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Confocal Raman microspectroscopy (CRM) with 633- and 785-nm excitation wavelengths combined with optical clearing (OC) technique was used for ex-vivo study of porcine skin in the Raman fingerprint region. The optical clearing has been performed on the skin samples by applying a mixture of glycerol and distilled water and a mixture of glycerol, distilled water and chemical penetration enhancer dimethyl sulfoxide (DMSO) during 30min and 60min of treatment. It was shown that the combined use of the optical clearing technique and CRM at 633nm allowed one to preserve the high probing depth, signal-to-noise ratio and spectral resolution simultaneously. Comparing the effect of different optical clearing agents on porcine skin showed that an optical clearing agent containing chemical penetration enhancer provides higher optical clearing efficiency. Also, an increase in treatment time allows to improve the optical clearing efficiency of both optical clearing agents. As a result of optical clearing, the detection of the amide-III spectral region indicating well-distinguishable structural differences between the type-I and type-IV collagens has been improved.

Recent studies have demonstrated that topical application of glycerol on intact skin does not affect its optical scattering properties. Investigators from our research group recently revisited the use of dimethyl sulfoxide (DMSO) as an agent with optical clearing potential. We address the use of optical clearing to enhance quantitation of subsurface fluorescence emission. We employed both in vitro and in vivo model systems to study the effect of topical DMSO application on fluorescence emission. Our in vitro experiments performed on a tissue-simulating phantom suggest that DMSO-mediated optical clearing enables enhanced characterization of subsurface fluorophores. With topical DMSO application, a marked increase in fluorescence emission was observed. After 30 min, the fluorescence signal at the DMSO-treated site was 9× greater than the contralateral saline-treated site. This ratio increased to 13× at 105 min after agent application. In summary, DMSO is an effective optical clearing agent for improved fluorescence emission quantitation and warrants further study in preclinical in vivo studies. Based on outcomes from previous clinical studies on the toxicity profile of DMSO, we postulate that clinical application of DMSO as an optical clearing agent, can be performed safely, although further study is warranted.

In this study, we evaluated the renal protective effects of a Chinese herbal preparation WH30⁺ in male Wistar rats with glycerol-induced acute renal failure and adenine-induced chronic renal failure. WH30⁺ is a Chinese herb preparation composed of Rheum Palmatum, Salvia Miltiorrhiza, Cordyceps Sinensis, Leonurus Sibiricus, Epihedium Macranthum, Radix Astragali, and Radix Codonopsis Pilosulae, which has been used to treat kidney deficiency in human. An acute renal failure and chronic renal failure rat model were introduced by glycerol injection (i.m.) and fed with adenine-excessive diet, respectively. WH30⁺ was administered to rats at the dose of 50 mg/kg/day from 10 days before the diseases were induced until the rats were sacrificed. A reduction in body weight (p < 0.01) was observed in rats with chronic renal failure, but there was no difference between treatment groups. However, the body weight of rats with acute renal failure without treatment was significantly lower than those treated with WH30⁺ (p < 0.05). Overall, serum creatinine and urea nitrogen were elevated significantly (p < 0.01) in renal failure rats compared to control. Treatment with WH30⁺ improved both serum creatinine and urea nitrogen slightly in both models. The WH30⁺-treated rats with acute renal failure had significantly (p < 0.05) greater creatinine clearance than those without treatment. The results of the study show that WH30⁺ is more effective in the prevention of acute renal failure than chronic renal failure.

Laser Speckle Contrast Imaging (LSCI) plays an important role in studying blood flow, but suffers from limited penetration depth of light in turbid tissue. The strong scattering of tissue obviously reduces the image contrast which decreases the sensitivity to flow velocity. Some image processing or optical clearing methods have been proposed to lessen the deficiency, but quantitative assessment of improvement is seldom given. In this study, LSCI was applied to monitor the blood flow through a capillary embedded within various tissue phantoms at depths of 0.25, 0.45, 0.65, 0.85 and 1.05 mm, and the flow velocity in capillary was controllable from 0 to 4 mm/s. Here, glycerol, a common optical clearing agent, was mixed with Intralipid at different volume ratio to make the reduced scattering coefficient of tissue phantom decrease from 13.00 to 0.50 cm^-1. The quantitative analysis demonstrates that the optical clearing method can obviously enhance the image contrast, imaging depth, and sensitivity to blood flow velocity. Comparing the Laser Speckle Contrast Analysis methods and the optical clearing method, we find that for typical turbid tissue, the sensitivity to velocity estimated by the Laser Speckle Temporal Contrast Analysis (LSTCA) is twice of that by the Laser Speckle Spatial Contrast Analysis (LSSCA); while the sensitivity to velocity estimated by using the two analysis methods has a 10-fold increase, respectively, if addition of glycerol makes the reduced scattering coefficient of tissue phantom decrease by 30%. Combining the LSTCA and the optical clearing method, the sensitivity to flow velocity will be further enhanced.

