Use of cellulose nanofibril (CNF)/silver nanoparticles (AgNPs) composite in salt hydrate phase change material for efficient thermal energy storage.

Salt hydrate phase change materials (PCMs) possess the challenge of supercooling, which must be addressed to allow more efficient energy storage and utilisation. In this work, cellulose nanofibril (CNF), a versatile biopolymer was used to support and disperse silver nanoparticles (AgNPs), and the synthesised CNF/AgNPs composite was used to improve the performance of sodium acetate trihydrate (SAT). Results showed that CNF dispersed the AgNPs uniformly and prevented their aggregation. Through the synergistic effect of 1% CNF/AgNPs and 2% sodium phosphate dibasic dodecahydrate, a low supercooling degree of 1.2 °C was achieved. Moreover, AgNPs were uniformly distributed in the prepared PCM composite. Differential scanning calorimetry results indicated that the prepared PCM@CNF/AgNPs 0.02 composite showed a similar melting point (57.4 °C) and enthalpy (269 kJ/kg), compared to those of pure SAT. Thermogravimetric analysis showed that the PCM composite did not lose all moisture until a heating temperature of 160 °C, showing improved thermal stability. The thermal conductivity of PCM@CNF/AgNPs 0.02 composite was 31.6% higher than that of SAT. The enthalpy of this composite decreased only around 2% after 100 melting/freezing cycles, showing satisfying thermal reliability. This composite can therefore be used to fabricate high-performance TES systems with negligible supercooling and improved thermal properties.

Supramolecular effect of acetate on chitin gelling medium: Structural properties and protein interaction.

In this work, the influence of Sodium Acetate Trihydrate (SAT) on the gelling stage of a chitin hydrogel was studied. Characterization techniques, such as FTIR, Raman, solid-state NMR, Dielectric Spectroscopy, Small-angle X-ray scattering (SAXS), Wide-angle X-ray scattering (WAXS), and X-ray diffraction (XRD) were used to study the effect of SAT on the micro and nanostructure of the material in the wet, dry and freeze-dried states. It was demonstrated that the amount of SAT in the gelling solution can induce a variation in the supramolecular interaction among the polysaccharide chains, which leads to a change in the structural characteristics. In addition, it was observed that the polymer-water interactions are also altered by this structural ordering. Also, the affinity interaction with lysozyme was evaluated and an influence on the adsorption capacity was evidenced with the use of SAT. This could be an advance for biotechnological, biomedical, and food applications.

Optimization of the radiosynthesis of [68Ga]Ga-PSMA-11 using a Trasis MiniAiO synthesizer: do we need to heat and purify?

INTRODUTION:: [Ga]Ga-prostate specific membrane antigen (PSMA)-11 showed a clear gain in sensitivity for lesion detection in the biological recurrence of prostate cancer as compared to the standard [F]fluorocholine radiopharmaceutical. To meet the strong demand for [Ga]Ga-PSMA-11, we aimed to optimize an automated radiolabeling process by evaluating the influence of different key parameters on radiochemical purity and radiochemical yield. METHODS: The radiosynthesis of [Ga]Ga PSMA-11 was performed using a Trasis MiniAio synthesizer and a Ge/Ga GalliaPharm generator supplied by Eckert & Ziegler, Berlin, Germany. Optimized labeling parameters were evaluated by variation of sodium acetate concentrations and temperature of radiolabeling as well as the purification process. RESULTS: For each condition tested, radiochemical purity was higher than 99% in the final vial without batch failure, indicating a robust and fast radiosynthesis process. Radiosynthesis without the solid phase extraction purification process at room temperature in less than 5 min resulted in a radiolabeling efficiency of over 99% and remained stable at least 4 h without manual processing to limit operator radiation exposure. CONCLUSION: The procedure was completely automated and provided a high radiochemical yield. It can be performed several times a day, facilitating the clinical demand of this radiopharmaceutical.

Antibacterial effects of plant extracts with hurdle technology against Vibrio cholerae.

