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Abstract: This article provides a short survey on the thermodynamic and kinetic behaviour of cobalt complexes, which are able to bind molecular oxygen in aqueous solutions. The focus is on cobalt complexes with simple polyamines and with polynucleating ligands that share the same basic structure, in terms of them being elements of a sequence with increasing complexity. Ditopic polyazapolyoxalkanes and dicompartimental ligands containing a phenolic moiety are also considered. The aim is to elucidate the relation between the structure of the ligands and the behaviour of their cobalt complexes as donors and acceptors of dioxygen. [Copyright &y& Elsevier]

Abstract: Vapour–liquid equilibria (VLE), liquid–liquid equilibria (LLE), and excess enthalpies (H E) of binary mixtures of perfluoro-n-hexane plus an ether (diethyl, dipropyl, dibutyl, butyl methyl, and butyl ethyl ether), have been determined using a head-space gas-chromatographic technique, a turbidimetric apparatus, and a heat-flow calorimeter, respectively. A recently designed titration technique and calculation procedure have been used to obtain H E from heats of solution. The observed liquid–liquid coexistence curves have been compared with those predicted by the activity coefficients γ i and their temperature dependence. All mixtures are strongly endothermic (H E >0) and show large positive deviations from ideality (G E >0), which increase with the size of the ether. Molecular interactions have been examined by calculating and discussing solvation functions and Kirkwood–Buff (KB) integrals. Perfluorohexane proved to be an inert molecule that interacts with ethers more weakly than hexane. [Copyright &y& Elsevier]

Abstract: A newly designed calorimetric technique and calculation procedure have been used to obtain partial molar enthalpies, , and excess enthalpies, H E, for binary mixture of hexane+perfluoro-n-alkanes (C5–C8) and perfluorohexane+ n-alkanes (C5–C8), +cyclohexane, and +2-methylheptane. All mixtures are endothermic, and the heat effects increase with the size of the second component. The H E and values found are the largest ever observed for mixtures of non-polar compounds. An estimate of the excess heat capacity for (perfluorohexane+2-methylheptane) has been obtained from at two different temperatures. From at infinite dilution and from the known enthalpies of vaporization, the enthalpies of solvation, Δsolv H ∘, have been evaluated either for alkanes and perfluoroalkanes in both hexane and perfluorohexane solvent. Solute–solvent interactions have been examined by describing the Δsolv H ∘ with an additive scheme of surface interactions and by applying the Scaled Particle Theory. The effects of chain lengthening, branching, and cyclization have been discussed. Perfluoroalkanes proved to be inert molecules that interact weakly with themselves as well as with alkanes. [Copyright &y& Elsevier]

[Display omitted] • Physicochemical characterization of type-II DES/water mixtures. • Issues and potentialities of the techniques to study DES/water mixtures. • Type-II DES/water mixtures proposed as good media for microwave-assisted processes. • Indirect information on samples' nanostructures obtained by Nuclear Magnetic Resonance and Thermogravimetry. • Critical construction of Walden plot to assess samples' ionicity. Deep Eutectic Solvents (DESs)/water mixtures are widely proposed as unconventional green solvents in a wide range of applications. Here, we report a physicochemical characterization of type-II DESs (made by choline chloride and hexahydrate chloride of calcium or magnesium)/water mixtures, highlighting the potential of the techniques employed and their possible critical points. Viscosity, electrical conductivity, and density were measured at different temperatures and water contents and the data were analyzed to obtain information on the thermal expansibility coefficient, activation energy, and sample ionicity. Nuclear Magnetic Resonance and thermogravimetry provided additional information on the extent of the hydrogen-bond network in the mixtures. In addition, evaluation of microwave (MW) absorption capacity allowed us to classify the samples as suitable media for MW-assisted processes. Together, the information obtained made it possible to characterize the samples from both a structural and an application point of view. [ABSTRACT FROM AUTHOR]

A preface to the "Journal of Thermal Analysis & Calorimetry," by Maria Rosaria Tiné is presented.

