This work aimed to investigate and compare the composition and the physicochemical properties of 18 different sources of edible vegetable oils. A systematic study on the correlation between ...composition and physical properties was performed using Fourier Transform Infrared (FTIR) Spectroscopy and fatty acid chromatographic analysis. Principal component analysis of FTIR spectra is performed to classify edible oils concerning their physical properties. The results demonstrate the potentiality of the method associated with multivariate statistics analysis as powerful, fast, and non-destructive tools for characterization and quality control of edible vegetable oils.
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•The correlation of composition and physicochemical properties of edible vegetable oils•Chromatographic and spectroscopic techniques associated with multivariate statistics analysis•Unsaturated fatty acids are related to mass density, dynamic viscosity, oxidative stability index and refractive index.•These techniques allow predicting oil properties, helping in the characterization and quality control of vegetable oils.•Direct correlation of the PCA components with the set of information about composition and physical properties of the oils
Photoactivation of Erythrosine in simulated body fluids Bergmann, Eduardo V.; Capeloto, Otávio A.; Catanio, Angelo T.S. ...
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy,
10/2021, Letnik:
259
Journal Article
Recenzirano
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•Photoactivation process of Erythrosine was investigated in different simulated body fluids.•Optical techniques were used to investigate the photoactivation process.•Thermal lens ...results reveled photobleaching in submicromolar concentrations range.•Clear differences in the photodegradation kinetics, triplet lifetime and singlet oxygen generation were observed.•The results presented could help to explain and to define Photodynamic Therapy application protocols.
Photodynamic Therapy (PDT) is a powerful technique for the treatment of cancer and non-cancerous diseases. The precise PDT treatment protocol definition must consider the performance difference between in vitroand in vivoapplications. This also occurs in other biological studies, and to partially overcome this difficulty, the simulated body fluids are generally applied as a prior understanding of the particularities of the different systems. However, in PDT these studies are scarce. In this work, we investigated the photoactivation of Erythrosine, a photosensitizer widely used in PDT, in different simulated body fluids. Differences in the photodegradation kinetics, triplet lifetime, and singlet oxygen generation were observed. The results can help to explain and to define PDT application protocols.
In the last few years, experimental data of many different sources has been gathered to show that order parameter curves of essentially all nematic liquid crystals (NLCs) compounds can be reduced to ...a single and universal curve of the corresponding states; experimental data of an impressive number of different nematic compounds has been linearly rescaled in such a way that all them coalesced in a single curve. The surprising novelty observed on NLCs is that this universal behaviour is not restricted to the neighbourhoods of a critical region, as is usually expected from critical phenomena, but it covers the entire domain of the nematic phase, from the nematic isotropic temperature to the nematic crystalline temperature. The aim of this paper is to study the statistical mechanics fundamentals of this behaviour and show that it is a consequence of the universality of the angular part of the potential of the interaction between the particles composing the liquid crystal (LC). We will illustrate this behaviour presenting evidences that it can be found on the smectic-A phase.
In this work we show experimental results reporting the induced order in isotropic phase of a lyotropic liquid cxzrystal(KL/DeOH/water)when it is submitted to a mechanical vibration. We have been ...found five resonance frequencies for all isotropic domains surrounded by lamellar phases and two principal frequencies in both isotropic regions with nematic phase between them. In order to make a comparison with others isotropic fluids the optical transmittance of the lyotropic has been found of about four thousand when compared with DeOH and, at least three hundred in comparison to water. We are exploring this effect to produce a mechanical vibration sensor able to detect small mechanical perturbations at room temperature. As far we know this appears to be one of the first real technological application of a device based upon lyotropic liquid crystals.
