 2 (dppz)] 2+ "light-switch" complex with both bimolecular (Oxytricha nova telomere) and intramolecular (human telomere) guanine-quadruplex structures in both K + and Na + containing solutions. TRIR permits the simultaneous monitoring both of the "dark" and "bright" states of the complex and of the quadruplex nucleobase bases, the latter via a Stark effect induced by the excited state of the complex. These data are used to establish the contribution of guanine base stacking and loop interactions to the binding site of this biologically relevant DNA structure in solution. A particularly striking observation is the strong thymine signal observed for the Na + form of the human telomere sequence, which is expected to be in the anti-parallel conformation., (© 2020 Wiley-VCH GmbH.)

Ultrafast time resolved infrared (TRIR) is used to report on the binding site of the "light-switch" complex [Ru(phen) 2 (dppz)] 2+ 1 to i-motif structures in solution. Detailed information is provided due to perturbation of the local base vibrations by a 'Stark-like' effect which is used to establish the contribution of thymine base loop interactions to the binding site of 1 in this increasingly relevant DNA structure.

The controlled surface functionalisation of polystyrene beads (200 nm) with a lipoic acid derivative is used to assemble composites with between 4 to 20% loadings of citrate stabilised gold nanoparticles (13 nm-30 nm), which exhibit variable optical properties arising from interactions of the nanoparticle surface plasmon resonance (SPR). The decrease in average interparticle distance at higher loadings results in a red-shift in the SPR wavelength, which is well described by a universal ruler equation. The composite particles are shown to act as good SERS substrates for the standard analyte 4-mercaptophenol. The direct assessment of the SERS activity for individual composite particles solution is achieved by Raman optical tweezer measurements on 5.3 μm composite particles. These measurements show an increase in performance with increasing AuNP size. Importantly, the SERS activity of the individual particles compares well with the bulk measurements of samples deposited on a surface, indicating that the SERS activity arises primarily from the composite and not due to composite-composite interactions. In both studies the optimum SERS response is obtained with 30 nm AuNPs.

UV-generated excited states of cytosine (C) nucleobases are precursors to mutagenic photoproduct formation. The i-motif formed from C-rich sequences is known to exhibit high yields of long-lived excited states following UV absorption. Here the excited states of several i-motif structures have been characterized following 267 nm laser excitation using time-resolved infrared spectroscopy (TRIR). All structures possess a long-lived excited state of ∼300 ps and notably in some cases decays greater than 1 ns are observed. These unusually long-lived lifetimes are attributed to the interdigitated DNA structure which prevents direct base stacking overlap., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Carbon nanomaterials are among the most broadly discussed, researched and applied of synthetic nanomaterials. The structural diversity of these materials provides an array of unique electronic, magnetic and optical properties, which when combined with their robust chemistry and ease of manipulation, makes them attractive candidates for sensor applications. Furthermore, the biocompatibility exhibited by many carbon nanomaterials has seen them used as in vivo biosensors. Carbon nanotubes, graphene and carbon dots have come under intense scrutiny, as either discrete molecular-like sensors, or as components which can be integrated into devices. In this review we consider recent developments in the use of carbon nanoparticles and nanostructures as sensors and consider how they can be used to detect a diverse range of analytes.

The aim of this study was to comprehend the meaning of using illness narratives to raise awareness among nursing students and healthcare professionals toward the family-centred care model. The adopted methodological framework was Qualitative Content Analysis based on the philosophy of Family-Centered Care. Data were collected by means of assessments provided by 29 participants at an event in 2013, in São Paulo. The resulting analytical category was "transformed by the family narrative", which consisted of three sub-categories: Favours a better understanding of the family's experience; facilitates learning of family issues; and triggers thought on family-centered care. Results showed that hearing the family narrative on experiences with illness and hospitalization raises awareness among nursing students and healthcare professionals toward the family-centered care model, and facilitates learning of this model of care.

The study aimed to understand the experience of having a child hospitalized with Influenza A (H1N1). This qualitative study was conducted with five mothers of children living in Maringá-PR, hospitalized with this diagnosis, during the years 2009 and 2010. Data were collected in households, through semi-structured interviews and subjected to thematic content analysis. The diagnosis and the need for isolation caused great impact on families, triggering uncertainty about the future of children. Mothers indicated the lack of information related to the disease and isolation as a source of insecurity and, difficulties to follow the hospital routines and even in family relationships. There is need for nursing professionals to understand that this is a difficult time for the family, especially for the mother, being necessary to seek ways to minimize its effects. The bond and the provision of information can facilitate the process of hospitalization / isolation of the child.