Today, the need to dispose of a huge amount of ceramic industrial waste represents an important problem for production plants. Contextually, it is increasingly difficult to retrieve new mineral resources for the realization of building materials. Reusing ceramic industrial waste as precursors for building blocks/binders, exploiting their aluminosilicate composition for an alkaline activation process, could solve the problem. This chemical process facilitates the consolidation of new binders/blocks without thermal treatments and with less CO2 emissions if compared with traditional cements/ceramics. The alkali-activated materials (AAMs) are today thought as the materials of the future, eco-sustainable and technically advanced. In this study, six different kind of industrial ceramic waste are compared in their chemical and mineralogical composition, together with their thermal behaviour, reactivity in an alkaline environment and surface area characteristics, with the aim of converting them from waste into new resources. Preliminary tests of AAM synthesis by using 80%–100% of ceramic waste as a precursor show promising results. Workability, porosity and mechanical strengths in particular are measured, showing as, notwithstanding the presence of carbonate components, consolidated materials are obtained, with similar results. The main factors which affect the characteristics of the synthetized AAMs are the precursors' granulometry, curing temperature and the proportions of the activating solutions. [ABSTRACT FROM AUTHOR]

Geopolymers have been recently proposed for restoration of built heritage to substitute traditional mortars. Local materials and industrial wastes from the Italian region Sicily showed their potential as low-cost aluminosilicate sources for the preparation of geopolymers. Here, a set of Sicilian clays was studied by Thermogravimetry (TG) and Differential Scanning Calorimetry (DSC), and its mineralogical composition was evaluated by X-ray diffraction (XRD). The raw materials were used to prepare geopolymers by alkaline activation with or without the addition of silicate. The thermal degradation profile of the final materials was studied by TGA and compared with that of the precursors, and the energetics of dehydration were investigated by DSC. Two statistical analyses (made by Principal Component Analysis) were performed on the TG data of raw materials and geopolymers and on the TG data of geopolymers and their mineralogical composition, respectively. The last analysis in particular showed a correlation between the mineralogical composition of the materials and the samples' thermal properties. Additional studies of samples subject to accelerated aging by UV irradiation and exposure to acetic acid vapors highlighted the different effects of these two agents on the samples’ stability.Graphical abstract: Geopolymers have been recently proposed for restoration of built heritage to substitute traditional mortars. Local materials and industrial wastes from the Italian region Sicily showed their potential as low-cost aluminosilicate sources for the preparation of geopolymers. Here, a set of Sicilian clays was studied by Thermogravimetry (TG) and Differential Scanning Calorimetry (DSC), and its mineralogical composition was evaluated by X-ray diffraction (XRD). The raw materials were used to prepare geopolymers by alkaline activation with or without the addition of silicate. The thermal degradation profile of the final materials was studied by TGA and compared with that of the precursors, and the energetics of dehydration were investigated by DSC. Two statistical analyses (made by Principal Component Analysis) were performed on the TG data of raw materials and geopolymers and on the TG data of geopolymers and their mineralogical composition, respectively. The last analysis in particular showed a correlation between the mineralogical composition of the materials and the samples' thermal properties. Additional studies of samples subject to accelerated aging by UV irradiation and exposure to acetic acid vapors highlighted the different effects of these two agents on the samples’ stability. [ABSTRACT FROM AUTHOR]

This paper presents the results obtained from the thermal analysis of a set of geomaterials (clays, pyroclastic materials, and industrial recycled materials) to be used as raw materials for the synthesis of geopolymers, specifically designed for the conservation of Cultural Heritage (CH) buildings, particularly in seismic hazard zones such as Sicily. X-ray diffraction and gas volumetric analysis (calcimetry) were applied to this set of raw materials in order to characterize the materials from the chemical and structural point of view. Thermogravimetric analysis (TG), TG coupled to Fourier transform infrared spectroscopy (TG-FTIR), and differential scanning calorimetry were used to characterize their thermal behavior. The statistical treatment of the thermogravimetric data by principal component analysis and hierarchical clustering analysis highlights the direct relation between the thermal data and the material composition that will be exploited for the selection of the best materials to obtain geopolymers specifically designed for the conservation of CH buildings. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ageing of alkyd resin Winsor & Newton, Fast drying oil colour studied by ATR-FTIR. [•] The increase of the absorbance at 1635cm− 1 was selected as a parameter to follow the ageing process. [•] No extractive procedure, no destructive technique. [•] The carbonate of the filler and the carbonyl group of the esters react under acetic acid atmosphere. [•] A sample from a hyper-realistic artwork of Patrizia Zara was investigated to evaluate its natural ageing. [Copyright &y& Elsevier]