Vibrio cholerae is an etiological cause of cholera implicated in several pandemics. Antibacterial activity of plant extracts has been established. However, these extracts exhibit activity at a concentration that may alter organoleptic attributes of water and food, hence limiting their application. In this light, there is need to device ways of reducing plant extracts' effective levels in order to widen their application. Thus, this study was conducted to improve activities of plant ethanolic extracts through combination with other generally recognized as safe antimicrobials. Combination of plant extracts with sodium acetate (NaOAc) 0.4% at pH 7.0 reduced minimum inhibitory concentrations (MICs) of clove, lemon eucalyptus, rosemary and sage from 0.2 to 0.025%. At pH 6.4, combinations were more effective reducing MICs of clove, lemon eucalyptus, rosemary and sage from 0.2 to 0.0125% with NaOAc at 0.2%. At pH 7.0, the combination resulted in additive effect. Nevertheless, at pH 6.4, synergic effect was established. No interactive effect was observed with combinations involving glycine. Combination of plant extracts with NaOAc at mildly acidic pH creates a hurdle effect that may have potential application to control the growth of V. cholerae.

Relation of Colloidal and Conformational Stabilities to Aggregate Formation in a Monoclonal Antibody.

Aggregation of therapeutic monoclonal antibodies has a potential risk of immunogenicity, requiring minimization of aggregate formation. We have developed a fitting formula for antibody aggregation at 40°C based on physicochemical parameters, including colloidal and conformational stabilities. An IgG1 monoclonal antibody, MAb-T, was formulated in 24 combinations of different buffer types and pH with or without sodium chloride. The fitting formula for monomer loss was successfully established by nonlinear regression analysis of the results from accelerated stability testing. Calculated monomer fraction values by the fitting formula were strongly correlated with experimental values (R2 = 0.92). The model includes secondary virial coefficient, B22, as the representative parameter of colloidal stability, and aggregation temperature, Tagg, representing conformational stability. Then, we examined charge state, conformational flexibility, and thermal unfolding profile of MAb-T to clarify the molecular basis for the different aggregation propensities in sodium acetate buffer and in sodium citrate buffer at the same pH and buffer concentration. We concluded that the accumulation of citrate anions on the surface of MAb-T is the primary source of the less colloidal and conformational stabilities, resulting in the higher aggregation propensity in sodium citrate buffer.

Optimization of routine microscopic and molecular detection of parasitic protozoa in SAF-fixed faecal samples in Sweden.

Background: Nucleic acid-based methods are increasingly used for screening of gastrointestinal parasites. Microscopy is still used and Swedish routine protocol consists of formalin ethyl-acetate concentration and do not include screening for trophozoites or Cryptosporidium spp. This study aimed to compare detection with the Swedish routine microscopy method to an extended method that includes screening for trophozoites and Cryptosporidium. Furthermore, we also developed a method for DNA recovery from SAF-fixed faecal samples and compared the real-time PCR detection of Giardia intestinalis, Dientamoeba fragilis, Cryptosporidium spp., Entamoeba histolytica and Entamoeba dispar from SAF-fixed and unpreserved faecal samples. PCR results were then compared with microscopy results.Methods: SAF-fixed and unpreserved faecal samples from 1000 patients at the Clinical microbiology laboratory in Region Jönköping County, Sweden, were included. Samples were analysed with routine formalin ethyl-acetate concentration, wet mounts from both concentrated and unconcentrated samples, Ziehl-Neelsen staining on patients with certain symptoms and real-time PCR.Results: We found a significant higher detection rate of parasites with the extended microscopy method compared to the Swedish routine microscopy method when SAF-fixed samples were used. The detection rate with real-time PCR in SAF-fixed samples was equal to the detection rate in unpreserved samples. There was no significant difference in detection comparing extended microscopy and real-time PCR.Conclusion: In conclusion, this study showed that the extended microscopy method increased detection of intestinal protozoa with detection of both trophozoites and Cryptosporidium spp. We also showed that SAF-fixative can be used for detection of parasite-DNA with real-time PCR.

Isolation, Purification, Characterization and Direct Conjugation of the Lipid†A-Free Lipopolysaccharide of Vibrio cholerae O139.

