Soluble Acid Research Articles

Application ICP-OES to Multielement Analysis on Plastic Waste and Blends with Vacuum Gas Oil: Developing a Sample Preparation Protocol

This paper introduces a new methodology for a routine metal analysis of plastic waste (PW) and PW blended with petroleum feedstock such as vacuum gas oil and VGO (PW/VGO). For such purposes, recycled polyethylene and polypropylene plastic were selected to mimic the potential feeds to be integrated at the Fluid Catalytic Cracking unit (FCC) to produce valuable products. Elements such as P, Ca, Al, Mg, Na, Zn, B, Fe, Ti, and Si were included in the method development. Different sample preparation methods were evaluated, such as microwave-assisted acid digestion (MWAD) and dry/wet ashing, followed by a fusion of the ash with lithium borate flux. Some PW homogenization pretreatments, such as cryogenic grinding and hot press molding, were also covered. The finding of this work suggests that MWAD with HNO3 and H2O2 is adequate for both types of samples and is the quickest sample preparation; however, the sample needed to be homogenized, and recoveries for Si and Ti may be biased for PW due to the limited solubilities of these elements in the nitric acid media. Carbon removal is required before fusion sample preparation and analysis due to the amount of carbon in PW samples. The sample needed to be homogenized for wet ash fusion but not for the pre-ash (dry) method. A benefit to the damp ash pretreatment is that the ash for the sample was created in the same crucible used for fusion digestion, avoiding material loss during sample management. Fusion from wet ash or carbon removal allowed for better acid solubility for Si and Ti in PW. The results of the PW samples evaluated matched well with those of both sample preparation methodologies. For most elements, precision was <10% regardless of the sample preparation; however, Fe and P had some variation using wet ash fusion, possibly due to contamination in an open digestion system or variation due to being close to the method limit of quantification (LOQ). The methodology reported here is robust enough to be implemented as routine analysis in any laboratory facility.

Preparation and characterization of quartz ceramic proppant replacing natural quartz sand by solid waste silica fume

AbstractThe improper disposal of industrial wastes will cause environmental pollution and economic losses due to the loss of active ingredients. Solid waste silica fume and pyrolusite powder were used to synthesize quartz ceramic proppant by pelleting and sintering to replace natural quartz sand for unconventional oil and gas exploitation. The effects of pyrolusite powder content and sintering temperature on the apparent density, breakage ratio, and acid solubility of the proppant were thoroughly studied. The phase composition and microstructure of the proppant were characterized by X‐ray diffraction and scanning electron microscopy, respectively. The results revealed that the main crystal phase of the proppant prepared without pyrolusite was cristobalite, while that with pyrolusite was cristobalite and quartz, and the content of quartz phase increased gradually with increasing the pyrolusite content. The addition of pyrolusite remarkably increased the density and improved the performance of the proppant due to the resulting glass phase at high temperatures and the presence of andradite. As adding 20% pyrolusite, the apparent density of the proppant sintered at 900°C was 2.26 g/cm3, while the breakage ratio under 28 MPa closed pressure and acid solubility reached the minimum, 9.89% and 5.3%, respectively, meeting the industrial standard requirements.

Improving Water Solubility of Docosahexaenoic Acid with Chickpea Protein Isolates Deamidated by Protein-glutaminase

Improving Water Solubility of Docosahexaenoic Acid with Chickpea Protein Isolates Deamidated by Protein-glutaminase

Exploring Deep Eutectic Solvents as Pharmaceutical Excipients: Enhancing the Solubility of Ibuprofen and Mefenamic Acid.