The development of electrocatalysts with high activity is essential to convbar glycerol into value-added chemicals through electrocatalytic oxidation. Nano-sized metals with prickly structures are expected to possess high electrocatalytic activity due to the strong electric field at the sharp tips. We propose a facile approach to prepare Au nanoparticles with prickly structure by galvanic displacement in this work. The reaction between Au³⁺ and Ni generates in situ highly dispersed Au nanoparticles with prickly structures on the Ni foam. Owing to appropriate prickly structure, the Au nanoparticles prepared at 25^∘C for 30 s exhibited the best electrocatalytic performance. Finite element simulation method simulations show that the high-density of positive charge at the tips forms strong electric field, which enriches OH⁻ ions and promotes glycerol oxidation, thus exhibiting excellent electrocatalytic activity. This study will guide further design/development of electrocatalytic nanostructured Au particles and provide an effective route to electrocatalytically oxidize glycerol.

This study is a pilot investigation on the effect of using nanosilica for reinforcing thermoplastic starch-based bioplastic films. An arbitrary 0.2wt.% of nanosilica particles were used to reinforce starch derived bioplastic materials and were further investigated for potential benefits. Nanosilica was extracted from rice husk and was characterized using methods like Fourier transform infrared spectroscopy (FTIR) technique and Brunauer–Emmett–Teller (BET) method. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques were used to determine the structure of nanosilica crystals. Scanning electron microscopy (SEM) technique was used to study the surface topography and composition of nano ‘silica. Both raw and reinforced bioplastic films were tested for thermal stability using thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) tests and their performance was compared. Mechanical properties were compared using tensile and tear tests and biodegradability was assessed through enzymatic degradation analysis. It was found that the presence of nanosilica improved the bonding of polymer matrix and in turn increased the thermal stability and tear strength. Nanosilica reinforced matrix resulted in the increase of surface area than raw bioplastic matrix, which lead to high rate of enzymatic reactivity and degradation rate.

A series of activated carbon (AC) supported Au nanocatalysts with different loadings of Au were prepared by using the homogeneous deposition–precipitation (HDP) method. The samples were characterised with myriad techniques such as X-ray diffraction (XRD), CO-chemisorption, N₂ adsorption–desorption measurements, transmission electron microscopy (TEM), inductively coupled plasma-optical emission spectrometer (ICP-OES) and X-ray photoelectron spectroscopy (XPS) to understand the structural and textural properties in detail. The catalysts were tested for the vapour phase oxidation of glycerol to glyceric acid under base-free medium in an aerobic condition at normal atmospheric pressure. The Au/AC nanocatalysts with smaller size Au particles ($<6$nm) showed higher glycerol conversion and selectivity for glyceric acid, and also a longer catalyst life. While the larger Au particles ($>10$nm) showed less activity and selectivity. Among all the nanocatalysts tested, the 1.0wt.% Au/AC sample having smaller particle size of Au showed the best catalytic performance in terms of glycerol conversion and glyceric acid selectivity. These results suggest that the oxidation activities of Au/AC nanocatalysts are strongly influenced by the size of Au nanoparticle, nature of the support material and through a metal-support interaction.

Currently, electrochemical anodizing is one of the most common processes in materials science, since, under the right conditions, it allows to modify the material surface without damaging it by means of redox reactions, generating an oxide layer that protects the material and improves its properties. In this paper, grade 2 titanium was anodized using a solution of hydrochloric acid, glycerol, and deionized water as electrolyte, and 0.5 M K₂CrO₄ as doping agent, with a voltage of 30 V for 4.5 h. After anodizing with and without chromium, annealing was performed at different temperatures (500${}^{\circ }$C, 600${}^{\circ }$C and 700${}^{\circ }$C) to promote structural and microhardness changes. The samples were analyzed by FE-SEM observing that the formation of nanostructures changes according to the heat treatment, where samples at 700${}^{\circ }$C with chromium begin to form nanorods and, compared to those without chromium, the nanorods are longer. The presence of Cr in anodized TiO₂ at different temperatures was confirmed by EDS technique. Using XRD, the microstructure of TiO₂ anodized with and without Cr was analyzed and anatase and rutile phases were found, with greater presence of anatase for samples with Cr. Finally, a maximum hardness of up to 10.27 GPa was obtained from the sample at 700${}^{\circ }$C without chromium, which is higher compared to the values of coatings with Cr. However, the anatase phase could be stabilized at higher temperatures making it suitable for medical applications since the anatase phase is the most biocompatible.

The design of a dendrimeric-like diglycerol-tetrasubstituted Zn(II) phthalocyanine resulted in a remarkably water-soluble compound due to the presence of 16 hydroxyls. Several parameters relevant to evaluate the photodynamic efficiency of a potentiel photosensitizer such as: aggregation behavior, fluorescence properties, singlet oxygen generation, binding to a carrier protein model (Bovine Serum Albumin) and partition coefficient have been measured. Biocompatibility was demonstrated by dark cytotoxicity in in vitro experiments. The absence of phototoxicity can be explained by an elevated hydrophilicity. All the collected data have confirmed that this new substitution pattern is promising to be used on phthalocyanines aiming at being photodynamic therapy agents.