Limiting partial molar volumes of n-hexane, cyclohexane, ethyl ether, tetrahydrofuran, pentan-3-one and cyclopentanone in di-n-butyl ether, hexyl acetate and octan-2-ol were determined at 298.15 K from density measurements of dilute solutions carried out with a vibrating-tube densimeter. The solute–solvent interactions and the effects of the local organisation of the solvent around the solute molecules were discussed using the molar, void, and cavity volumes as different estimates of the intrinsic volume of the molecules. The analysis was then extended to the volumetric behaviour of the same solutes in octan-1-ol. The solvents examined interact with the solutes in different ways. The isomeric octanols show the most significant effects, possibly due to their H-bond donor nature. The solute–solvent interactions seem to prevail over the packaging effects in determining the volumetric behaviour of the solutes. [Copyright &y& Elsevier]

Graphical abstract Highlights • Protein-polymer conjugation with biodegradable polymers. • Multiple technique approach for the protein conjugate's characterization. • Proteins still folded and active in physiological conditions after bioconjugation. • Trend between the properties of the conjugates and the polymer molar mass. Abstract Protein-polymer conjugates are used to treat several diseases. PEGylation, i.e. the modification with poly(ethylene glycol) (PEG) is the currently used strategy. However, due to its non-biodegradability, the design of effective and degradable conjugates is of both academic and industry potential. We present the preparation and studies of the activity and stability of novel biodegradable myoglobin-polyphosphoester conjugates. Poly(ethyl ethylene phosphate) (PEEP) is a water-soluble polyphosphoester, which had been reported to be biocompatible and biodegradable. PEEP is a promising candidate as a degradable substitute for the "gold standard" PEG, which can cause long-term effects, as it is not degradable. PEEPylated conjugates with a variable degree of polymer grafting were synthesized, characterized (with online triple detection size exclusion chromatography, mass spectrometry, and gel electrophoresis), and compared with PEGylated analogs. We highlight differences in how the structure, the number, and the length of the polymer influence the properties of the conjugates. Overall, the analyses conducted (including activity assay, calorimetry, and fluorimetry measurements) show that the covalent attachment of the polymer does not irrevocably affect the protein's features under physiological conditions, suggesting the potential of this new class of polymers for the design of a new generation of fully degradable conjugates. [ABSTRACT FROM AUTHOR]

Novel green extractions aim at the full valorization of aromatic herbs along with the minimization of energy consumption, extraction time and cost of the processes. In this perspective, a simultaneous ultrasound and microwave irradiation extraction method (US-IMWAE) for the full valorization of aromatic herbs is here presented. This green approach has been applied to the isolation of essential oils (EOs), hydrosols and solid residues from lavender and rosemary plants. The yields of US-IMWAE in terms of EO weight percentage (wt%), polyphenols concentration and thermochemical characteristics of the solid residues have been compared with microwave assisted extraction (IMWAE) and hydrodistillation (HD). The composition profiles of EOs and hydrosols have been analyzed and quantified by head space gas chromatography mass spectrometry (HS-GC–MS), liquid chromatography with UV/visible diode array/fluorescence detector (HPLC-DAD-FD) and the Folin-Ciocalteu test for the total phenolic content (TPC). Solid residues as valuable by-products have been investigated by FTIR spectroscopy in tandem with chemometrics, thermogravimetric analysis (TGA) and combustion calorimetry. We found that the US-IMWAE green extraction method has produced higher yields of EOs with appealing composition profiles for cosmetic, fragrance and perfume industries (lavender), and for pharmacology and medical applications (rosemary). The high concentration of rosmarinic acid and the total phenolic content in hydrosols obtained with the US-IMWAE method, highlights its great potential. Chemometric analysis of solid residues has found that cellulose is the main component followed by hemicellulose and lignin. The experimental values of enthalpy of combustion of the solid residues (Δ c H) match with the corresponding calculated values and confirm their energetic features and their potential uses as alternative biomass for fuel production. US-IMWAE is environmentally friendly, highly flexible, controllable, and it enables to break the scale-up barrier in ultrasounds and microwave assisted industrial processes. Thus, US-IMWAE has a great potential to reduce EO production costs, and to increase local farm income through the full exploitation of aromatic herbs. [Display omitted] • Simultaneous irradiation of ultrasounds and microwaves in an integrated extractor. • Full valorization of aromatic herbs by exploiting the different fractions. • Combined ultrasonic and microwave irradiation enhances essential oil and hydrosol properties. • Enthalpy of combustion highlighted the energetic features of solid residues. • Green extraction in terms fast processing and for their innovative use of alternative energies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Preparation of type-II Deep Eutectic Solvents made by choline chloride and alkali-earth hydrated salts; • Optimization of the preparation procedure comparing conventional heating and heating with microwave-coaxial antenna, and by varying the water content; • Extended analyses of the samples' thermal properties by Hi-Res TGA, TGA-FTIR, DSC. • Evaluation of the samples' MW absorption capacity, highlighting their potential for future applications in MW-assisted processes. In this manuscript, we provided insights into the preparation of Deep Eutectic Solvents (DESs) made by choline chloride and MgCl 2 ·6H 2 O or CaCl 2 ·6H 2 O, proposed as green solvents for the valorization of biomasses, and we performed an extensive evaluation of their thermal properties. In particular, we highlighted the use of a microwave (MW) coaxial antenna as a rapid, efficient, and eco-friendly heating probe, which can reduce the preparation time up to 40 times with respect to conventional heating without altering the final properties of the product. The thermal properties of the DESs were extensively studied by Differential Scanning Calorimetry and High-Resolution Thermogravimetry with analysis of the evolved gas by Fourier Transformed Infra-Red spectroscopy, with the aim to obtain important information on their thermal stability and thermal degradation mechanism. The experimental data also allowed us to obtain indirect evidence of the hydrogen bonding network formed in DES nanostructures. Finally, the evaluation of the samples' capability to absorb MWs allowed us to classify them as good MW absorbers, highlighting their potential for future applications in MW-assisted processes. [ABSTRACT FROM AUTHOR]