The lipopolysaccharide (LPS) of Vibrio cholerae O139, strain CIRS245, was isolated conventionally, and the lipid A was removed by mild acid hydrolysis (0.1 m NaOAc buffer containing 1 % SDS, pH 4.2, 95 °C, 8 h). The crude product was a complex mixture consisting mainly of constituent fragments of the O-specific polysaccharide-core (OSPc). The OSPc was only a minor component in the mixture. Two-stage purification of the crude OSPc by HPLC gave pure OSPc fragment of the LPS, as shown by NMR spectroscopy, analytical HPLC and ESI-MS. This material is the purest OSPc fragment of the LPS from Vibrio cholerae O139 reported to date. The purified OSPc was readily converted to the corresponding methyl squarate derivative and the latter was conjugated to BSA. The conjugate, when examined by ELISA, showed immunoreactivity with sera from patients in Bangladesh recovering from cholera caused by V. cholerae O139, but not O1.

Molecular and technical aspects on the interaction of serum albumin with multifunctional food preservatives.

Synthetic food preservatives like sodium acetate (SA), sodium benzoate (SB), potassium sorbate (PS) and Butyl paraben (BP) have been widely used in food and pharmacy industries. One of the toxicological aspects of food additives is evaluation of their interaction with serum proteins such as albumin. These additives interaction with human serum albumin (HSA) can exert considerable effect on the absorption, distribution, metabolism and toxicity of chemical compounds. It should be noticed that the aforementioned food preservatives intake increase mainly in the presence of glucose may lead to complex formation of SA, SB, PS and BP with HSA and accelerate the development of variety disease such as cancer, diabetes, multiple sclerosis, brain damage, nausea and cardiac disease. Therefore, to understand the mechanisms of aforementioned food additives interaction and conformational changes of proteins, we aim to review various studies that investigated albumin interaction with these additives using several procedures.

Characterisation of aluminium release by the enFlow® fluid-warming system in crystalloids and blood products.

The use of uncoated aluminium-heated plates in an intravenous fluid-warming system has been shown to produce high levels of aluminium in Sterofundin 1/1E, a balanced crystalloid solution. However, the effect of this fluid-warming device on other balanced crystalloid solutions and blood products has not been studied. Using mass spectrometry we measured aluminium levels in Plasma-Lyte 148, compound sodium lactate solution, 4% human albumin solution, expired resuspended packed red cells and fresh frozen plasma that were pumped through an enFlow® fluid-warming system at 2 ml.min-1 . Samples were taken at baseline before heating and then at 10-min intervals up to 60 min with the system set to warm the fluids to 40 °C. High concentrations of aluminium were found for Plasma-Lyte 148 and compound sodium lactate solutions (mean (SD) 223 (0.6) µmol.l-1 and 163 (0.2) µmol.l-1 at 60 min, respectively); both concentrations were significantly greater than the United States Food and Drug Administration recommended maximum limit for aluminium in intravenous nutrition of 25 µg.l-1 (0.9 µmol.l-1 ). Lower aluminium levels were found in 4% human albumin solutions, expired resuspended red cells and fresh frozen plasma at 60 min (mean (SD) 5.7 (0.1) µmol.l-1 , 2.7 (0.0) µmol.l-1 and 2.3 (0.4) µmol.l-1 , respectively). The process allowing addition of aluminium to be added to Sterofundin 1/1E by the enFlow fluid warmer also occurs in Plasma-Lyte 148 and compound sodium lactate solutions and to a lesser degree in blood products. The exact mechanism facilitating this process and its clinical significance remain unclear.

14C-Labelling of the natural steroid estrogens 17α-estradiol, 17ß-estradiol, and estrone.

The worldwide environmental occurrence of natural steroid estrogens has drawn increasing concerns. However, the fate of the estrogens, especially the α-isomer of estradiol, in the environmental matrices is still obscure. Using 14C-radioactively labelled forms of these estrogens can facilitate and is sometimes a prerequisite for studying their transformation and residual distribution in the environment, but the availability of labelled compounds (owing to commercially high prices or unavailable) hampers such studies. Here we developed simple and stable methods to synthesize 14C-labelled estradiol isomers and estrone using relatively low-priced [carboxyl-14C]-labelled sodium acetate as a precursor. The radiochemical syntheses started from an enol lactone, which was prepared from nandrolone by oxidation to open the A-ring followed by recyclization. Inversion of the 17ß-hydroxyl group into its 17α-form was achieved via the Walden inversion using the Mitsunobu reaction. [3-14C]-17ß-estradiol, [3-14C]-17α-estradiol, and [3-14C]-estrone were synthesized in five, six, and seven steps with an overall radiochemical yield of 17.4%, 16.2%, and 13.9%, respectively. The synthesized 14C-labelled compounds provide materials for studying the fate and behavior of estrogens in complex environmental matrixes and for further synthesis of their 14C-labelled sulfate and glucuronide conjugates.