Objectives: The study explores the potential of various deep eutectic solvents (DESs) to serve as drug delivery systems and pharmaceutical excipients. The research focuses on two primary objectives: evaluating the ability of the selected DES systems to enhance the solubility of two poorly water-soluble model drugs (IBU and MFA), and evaluating their physicochemical properties, including density, viscosity, flow behavior, surface tension, thermal stability, and water dilution effects, to determine their suitability for pharmaceutical applications. Methods: A range of DES systems containing pharmaceutically acceptable constituents was explored, encompassing organic acid-based, sugar- and sugar alcohol-based, and hydrophobic systems, as well as menthol (MNT)-based DES systems with common pharmaceutical excipients. MNT-based DESs exhibited the most significant solubility enhancements. Results: IBU solubility reached 379.69 mg/g in MNT: PEG 400 (1:1) and 356.3 mg/g in MNT:oleic acid (1:1), while MFA solubility peaked at 17.07 mg/g in MNT:Miglyol 812®N (1:1). In contrast, solubility in hydrophilic DES systems was significantly lower, with choline chloride: glycerol (1:2) and arginine: glycolic acid (1:8) showing the best results. While demonstrating lower solubility compared to the MNT-based systems, sugar-based DESs exhibited increased tunability via water and glycerol addition both in terms of solubility and physicochemical properties, such as viscosity and surface tension. Conclusions: Our study introduces novel DES systems, expanding the repertoire of pharmaceutically acceptable DES formulations and opening new avenues for the rational design of tailored solvent systems to overcome solubility challenges and enhance drug delivery.

Optimization of drug solubility inside the supercritical CO2 system via numerical simulation based on artificial intelligence approach

In this research paper, we explored the predictive capabilities of three different models of Polynomial Regression (PR), Extreme Gradient Boosting (XGB), and LASSO to estimate the density of supercritical carbon dioxide (SC-CO2) and the solubility of niflumic acid as functions of the input variables of temperature and pressure. The optimization of hyperparameters for these models is achieved using the innovative Barnacles Mating Optimizer (BMO) algorithm. For SC-CO2 density estimation, PR exhibits remarkable accuracy, showing an R-squared value of 0.99207 for data fitting. XGB performs admirably with an R2 of 0.92673, while LASSO model demonstrates good predictive ability, showing an R2 of 0.81917. Furthermore, we assess the models’ performance in predicting the solubility of niflumic acid. PR exhibits excellent predictive capabilities with an R2 of 0.96949. XGB also delivers strong performance, yielding an R-squared score of 0.92961. LASSO performs well, achieving an R-squared score of 0.82094. The results indicated promising performance of machine learning models and optimizer in estimating drug solubility in supercritical CO2 as the solvent applicable for pharmaceutical industry.

Synergistic effect of cyclodextrins and electrolytes at high concentrations on protein aggregation inhibition

The stabilization of protein therapeutics against aggregation is crucial for maintaining their efficacy and safety. This study investigated the synergistic effects of cyclodextrins (CDs) and electrolytes at high concentrations on the stabilization of immunoglobulin G (IgG), insulin, and adeno-associated virus (AAV) vectors. The effects of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) combined with various electrolytes were evaluated using human plasma-derived IgG as a model protein. The HP-β-CD and L(+)-arginine hydrochloride combination synergistically increased the onset temperature of protein aggregation and inhibited the formation of soluble and insoluble aggregates during long-term storage. Notably, this synergistic effect was not observed when sucrose was used instead of HP-β-CD. Similar synergistic effects were observed with insulin and AAV vectors. The findings suggest that the stabilization mechanism could potentially involve enhanced interactions between HP-β-CD and IgG, preventing protein–protein interactions. However, the combination did not synergistically improve the solubility of free aromatic amino acids, including tyrosine and tryptophan. This study highlights the potential of using the combination of CDs and electrolytes as a promising formulation strategy for stabilizing complex protein therapeutics. However, further studies are needed to elucidate the underlying mechanisms and generalize the approach to other proteins with varying physicochemical properties.

Investigation of Metal–H2O Systems at Elevated Temperatures: Part I. Development of a Solubility Apparatus Specialized for Super-Ambient Conditions

Abstract Metals used in aqueous environments where high temperatures and pressures are present are susceptible to corrosion. This is the case for nuclear power plants, especially CANDUTM reactors, where the liquid water systems can reach over 300 °C at pressures well above 101.325 kPa (1 atm). In such situations, failure to control corrosion has economic and safety consequences. To extend corrosion modeling tools, such as Pourbaix diagrams, to harsh aqueous conditions, there is a need for experimental thermochemical data performed at elevated temperatures. This is particularly true for metal and alloy systems where such information is unavailable or unreliable. A relatively simple approach to obtaining temperature dependent thermodynamic properties is the investigation of solid–liquid phase, or solubility, equilibria. However, this requires specially designed instrumentation that can withstand harsh temperatures and extreme pH conditions, while providing accurate data. In this work, an apparatus developed for super-ambient highly acidic and alkaline solubility experiments is presented. Solubility measurements were made in the zinc oxide system, which has been extensively studied. Using these equilibrium data and comparing to the literature, allowed the instrumentation and analysis process to be validated. In situ pH measurements using a constant volume, batch reactor system are described along with a brief presentation of the ZnO dissolution equilibria results at 85 °C (358.15 K).