Thermo analytical techniques and gas chromatography/mass spectrometry (GC/MS) were used to evaluate the presence of chemical-physical interactions between pine pitch and beeswax used as additive The mixtures found in several archaeological objects demonstrate that by modifying the physical and chemical properties of pitch and tar, our ancestors were able to add a variety of organic materials, such as waxes or animal fats. We studied pine pitch replicas from Pinus sylvestris prepared following a test from the field of experimental archaeology. Varying proportions of beeswax were added and then the resulting pitches were studied by a multi-analytical approach comprising the use of thermo analytical techniques (DSC, TG and TG-FTIR) and GC/MS, which provides molecular information. The same approach was also used to study a mixture of pitch from Pinus sylvestris L. and beeswax (“Zopissa”), whose relative proportions were unknown, and two archaeological adhesives collected from glass opus sectile fragments found in the northern necropolis of Antinoopolis (Egypt, 4th–5th century AD). Our thermo-analytical techniques managed to determine the relative proportion of pine pitch and additives, such as beeswax, in unknown archeological mixtures, and to evaluate the presence of interactions between pitch and additives. [ABSTRACT FROM AUTHOR]

A family of easily recoverable magnetic and thermally responsive composite materials, with nanoscale dimensions, were synthesized by a rapid and simple solvothermal approach. The synthesis was thermally activated, accelerated, and controlled using a coaxial antenna to directly apply the microwave energy inside the solvothermal reactor. The composite materials were made up by a confined phosphorylated nanoreactor, namely halloysite nanotubes grafted on the inner lumen with phosphoric acid (HNTs-(H+-PO 4)), that promoted the urea hydrolysis thus favoring the formation of a local alkaline environment to catalyze the homogeneous in situ precipitation of superparamagnetic iron oxide nanoparticles (IONs) selectively on their inner or outer surface. Two new MW-assisted solvothermal methodologies were used: 1) in the first the solvent is directly loaded into the MW-assisted reactor together with HNTs-(H+-PO 4) mechanically preloaded with iron chloride and urea in the lumen 2) in the second the synthesis is preceded by a further pre-functionalization step of the iron salt with clove essential oil (EO) as a green functionalization agent. Structural, morphological, textural, and magnetic properties were assessed by TEM, N 2 physisorption, TG-FTIR, ICP, XRD, magnetic and magnetic hyperthermia measurements. The MW-assisted solvothermal deposition of IONs was fully controlled using the phosphorylated nanoreactor, in short synthesis times, by a simple methodology following the principles of sustainable chemistry. IONs were selectively deposited on the outer surface or in the inner lumen of HNTs yielding easily recoverable superparamagnetic and thermally responsive nanocarriers suitable for applications like targeted hyperthermia therapy. [Display omitted] • in-situ urea hydrolysis and IONs deposition were promoted by HNTs-(H+-PO 4) nanoreactor. • Selective deposition of magnetic IONs in the inner or outer surfaces of HNTs-(H+-PO 4). • Good heating response of magnetic nanocomposites under a remotely applied magnetic field. • Green, fast and simple MW-assisted solvothermal deposition methodologies. • Magnetic and thermally responsive nanocarriers suitable for applications like targeted hyperthermia. [ABSTRACT FROM AUTHOR]