Application of combined acetate salt based multiple analyte adduct formation in signal separated quantification performed for the purposes of forensic toxicology with liquid chromatography-tandem mass spectrometry - Discussion on the basis of salicylic acid applied as a model drug.

In this work the examination of analyte adduct formation by the application of both sodium acetate and lithium acetate was performed with salicylic acid used as a model drug. Additionally, on the basis of combined acetate salt based multiple analyte adduct ions it was aimed to investigate the generation of different analyte precursor ions and their application in signal separated quantification with liquid chromatography-tandem mass spectrometry. Adduct identification experiments were performed by infusion experiments and resulted in an optimised detection of analyte adduct ions with lithium acetate, sodium acetate and combined lithium acetate/sodium acetate. Sample preparation based on a fast protein precipitation with a methanol solution containing lithium acetate and sodium acetate. A Luna 5 µm C18 (2) 100 A, 150 mm × 2 mm analytical column and a mobile phase composed of an H2O/methanol = 3%/97% (v/v) solution with 10 mmol l-1 ammonium acetate and 0.1% acetic acid were used for chromatographic purposes. The linearity was investigated in the range of 5-500 µg/ml. The limit of detection (LOD of 1.2 µg/ml) and quantification (LOQ 4.0 µg/ml) together with other results of validation experiments revealed that this strategy can be applied for salicylic acid quantification.

Extending the Lifespan of Soluble Lead Flow Batteries with a Sodium Acetate Additive.

In this report, we present a method for the construction of a soluble lead flow battery (SLFB) with an extended cycle life. By supplying an adequate amount of sodium acetate (NaOAc) to the electrolyte, a cycle life extension of over 50% is demonstrated for SLFBs via long-term galvanostatic charge/discharge experiments. A higher quality of the PbO2 electrodeposit at the positive electrode is quantitatively validated for NaOAc-added electrolyte by throwing index (TI) measurements. Images acquired by scanning electron microscopy (SEM) also exhibit more integrated PbO2 surface morphology when the SLFB is operated with the NaOAc-added electrolyte. This work indicates that electrolyte modification can be a plausible route to economically enable SLFBs for large-scale energy storage.

Physico-chemical stability of Plasma-Lyte 148® and Plasma-Lyte 148® + 5% Glucose with eight common intravenous medications.

BACKGROUND: Plasma-Lyte 148® is a balanced, crystalloid intravenous (IV) fluid which is both calcium-free and isotonic. It prevents the hyperchloremic metabolic acidosis and iatrogenic hyponatremia seen with use of 0.9% sodium chloride and hypotonic solutions, respectively. However, data on compatibility with commonly used drugs are lacking. AIMS: To investigate the stability of Plasma-Lyte 148® and Plasma-Lyte 148® + 5% Glucose with eight commonly used therapeutic agents when compared with 5% glucose and 0.9% sodium chloride as diluents. We aimed to provide vital data which may facilitate the introduction of what appears to be a safer and more economic fluid. METHODS: Plasma-Lyte 148® and Plasma-Lyte 148® + 5% Glucose were mixed with morphine, midazolam, fentanyl, ketamine, clonidine, aminophylline, salbutamol, and furosemide at set concentrations. Comparisons were made to 0.9% sodium chloride and 5% glucose fluid controls. Six repeats of each IV fluid and drug admixture were analyzed through high-performance liquid chromatography at three time points: 0, 2, and 24 hours. A concentration change of <5% was defined as chemically stable. Physical stability was assessed by observation of precipitate formation or color change. pH changes were measured using a Fisherbrand Hydrus 300 pH meter. RESULTS: Relative to starting concentration, all drugs except midazolam were stable to ±3%. All examined therapeutic agents were chemically stable at 2 and 24 hours relative to control solutions. No precipitate formed in any of the samples. All Plasma-Lyte 148® and Plasma-Lyte 148® + 5% Glucose drug admixtures remained in a safe, peripheral administration pH range of 5-9 and were closer to the pH of blood than standard fluid-drug admixtures. CONCLUSION: Morphine, fentanyl, ketamine, salbutamol, aminophylline, and clonidine are stable for 24 hours when mixed with Plasma-Lyte 148® and Plasma-Lyte 148®+5% Glucose for administration at concentrations equivalent to those found at a typical Y-site with maintenance fluid. Furosemide is stable at lower concentrations than those seen at a Y-site, but midazolam displayed instability.