Porosity of green body: A potential essential factor regulating the making of sintered ceramsite from aluminum-based drinking water treatment residuals

Ceramsite is commonly applied in filtration systems for water treatment and aluminum (Al)-based drinking water treatment residue (DWTR) has been widely reported to have high potential to be recycled as main ingredient to make the sintered ceramsite. Various key factors affecting ceramsite making (e.g., composition and sintering temperature) have been identified to promote the beneficial recycling; however, according to sintering processes, this study hypothesized that porosity of green body was also a potential key factor, and then moisture content of green body (33 %-40 %) and particle size of DWTR (< 425 μm), which were the parameters initially considered for ceramsite making, were adopted to regulate the porosity for affecting characteristics and mechanisms investigation. The results verified the hypothesis and showed that increasing moisture content tended to decrease loss on ignition, apparent density, and bulk density, to increase water absorption, and to cause rougher surface of ceramsites, promoting the maximum Cu adsorption capacity of the ceramsite (estimated by Langmuir model); while at medium level of moisture content (e.g., 35 %), a relatively high compressive strength, strong Cu adsorbability (evaluated by Freundlich model), and low solubility in hydrochloric acid were found. Moreover, larger sized DWTR tended to increase loss on ignition, broken rate, solubility in hydrochloric acid, silt content, and water absorption, to reduce apparent density and compressive strength, and to cause rougher surface of the ceramsite, promoting the maximum adsorption capacity and decreasing the adsorbability of Cu. Further analysis suggested that moisture content was mainly through regulating total volume of voids and amount of raw materials to affect sintering, while particle size was mainly through regulating the contacting of particles. These results demonstrated the importance of the moisture contents of green body and the particle size of DWTR on affecting sintered ceramsite making, and porosity of green body was recommended to be taken as an essential factor when determining the optimal condition to make sintered ceramsite making.

Ultrasound and high-speed shear pretreatments of walnut meal protein: Structural and functional characterization and mechanistic investigation

The study aims to investigate the effect of the addition of ultrasound (US) with high-speed shear (HSS) at the extraction stage on the yield, physicochemical, structural, and functional properties of walnut meal protein (WMP). Compared with the conventional alkaline soluble acid precipitation method, the WMP yields after US and HSS pretreatments were increased by 1.11 and 1.21 times, respectively. Protein samples treated with the US showed increased surface hydrophobicity, a more uniform distribution of particle sizes, and greater contact angles. SDS-PAGE results showed that the protein had broken peptide bonds at higher molecular weights. The proteins' free sulfhydryl groups and fluorescence intensity have both increased as a result of the two pretreatment approaches, indicating a substantial alteration in the proteins' tertiary structure. Dynamic light scattering and SEM findings revealed that the US and HSS treatments improved the protein water solubility and emulsion stability by reducing the aggregate particle size and homogenizing the protein dispersion system. These results indicate that US and HSS pretreatment can effectively solubilize WMP polymers and enhance the structural function of the protein. This provides a theoretical basis for the application of WMP in food processing and offers a suitable technology for improving protein utilization.

Sinapic-Acid-Loaded Nanoparticles Optimized via Experimental Design Methods: Cytotoxic, Antiapoptotoic, Antiproliferative, and Antioxidant Activity.