Highlights: [•] A Co(II)-polyamino-phenol complex able to bind dioxygen. [•] Crystal structure and DFT calculation of Co(III) and Co(II) dinuclear species. [•] Thermodynamic comparison {C}{C}among μ-peroxo-μ-hydroxo dinuclear species. [Copyright &y& Elsevier]

This paper presents an analytical investigation of paint reconstructions prepared with linseed oil that have undergone typical 19th century treatments in preparation for painting. The oil was mechanically extracted from the same seed lot, which was then processed by various methods: water washing, heat treatments, and the addition of driers, with and without heat. A modern process lead white (Dutch source, Schoonhoven) and a commercially available vine black were used as pigments. The reconstructions were prepared in 1999, and naturally aged from then onwards. We compared thermogravimetric analysis (TG), which yields macromolecular information, with gas chromatography-mass spectrometry (GC-MS) and direct exposure mass spectrometry (DEMS), which both provide molecular information. The study enabled us to quantitatively demonstrate, for the first time, that the parameters used to identify drying oils are deeply influenced by the history of the paint. In particular, here we show that the ratio between the relative amounts of palmitic and stearic acid (P/S), which is used as an index for differentiating between drying oils, is extremely dependent on the pigments present and the age of the paint. Moreover the study revealed that neither the P/S parameter nor the ratios between the relative amounts of the various dicarboxylic acids (azelaic over suberic and azelaic over sebacic) can be used to trace the sorts of pre-treatment undergone by the oil investigated in this study. The final results represent an important milestone for the scientific community working in the field, highlighting that further research is still necessary to solve the identification of drying oils in works of art. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports some recent results from the empirical evaluation of different types of structured molecular representations used in QSPR analysis through a recursive neural network (RNN) model, which allows for their direct use without the need for measuring or computing molecular descriptors. This RNN methodology has been applied to the prediction of the properties of small molecules and polymers. In particular, three different descriptions of cyclic moieties, namely group, template and cycle break have been proposed. The effectiveness of the proposed method in dealing with different representations of chemical structures, either specifically designed or of more general use, has been demonstrated by its application to data sets encompassing various types of cyclic structures. For each class of experiments a test set with data that were not used for the development of the model was used for validation, and the comparisons have been based on the test results. The reported results highlight the flexibility of the RNN in directly treating different classes of structured input data without using input descriptors. [Copyright &y& Elsevier]

Abstract: The removal of palladium, present as Pd(II), from aqueous solutions has been performed by a micellar-enhanced ultrafiltration process employing the cationic surfactant dodecyl-trimethylammonium chloride (DTAC). The effect of surfactant concentration and solution pH were investigated. Addition of DTAC at concentrations above the critical micellar concentration results in Pd(II) removal exceeding 95%. The possibility of Pd(II) recovery from the retentate was also examined. After the ultrafiltration process, metal ions are concentrated on the micelle surface. The addition of a strong electrolyte can be very useful to expel the metal from the micelles. Our results show that addition of aqueous MgCl2 at a concentration of 0.8M enables us to recover palladium with a yield of 66%. [Copyright &y& Elsevier]

Abstract: The extraction and recovery of cadmium from aqueous solutions has been performed by a method which avoids the use of organic solvents. The method makes use of surfactant micelles in combination with metal complexing agents. The complexed metals are concentrated on the micelle surface and then treated by a ligand-modified micellar enhanced ultrafiltration process (LM-MEUF). Subsequently the metal ions are stripped out of the micelle by addition of weakly acidic solutions of a strong electrolyte. Using the anionic surfactant sodium dodecylsulphate (SDS) and the azo-dye ligand pyridine-2-azo-p-dimethylaniline (PADA) we were able to extract Cd2+ from aqueous solution with high efficiency rates (∼99%). Once the metal has been extracted in the micellar pseudo-phase it has been recovered by means of NaCl 0.5moldm−3 acid solution. This procedure allows cadmium to be recovered from the aqueous solution with a yield of 80%. Moreover, the possibility of Cd(II) recovery in the presence of magnesium or zinc ions has been investigated. [Copyright &y& Elsevier]