Tofogliflozin Salt Cocrystals with Sodium Acetate and Potassium Acetate.

We investigated the salt cocrystals formed by tofogliflozin with sodium acetate and potassium acetate by determining the crystal structures of the salt cocrystals and characterizing the solid states. The salt cocrystal screening using the slurry method and the liquid-assisted grinding method resulted in the formation of tofogliflozin-sodium acetate 1 : 1 and tofogliflozin-potassium acetate 1 : 1 salt cocrystals. Single-crystal X-ray diffraction revealed that, although each salt cocrystal belongs to a different space group, both of the salt cocrystals have almost similar structural features, including the conformation of tofogliflozin molecules, the coordination to Na+/K+ ions, and hydrogen bonds. The salt cocrystals exhibited extreme hygroscopicity with deliquescence, which is also a property of sodium acetate and potassium acetate. In addition, tofogliflozin-potassium acetate salt cocrystal had two polymorphs, which were enantiotropically related.

Optimization of a Labeling and Kit Preparation Method for Ga-68 Labeled DOTATATE, Using Cation Exchange Resin Purified Ga-68 Eluates Obtained from a Tin Dioxide 68Ge/68Ga Generator.

PURPOSE: The aim of this study was to optimize a radiolabeling method using cationic processed Ga-68 eluates from a SnO2-based 68Ge/68Ga generator, followed by the development of DOTA-Tyr3-Thre8-octreotide (DOTATATE) kits. PROCEDURES: Diluted generator eluates were adsorbed on a SCX resin and desorbed with acidified 5 M NaCl solution. Optimized labeling conditions were determined by variation of pH, using 35 µg DOTATATE and sodium acetate buffer. DOTATATE kits were developed based on optimized radiolabeling conditions, were labeled, and evaluated. RESULTS: Optimized labeling conditions resulted in a radiolabeling efficiency of around 99 % and radiochemical yield of almost 85 %. Different kit preparation methods did not significantly influence the radiolabeling results. Kits were found to be stable over 3 months. CONCLUSION: A labeling method using SCX-processed Ga-68 eluates was optimized. DOTATATE kits specifically for these SCX-processed Ga-68 eluates were successfully formulated. A post-labeling Sep-Pak C18 purification should be optional.

Engineering fast dissolving sodium acetate mediated crystalline solid dispersion of docetaxel.

It is hypothesized that a novel crystalline solid dispersion (CSD) of docetaxel (C-DXT) can be engineered by dispersing native docetaxel (DXT, a BCS class II drug) in sodium acetate crystal (SA). DXT is dissolved in glacial acetic/SA solution and freeze-dried. The resulting C-DXT is characterized by differential scanning calorimetry (DSC), powder X-ray analysis (PXRD), LC-MS/MS, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Quartz crystal microbalance with dissipation monitoring (QCM-D) and dynamic light scattering (DLS). Its cytotoxicity on model cancerous (MCF-7, MDA-MB-468) and normal breast cells (MCF-10A) is assessed by MTS assay. SEM/TEM data and the absence of the characteristics peaks of DXT on the DSC curve (at 193.4 °C) and the XRD scan (at 2θ = 15.31 °C and 23.04 °C) confirm the presence of C-DXT in SA. The LC-MS/MS data indicates the chemical stability of DXT. The yield and C-DXT loading are 95.2% and 6.52% w/w, respectively. The C-DXT rapidly forms an aqueous non-rigid nanosuspension with a faster drug dissolution rate compared to native DXT. Unlike, control Tween 80/ethanol, SA is noncytotoxic to normal cells. However, C-DXT's cytotoxicity is time and dose dependent for all diseased cells. This unique CSD process might be applicable to other hydrophobic bioactive agents to enhance their safety and efficacy.