Nanoparticles are frequently investigated as carrier systems that increase the biological activities of hydrophobic molecules, especially by providing them with water solubility. Sinapic acid (Sa), commonly found in plants, is a phenolic compound with a wide spectrum of biological activities and extensive pharmacological properties. The aim of this study was the synthesis/characterization of optimized sinapic-acid-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (SaNPs) to improve the solubility of sinapic acid (Sa) that limit its use in the biological system and investigate the biological activities of these nanoparticles in the breast cancer cell line. For this purpose, sinapic-acid-loaded PLGA nanoparticles were obtained and optimized by experimental design methods. Then, cytotoxic (MTT method), antiapoptotic (terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay), antiproliferative (immunocytochemically by PCNA assay), and antioxidant activities (superoxide dismutase (SOD) and catalase activities, glutathione, malondialdehyde (MDA), and caspase-3 levels) of optimized nanoparticles were examined comperatively with free drug on MCF-7 cells. The IC50 values of the SaNPs (170.6 ± 3.6 nm size) in MCF-7 cells were determined at 180, 168, and 145 μg/mL for 24, 48, and 72 h, respectively, and at these doses, the nanoparticles did not show any toxic effect on the MCF10A cell line. Treatment of Sa and SaNPs at doses of 24 and 48 h showed a statistically significant reduction in the PCNA level in MCF-7 cells, with an increase in the number of cells leading to apoptosis. In MCF-7 cells treated with SaNP at concentrations of 150 and 200 μg/mL for 24 h, MDA levels were significantly increased, SOD activities were significantly decreased, and reduced glutathione (GSH) and catalase levels were increased compared with control groups. The findings of this study indicate that polyphenolic compounds can contribute to the design of drugs for treatment by forming nanoparticle formulations. The developed nanoparticle formulation is thought to be a useful model for other hydrophobic biological active substances.

Physical and Functional Properties of Poly (Lactic Acid)/Paprika Oleoresin Films for Food Packaging Application

Background: Paprika oleoresin is a compound extracted from paprika, with functional properties, mainly due to its fatty acid composition and carotenoid profile. The effect of these compounds on PLA composite films has not been investigated. Objective: The objective of this study is to evaluate the effect of paprika oleoresin at different concentrations on the surface color, UV barrier, mechanical barrier, water vapor barrier, hydrophobicity, paprika oleoresin release and antibacterial properties of PLA-based composite films. Method: Functional poly(lactic acid)-based films incorporating paprika oleoresin extract (POE) at three levels (0.01%, 0.03% and 0.06%) were prepared using a solution casting method. Results: The paprika oleoresin showed an excellent compatibility with the PLA, as a uniform dispersion was observed. Moreover, the addition of POE improved properties such as elasticity (increase of 62%) and water vapor permeability (decrease of 69%). However, compared to the control film (polylactic acid), the solubility of the polylactic acid and paprika oleoresin extract films was found to be significantly increased. As the POE content increased, the color intensity of the PLA films became lighter orange-yellow. The film composed by PLA/ POE (0.06%) also presented significant bacterial inhibition for Staphylococcus aureus. In addition, the films demonstrated total carotenoid release in food-simulating liquids. Conclusion: Functional PLA/POE films can be a good alternative to replace traditional food packaging.

Latest Delivery Advancements of Lipid Nanoparticles for Cancer Treatment.

As one of the primary causes of illness and death globally, cancer demands novel and potent treatment approaches, which is why lipid nanoparticles (LNPs) have gained attention as a promising delivery system for anticancer drugs with precision and efficacy. The article discusses the salient characteristics of LNPs, such as the lipid components, particle size, polydispersity index, and encapsulation efficiency, followed by strategies that enhance their remarkable drug delivery capabilities. The articles explore LNPs ability to improve the solubility, stability, and bioavailability of various chemotherapeutics, nucleic acids, and immunotherapeutic modalities. It also highlights the recent advancement in surface modification of LNPs, which is essential to improve their effectiveness. Tailored coatings of LNPs improve targeting precision, stability, and biocompatibility; enhancing their transport to boost therapeutic efficacy for cancer targeting. The review summarizes the recent advancements made in using LNPs to treat different forms of cancer and focuses on the most recent clinical studies. Overall, the review highlights that the LNPs can target and treat cancer in a tailored manner through gene therapy, RNA interference, and immunotherapy.

Improving Water Solubility and Skin Penetration of Ursolic Acid through a Nanofiber Process to Achieve Better In Vitro Anti-Breast Cancer Activity.