Abstract: A recursive neural network QSPR model that can take directly molecular structures as input was applied to the prediction of the glass transition temperature of 277 poly(meth)acrylates. This model satisfactorily predicted the chemical–physical properties of high and low molecular weight acyclic compounds. However, side-chain benzene rings are present in about one half of the selected polymers. In order to render cyclic structures, the molecular representation through hierarchical structures was extended by two methods, named group and cycle breaking, respectively. The latter approach exploits standard unique molecular description systems, i.e. Unique SMILES and InChI. In all cases the prediction was very good, with 15–16K mean absolute error and 19–21K standard deviation. This result confirms the robustness of our method with respect to the inclusion of different structures. Moreover, the good performance of the cycle breaking representation paves the way for the investigation of data sets that contain a variety of poorly sampled cyclic structures. [Copyright &y& Elsevier]

Abstract: The kinetics of binding of Pd(II), initially present as PdCl4 2−, to the azo-dye ligand pyridine-2-azo-p-dimethylaniline (PADA) in dodecyltrimethylammonium chloride (DTAC) micellar solution has been investigated as a preliminary study on palladium micellar extraction and recovery. For comparison, the same investigation has been performed in water. Palladium reacts with PADA forming a strong 1:1 complex both in water and in DTAC micellar solution. Addition of DTAC, at concentrations just above the critical micellar concentration, results in a large enhancement of the rate of complex formation. The analysis of the kinetic behaviour reveals that several reaction paths are present. In water, under the experimental hydrogen ion concentration range investigated, reaction steps involving the protonated ligand forms PADAH+ and PADAH2 ++ are important and the reacting palladium species are PdCl4 2− and Pd(H2O)Cl3 −. In DTAC micellar solution, PADA reacts in its unprotonated form and a new reaction path appears involving the hydroxo species PdCl3OH2− which is about 10-times faster than the other reaction paths. The large catalytic effect produced by DTAC micellar solution provides a promising basis for the extraction of palladium from water using the PADA/DTAC system. [Copyright &y& Elsevier]

Excess molar volumes VE at 298.15 K have been determined by means of a vibrating-tube densimeter for binary mixtures of n-hexane with a perfluoroalkane, C5–C8, and of perfluorohexane with a n-alkane, C5–C8, or an ether (diethyl, dipropyl, dibutyl, butyl methyl, and butyl ethyl ether). The systems perfluoropentane+hexane, perfluorohexane+pentane or hexane or diethyl ether have been investigated in the entire mole fraction range, while the other mixtures only in the miscibility regions. The observed VE values are positive (up to 5.5 cm3 mol−1) and among the largest known for non-electrolyte systems. Limiting partial molar volumes, V¯°, have been evaluated for each component of the examined mixtures. The behaviour of V¯° has been discussed in terms of the scaled particle theory (SPT) and of a simple group additivity scheme based on surface interactions. An estimate has been made of the average separation distance of solvent from solute molecules. [Copyright &y& Elsevier]

Gelatin is a natural biopolymer extensively used for tissue engineering applications due to its similarities to the native extracellular matrix. However, the rheological properties of gelatin formulations are not ideal for extrusion-based bioprinting. In this work, we present an approach to improve gelatin bioprinting performances by using pectin as a rheology modifier of gelatin and (3-glycidyloxypropyl)trimethoxysilane (GPTMS) as a gelatin–pectin crosslinking agent. The preparation of gelatin–pectin formulations is initially optimized to obtain homogenous gelatin–pectin gels. Since the use of GPTMS requires a drying step to induce the completion of the crosslinking reaction, microporous gelatin–pectin–GPTMS sponges are produced through freeze-drying, and the intrinsic properties of gelatin–pectin–GPTMS networks (e.g., porosity, pore size, degree of swelling, compressive modulus, and cell adhesion) are investigated. Subsequently, rheological investigations together with bioprinting assessments demonstrate the key role of pectin in increasing the viscosity and the yield stress of low viscous gelatin solutions. Water stable, three-dimensional, and self-supporting gelatin–pectin–GPTMS scaffolds with interconnected micro- and macroporosity are successfully obtained by combining extrusion-based bioprinting and freeze-drying. The proposed biofabrication approach does not require any additional temperature controller to further modulate the rheological properties of gelatin solutions and it could furthermore be extended to improve the bioprintability of other biopolymers. [ABSTRACT FROM AUTHOR]