Safety assessment of sodium acetate, sodium diacetate and potassium sorbate food additives.

Cytotoxicity and genotoxicity of sodium acetate (SA), sodium diacetate (SDA), and potassium sorbate (PS) was tested on Human Umbilical Vein Endothelial Cells (HUVEC). Cytotoxicity was investigated by MTT assay and flow cytometry analysis, while genotoxicity was evaluated using DNA fragmentation and DAPI staining assays. The growth of treated HUVECs with various concentrations of SA, SDA and PS decreased in a dose-and time-dependent manner. The IC50 of 487.71, 485.82 and 659.96 µM after 24 h and IC50 of 232.05, 190.19 and 123.95 µM after 48 h of treatment were attained for SA, SDA and PS, respectively. Flow cytometry analysis showed that early and late apoptosis percentage in treated cells was not considerable. Also neither considerable DNA fragmentation nor DNA smear was observed using DAPI staining and DNA ladder assays. Overall, it can be concluded that the aforementioned food additives can be used as safe additives at low concentration in food industry.

Self-aggregation of water-dispersible nanocollagen helices.

Inspired by nature, collagen is an outstanding polypeptide utilized to exploit its bioactivity and material design for healthcare technologies. In this study, we describe the self-aggregation of water-dispersible nanocollagen helices upon solidification to fabricate different forms of natural collagen materials. Chemically extracted native collagen fibrils are uniform anisotropic nanoparticles with an average diameter of about 50 nm and a high aspect ratio. The as-prepared collagen nanofibrils are soluble in sodium acetate-acetic acid buffer and are dispersible in water, thus generating collagen liquids that are used as distinct biopolymer precursors for materials development. Our interesting findings indicate that water-dispersible collagen-derived alcogels undergo critical point drying to self-arrange hierarchical nanofibrils into helix bundles in collagen sponge-like aerogels. Notably, using lyophilization to remove water in the biopolymer dispersion, a full regeneration of solidified fibers is achieved, producing collagen aerogels with lightweight characteristics similar to natural cottons. The self-aggregation of water-dispersible collagen occurs under freeze-drying conditions to turn individual nanofibrils into sheets with layered structures in the aerogel networks. The development of transparent, water resistant collagen bioplastic-like membranes was achieved by supramolecular self-assembly of water-dispersible collagen nanofibrils. Our efforts present a reliable concept in soft matter for creating promising collagen examples of liquids, hydrogels, aerogels, and membranes to increase utilization value of native collagen for biomedicine, pharmaceuticals, cosmetics, and nutrients.

Pyrazines from bacteria and ants: convergent chemistry within an ecological niche.

Ants use pheromones to coordinate their communal activity. Volatile pyrazines, for instance, mediate food resource gathering and alarm behaviors in different ant species. Here we report that leaf-cutter ant-associated bacteria produce a family of pyrazines that includes members previously identified as ant trail and alarm pheromones. We found that L-threonine induces the bacterial production of the trail pheromone pyrazines, which are common for the host leaf-cutter ants. Isotope feeding experiments revealed that L-threonine along with sodium acetate were the biosynthetic precursors of these natural products and a biosynthetic pathway was proposed.

Toxicity assessment of the extractables from multi-layer coextrusion poly ethylene bags exposed to pH=5 solution containing 4% benzyl alcohol and 0.1 M sodium acetate.

A non-target analysis was developed for the analysis of extractables from multi-layer coextrusion bags exposed to 4% benzyl alcohol solution and 0.1 M sodium acetate at pH = 5 for defined periods (15 day, 45 day and 90 day) according to manufacturer instructions based on the ultra-performance liquid chromatography (UPLC) quadrupole-time of flight mass spectrometry (Q-TOF MS). In order to confirm the extractables, principal component analysis (PCA) was used to indicate the differences among samples of different periods. Then, the extractables were identified based on searching the self-built library or online searching. The total content of extractables of 90 day samples was 589.78 µg/L, and the content was in the range of acceptable levels for pharmaceutical manufacturers. The risk assessment of the extractables were evaluated by Toxtree and T.E.S.T. software to avoid the animals bioexperiment.