Woman's breast cancer has always been among the top ten causes of cancer death, and nearly 2% to 5% of locally advanced breast cancers develop a fungating breast wound. Fungal breast cancer leads to skin ulcers, wound ruptures, and other bacterial infections in patients. Ursolic acid (UA), a natural pentacyclic triterpene compound, is widely distributed in many fruits. Previous studies demonstrated that UA has anti-breast cancer, antifungal, and improved wound-healing effects. UA, however, had poor water solubility and low bioavailability, restricting its clinical application. Nanofibers have the advantages of rapid dissolution, improved stability, and bioavailability of active ingredients. We had successfully prepared ursolic acid nanofibers (UANFs) and effectively improved their water solubility and skin penetration. UANFs can increase water solubility by improving the physicochemical properties, including increased surface area, intermolecular bonding with excipients, and amorphous transformation. Furthermore, UANFs had better anti-breast cancer activity than raw UA. UANFs inhibited the expression of phospho-signal transducer and activator of transcription 3 (STAT3) and phospho-extracellular regulated protein kinases (ERK)1/2, and induced cleaved caspase-3 protein expression, but had no effect on the raw UA treatment. In summary, UANFs enhanced the skin absorption of UA and improved its anti-breast cancer efficacy. We expect that UANFs can be used as an anti-breast cancer treatment and reduce the discomfort of breast cancer patients during dressing changes, but more detailed efficacy and safety trials still need to be conducted in further studies.

Exploring the potential of chlorogenic acid/chitosan nanoparticle-loaded edible films with photodynamic technology for Mongolian cheese application

This study aimed to evaluate the efficiency of edible films made from chlorogenic acid/chitosan (CGA/CS) nanoparticles combined with photodynamic technology (PDT). Hydroxypropyl starch (HS) and κ-carrageenan (KC) were used as the main ingredients in the preservation of Mongolian cheese under the PDT condition. The mechanical characteristics, water vapor adsorption, solubility, permeability, and release of chlorogenic acid in aqueous media were evaluated. The incorporation of CGA/CS significantly enhanced the tensile strength and barrier characteristics of the edible films. The antimicrobial efficacy of the edible film was assessed over a period of 7 days while the cheese was being stored, followed by PDT application. The use of antimicrobial PDT did not cause lipid oxidation in cheese samples. Additionally, the combination of CGA/CS@HS/KC helped to reduce fat oxidation in Mongolian cheese. Utilizing an edible film in conjunction with PDT presents a viable solution for prolonging the shelf life of Mongolian cheese while maintaining its sensory attributes and nutritional qualities.

Formulation and evaluation of salicylic acid hydrogel based on hydrotropic solubility enhancement technique

Background and objective: Salicylic acid (SA) has keratolytic activities and it is used topically to treat dandruff and seborrheic dermatitis. The hydrotropic phenomenon in pharmaceutical preparations is utilized to enhance the solubility of water-insoluble drug molecules that promoted to prepare the salicylic acid as a hair gel for local effect and it can extend its keratolytic action for a longer period compared to the salicylic acid solution. Methods: Preformulation study was performed to exclude any unwanted chemical interaction between SA and excipients using Fourier-transform infrared spectroscopy (FTIR). The solubility of SA was determined separately in sodium acetate and sodium citrate solutions at a concentration of 1, 3, and 5 %w/v, using distilled water as a solvent. An optimum gel formulation was developed and it was used to prepare the SA gel formulation. Characterizations were performed in terms of physical appearance, viscosity, pH, and spreadability, in-vitro studies were performed in physiological pH, and ex-vivo diffusion studies were performed utilizing rats’ skin. Results: FTIR did not show any chemical interaction between the drug and sodium citrate. The hydrotropic solution of sodium citrate with a concentration of 5% w/v increased the solubility of SA by 28 folds, while the sodium acetate solutions with a concentration of 5% w/v increased the solubility of SA by 19 folds. The optimum gel formula (F1) with a drug content of 97% showed a slow dissolution rate and minimum diffusion through the skin. Conclusion: The hydrotropic solubilization technique significantly influenced the solubilization of salicylic acid in the water and the highest solubility rate was achieved from 5% w/v sodium citrate solution. The formulated hydrogels using carbopol 971P as gelling agent decreased the diffusion rate of SA.