In this work, we have analysed the binding of the Pt(II) complexes ([PtCl(4′-phenyl-2,2′:6′,2″-terpyridine)](CF3SO3) (1), [PtI(4′-phenyl-2,2′:6′,2″-terpyridine)](CF3SO3) (2) and [PtCl(1,3-di(2-pyridyl)benzene) (3)] with selected model proteins (hen egg-white lysozyme, HEWL, and ribonuclease A, RNase A). Platinum coordination compounds are intensively studied to develop improved anticancer agents. In this regard, a critical issue is the possible role of Pt-protein interactions in their mechanisms of action. Multiple techniques such as differential scanning calorimetry (DSC), electrospray ionization mass spectrometry (ESI-MS) and UV-Vis absorbance titrations were used to enlighten the details of the binding to the different biosubstrates. On the one hand, it may be concluded that the affinity of 3 for the proteins is low. On the other hand, 1 and 2 strongly bind them, but with major binding mode differences when switching from HEWL to RNase A. Both 1 and 2 bind to HEWL with a non-specific (DSC) and non-covalent (ESI-MS) binding mode, dominated by a 1:1 binding stoichiometry (UV-Vis). ESI-MS data indicate a protein-driven chloride loss that does not convert into a covalent bond, likely due to the unfavourable complexes' geometries and steric hindrance. This result, together with the significant changes of the absorbance profiles of the complex upon interaction, suggest an electrostatic binding mode supported by some stacking interaction of the aromatic ligand. Very differently, in the case of RNase A, slow formation of covalent adducts occurs (DSC, ESI-MS). The reactivity is higher for the iodo-compound 2, in agreement with iodine lability higher than chlorine. [ABSTRACT FROM AUTHOR]

Mesoporous materials are very attractive solids for the fabrication of confined nanoreactors since they overcome the problems of diffusion/deactivation shown by microporous structures. In this work, we present the fabrication of a confined nanoreactor obtained by functionalization with phosphoric acid of the empty lumen (diameter 10–15 nm) of halloysite nanotubes (Hal). Two different halloysite nanoreactors with phosphorylated catalytic sites were prepared by the wet impregnation method followed by thermal activation: 1) phosphate modified Hal (starting with pristine Hal), and 2) phosphate-modified etched Hal (starting with etched Hal obtained by soft-etching pristine Hal using sulphuric acid). The selective grafting of hydrogen phosphate groups onto the aluminol active sites was characterized by solid-state nuclear magnetic resonance (1H, 27Al, 29Si HPDEC and 31P) and Fourier transform-infrared spectroscopies, and thermogravimetric and nitrogen physisorption analyses. Two different aluminum phosphate (Al O P) binding modes, monodentate (Al O P O(OH) 2) and bidentate (Al O) 2 P(OH) 2 , with different distributions were observed in both phosphorylated-Hal nanoreactors. The selective functionalization of the internal lumen was confirmed because no interaction (due to Si O P binding mode) was detected between the outer surface of Hal and phosphoric acid. The confined nanoreactors prepared here preserved the main chemical structure and textural properties of Hal. The analysis of the specific surface area and mesopore size showed that, depending on the starting material, grafting the phosphate groups led to the formation of a monolayer or a polycondensation of phosphate moieties inside the tubular mesopore. However, in both prepared nanoreactors, phosphorylation did not result in saturating the material or pore blocking. These mesoporous materials could be used in catalysis and in situ nanoparticle synthesis. Unlabelled Image • Selective grafting of hydrogen phosphate groups onto the inner surface of Hal • Fabrication of a mesoporous confined nanoreactor with phosphorylated catalytic sites • Hal morphology and chemical arrangement were maintained after the grafting. • Phosphorylation process does not result in saturation or pore blocking. • Two different Al-O-P binding modes with a different distribution were observed. [ABSTRACT FROM AUTHOR]