Nowadays tools based on Scanning Probe Methods (SPM) have become indispensable in a wide range of applications such as cell imaging and spectroscopy, profilometry, or surface patterning on a nanometric scale. Common to all SPM techniques is a typically slow working speed which is one of their main drawbacks. The SPM speed barrier can be improved by operating a number of probes in parallel mode. A key element when developing probe array devices is a convenient read-out system for measurements of the probe deflection. Such a read-out should be sufficiently sensitive, resistant to the working environment, and compatible with the operation of large number of probes working in parallel. In terms of fabrication, the geometrical uniformity i.e. the realisation of large numbers of identical probes, is a major concern but also the material choice compatible with high sensitivity, the detection scheme and the working environment is a challenging issue. Examples of promising applications using parallel SPM are dip-pen-nanolithography, data storage, and parallel imaging.

The first dehydration of protonated glycerol taking place at its secondary site was investigated by density functional calculations by considering different conformations of glycerol. Five parallel reaction pathways via different conformers of protonated glycerol were found. One of these pathways leads to a direct formation of protonated 3-hydroxylpropanal (HPA), another one of these pathways produces protonated glycidol, and the other three produce protonated 3-hydroxy-1,1-propanediol (HPD). One of these pathways producing protonated HPD was found to have obviously larger relative reaction rate than other pathways. The dehydration of protonated HPD to afford protonate HPA requires a rather low reaction barrier (12 kcal/mol). These results show that the production of HPA via a stepwise process with protonated HPD as a key intermediate, is energetically favorable than via a one-step concerted process producing HPA.

The conversion of glycerol to acrolein is an undesirable event in whisky production, caused by infection of the broth with Klebsiella pneumoniae. This organism uses glycerol dehydratase to transform glycerol into 3-hydroxypropanal, which affords acrolein on distillation. The enzyme requires adenosylcobalamin (coenzyme B₁₂) as cofactor and a monovalent cation (e.g. K⁺). Diol dehydratase is a similar enzyme that converts 1,2-diols (C₂-C₄) including glycerol into an aldehyde and water. The subtle stereochemical features of these enzymes are exemplified by propane-1,2-diol: both enantiomers are substrates but different hydrogen and oxygen atoms are abstracted. The mechanism of action of the dehydratases has been elucidated by protein crystallography and ab initio molecular orbital calculations, aided by stereochemical and model studies. The 5'-deoxyadenosyl (adenosyl) radical from homolysis of the coenzyme's Co-C σ-bond abstracts a specific hydrogen atom from C-1 of diol substrate giving a substrate radical that rearranges to a product radical by 1,2-shift of hydroxyl from C-2 to C-1. The rearrangement mechanism involves an acid-base 'push-pull' in which migration of OH is facilitated by partial protonation by Hisα143, synergistically assisted by partial deprotonation of the non-migrating (C-1) OH by the carboxylate of Gluα170. The active site K⁺ ion holds the two hydroxyl groups in the correct conformation, whilst not significantly contributing to catalysis. Recently, diol dehydratases not dependent on coenzyme B₁₂ have been discovered. These enzymes utilize the same kind of diol radical chemistry as the coenzyme B₁₂-dependent enzymes and they also use the adenosyl radical as initiator, but this is generated from S-adenosylmethionine.

We have investigated the dependence of device characteristics of bulk-heterojunction organic thin-film solar cells on the concentration of glycerol and sorbitol addition in poly(3,4-ethylenedioxy thiophene):poly(4-styrene sulfonate) (PEDOT:PSS) solutions for fabricating buffer layers. The device structure is ITO/buffer/regioregular poly(3-hexylthiophene) (P3HT):[6,6]-phenyl C₆₁-butyric acid methylester (PCBM)/Al. Glycerol addition is effective for increasing power conversion efficiency (PCE) from 1.25 to 1.41% because of the increase in short-circuit current density (J_sc) without decreasing open-circuit voltage (V_oc). On the other hand, sorbitol addition decreases PCE from 1.25 to 1.04%, owing to the decrease in V_oc. This difference in V_oc behavior is ascribed to different work function of PEDOT:PSS with glycerol and sorbitol treatment.

Given the increasing demand for reducing environmental pollution by using clean energy, there is an urgent need to investigate new and more efficient alternatives for renewable resources use and clean energy production. Although biofuels such as, biodiesel represents a secure, renewable and environmentally safe alternative to fossil fuels. Its production is increasing considerably, and as a consequence, the amount of crude glycerol (main by-product) generated is growing exponentially. In order to solve future environmental problems of glycerol accumulation and to turn the biodiesel production economically viable, implementation of biotechnological strategies that use glycerol as the only carbon source to co-produce higher value products along with biofuels has been proposed as a solution to this problem. In this work it will be presented a well documented argument on the metabolic mechanism of different microorganism for glycerol assimilation. As well as description of different biotechnological processes using glycerol as substrate for bioconversion into different industrial bioproducts in Brazil.