Preparation and Performance Evaluation of a Supramolecular Polymer Gel-Based Temporary Plugging Agent for Heavy Oil Reservoir.

When encountering heavy oil reservoirs during drilling, due to the change in pressure difference inside the well, heavy oil will invade the drilling fluid, and drilling fluid will spill into the reservoir along the formation fractures, affecting the drilling process. A supramolecular polymer gel-based temporary plugging agent was prepared using acrylamide (AM), butyl acrylate (BA), and styrene (ST) as reacting monomers, N, N-methylenebisacrylamide (MBA) as a crosslinking agent, ammonium persulfate (APS) as an initiator, and poly(vinyl alcohol) (PVA) as a non-covalent component. A supermolecular polymer gel with a temperature tolerance of 120 °C and acid solubility of 90% was developed. The experimental results demonstrated that a mechanically robust, thermally stable supramolecular polymer gel was successfully synthesized through the copolymerization of AM, BA, and ST, as well as the in situ formation hydrogen bonding between poly (AM-co-BA-co-ST) and PVA, leading to a three-dimensional entangled structure. The gel-forming solution possessed excellent gelling performance even in the presence of a high content of salt and heavy oil, demonstrating superior resistance to salt and heavy oil under harsh reservoir conditions. High-temperature and high-pressure plugging displacement experiments proved that the supramolecular polymer gel exhibited high pressure-bearing capacity, and the blocking strength reached 5.96 MPa in a wedge-shaped fracture with a length of 30 cm. Furthermore, the dissolution rate of the supramolecular polymer gel was as high as 96.2% at 120 °C for 48 h under a 15% HCl solution condition.

Transformation of typical heavy metals during preparation of porous carbon from coal gasification fine slag

To clarify the fate of typical heavy metals during preparation process of porous carbon, we produced porous carbon using a two-step strategy and investigated the transformation behavior of heavy metals including V, Cr, Mn, Cu, Zn and Ba in the process. A modified Community Bureau of Reference (BCR) sequential extraction procedure was implemented to reveal the occurrence state of heavy metals. The results clearly showed that the transformation of selected heavy metals in activated carbon was mostly determined by the occurrence state, volatile nature and operating procedure. In addition to the new aluminosilicate minerals, abundant pore structure also had evident dependence on solidifying heavy metals in porous carbon. The content of heavy metals in activated carbon were considerably lower than YKFS, and V, Cr and Cu were more accumulated in porous carbon. It is also important to note that Zn possessed markedly lower content and REI value (3.61–56.17 %) in activated carbon and porous carbon owning to the volatile nature of Zn and acid solubility of Zn-base minerals. The Risk Assessment Code (RAC) evaluation conducted that the acid leaching operation effectively decreased the hazardous properties of heavy metals. The research results can provide significant guidance for value-added utilization of gasification fine slag in an environmentally friendly.

Tuning Ferulic Acid Solubility in Choline-Chloride- and Betaine-Based Deep Eutectic Solvents: Experimental Determination and Machine Learning Modeling.

Deep eutectic solvents (DES) represent a promising class of green solvents, offering particular utility in the extraction and development of new formulations of natural compounds such as ferulic acid (FA). The experimental phase of the study undertook a systematic investigation of the solubility of FA in DES, comprising choline chloride or betaine as hydrogen bond acceptors and six different polyols as hydrogen bond donors. The results demonstrated that solvents based on choline chloride were more effective than those based on betaine. The optimal ratio of hydrogen bond acceptors to donors was found to be 1:2 molar. The addition of water to the DES resulted in a notable enhancement in the solubility of FA. Among the polyols tested, triethylene glycol was the most effective. Hence, DES composed of choline chloride and triethylene glycol (TEG) (1:2) with added water in a 0.3 molar ration is suggested as an efficient alternative to traditional organic solvents like DMSO. In the second part of this report, the affinities of FA in saturated solutions were computed for solute-solute and all solute-solvent pairs. It was found that self-association of FA leads to a cyclic structure of the C28 type, common among carboxylic acids, which is the strongest type of FA affinity. On the other hand, among all hetero-molecular bi-complexes, the most stable is the FA-TEG pair, which is an interesting congruency with the high solubility of FA in TEG containing liquids. Finally, this work combined COSMO-RS modeling with machine learning for the development of a model predicting ferulic acid solubility in a wide range of solvents, including not only DES but also classical neat and binary mixtures. A machine learning protocol developed a highly accurate model for predicting FA solubility, significantly outperforming the COSMO-RS approach. Based on the obtained results, it is recommended to use the support vector regressor (SVR) for screening new dissolution media as it is not only accurate but also has sound generalization to new systems.

Plasma Jet Mediated Reduction of Metal Salt

We demonstrate electrodeposition where the plasma acts as both an electrolyte and electrode, to deposit metallic conductive coatings. In conventional electroplating metal ions are reduced at a working electrode with an applied electrochemical potential. Here an RF atmospheric pressure plasma jet (APPJ) is able to induce a electrochemical reduction due to the presence of free electrons. The advantage of this method is demonstrated by the ability to deposit conducting metal tracks on delicate surfaces including insulators and polymers. The small size and gaseous nature of the plasma allows deposition in difficult geometries with precise spatial control.The reduction process occurs within the plasma. As the aerosolized metal salt crystals interact with the plasma, the free electrons reduce the metal and the hydrogen combines with the anion producing a water soluble acid. The metal reduction takes place within the plasma jet, as show by varying the plasma power and determining the amount of zerovalent metal deposited. Even at low powers, <6 W, the plasma was able to fully reduce the silver, however the copper requires plasma powers of 12 W and above in order to be fully reduced. Once reduced the deposited tracks were shown to be conductive with around 20 % and around 5 % of bulk conductivity for silver and copper respectively. A sintering process occurs also within the plasma, leaving a contiguous track of fused particles of zerovalent metal producing the conducting tracks. The technique is demonstrated mainly for copper and silver, however multiple other metals were capable of being deposited. In addition to the conductivity, the track adherence was tested both using a Scotch Tape© pull test and an in-house constructed scratch test. The track was completely unaffected by the tape pull and the stylus type scratch test showed that the films were scratch resistant up to a pressure up to of 420 kg cm-2, with no measurable drop in conductivity.The APPJ is an accessible, low power, sustainable, precise electroplating device, capable of depositing pure metallic films onto a variety of surfaces. Furthermore, we demonstrate deposition on rough surfaces such as damaged fiberglass, as well as sensitive surfaces including plant tissue and pigskin, with limited damage to the surface.Figure 1. a) showing the deposition setup including nebuliser, salt solution injection, gas flow and power supply. An optical image of the APPJ during deposition operation is included, as well as Schlieren imagine showing the laminar gas flow. b) A silver Hilbert curve printed onto Kapton 0.05 mm thickness via the plasma deposition technique, in a single step process, with no sample prep or post processing. c) Copper deposited on porcine skin showing conductance as part of a LED circuit. Figure 1

Effect of Dry Processing of Coconut Oil on the Structure and Physicochemical Properties of Coconut Isolate Proteins.

The effects of the dry processing of coconut oil on the amino acid composition, molecular weight, secondary structure, solubility, surface hydrophobicity, microstructure, total sulfhydryl and free sulfhydryl content, free amino acid content, thermal properties, and water-holding, oil-holding, foaming, and emulsifying properties of coconut isolate protein were investigated. The results showed that the dry processing altered the amino acid composition of coconut isolate proteins as well as resulted in fewer irregular structural regions and more homogeneous particle sizes, leading to an improvement in the thermal stability of the proteins. SDS-PAGE analysis showed that globular proteins located at ~34 kDa in coconut isolate proteins underwent slight degradation during the dry processing of coconut oil. The dry processing reduced the surface hydrophobicity, total and free sulfhydryl groups, solubility, and free amino acid content of coconut isolate proteins. In addition, the water-holding capacity, oil-holding capacity, and foam stability of coconut isolate proteins were improved to different degrees after the dry processing. Therefore, the development and utilization of copra meal protein is of great significance to increase its added value.