Xanthan Research Articles

Surfactant-Free w/o Gelled Emulsions with Benzyl Alcohol: Analytical Study for Varnish Removal on Oil Paintings

In this study, the use of surfactant-free water-in-oil gelled emulsions containing benzyl alcohol (BAl/w) is proposed as an alternative to the more traditional use of organic solvents for removing varnishes. To mitigate the strong swelling and solvent action of benzyl alcohol and protect the paint and the underlying layers, temporary hydrophobization with cyclomethicone D5 has been proposed. The aim of this study was to evaluate the application of BAl/w surfactant-free, constructed with three different gelling agents of the aqueous dispersing phase (xanthan gum, agar-agar, and polyacrylate) on the surface of an oil painting varnished with and without preliminary saturation with D5. The role of pH, which can influence the ionization, and therefore the water solubility of terpene molecules and all other acid species present on the surface, was also studied. Fourier transform infrared (FT-IR) and Raman spectroscopies were used to characterize the pigments and the surface before and after varnish removal. Elemental analysis and any morphological changes were evaluated using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS). The leaching efficiency of each surfactant-free emulsion applied on the paint surface was evaluated using a gas chromatography/mass spectroscopy (GC/MS) analysis: the fatty acid content was established in each sample before and after the treatments.

Natural Macromolecule-Based Lubricative Catheter Coatings with Sustained Adaptive Antibacterial Property for Encrustation and Infection Prevention.

Catheter-associated urinary tract infection (CAUTI) are a global health burden. Moreover, the friction during urinary catheter placement also induces pain in patients. Therefore, there is a pressing need to develop effective antibacterial and lubricative coatings on the surface of urinary catheter. In this work, a facile volatilization film-forming method is used to construct coatings on catheter surfaces. Xanthan gum (SR), which has good lubricative and antifouling properties, is oxidized to cross-link with multi-amino compounds, gentamicin (GS), and gelatin, to fabricate uniform coatings on silicone catheters (SR-GXGs). The structures of SR-GXGs are regulated by the components of the film formation solutions. The bacterial metabolism can produce an acidic micro-environment that can regulate GS release to achieve on-demand administration. SR-GXG2 can eliminate 99.99% of common pathogenic bacteria and reduce the dynamic friction coefficient by 98.73%, and showed high stability in a 7-day flowing experiment. In addition, the universality of this method is demonstrated on various kinds of matrices with different shapes, including commercial urethral catheters. In vivo, SR-GXG2can effectively avoid urinary tract injury and encrustation phenomenon because of its good anti-infection, antifouling, and lubricative properties. This work provides a promising strategy for developing multifunctional antibacterial coatings on medical catheters.

Solute Energetics in Aqueous Xanthan Gum Solutions: What Can Be Learned from a Fluorescent Probe?

Xanthan gum (XG) is a well-known anionic polysaccharide that finds broad application in the food and petroleum industries because of its ability to enhance solution viscosity at low concentrations and moderate temperatures. The aim of this work was to use the solvation probe coumarin 153 (C153) to characterize changes in the xanthan gum (XG) solution microstructure as a function of XG concentration and temperature from the perspective of a dissolved solute molecule. We established the utility of C153 fluorescence to track solution changes for XG concentrations that span the transition region from a dilute to a semi-dilute solution, defined by the xanthan gum overlap concentration, C*~0.02 g/dL. The temperature was varied from 293 to 353 K to probe solution conditions wherein XG has been reported to undergo a structural change from helix to random coil conformation, the details of which are still under debate. While C153 fluorescence does not elucidate direct structural information, the emission response is a simple means by which changes in aqueous XG solution can be identified. C153 spectroscopy is observed to correlate with XG conformational changes, as reported in the literature.

Enhancing stability and physiological activity of Aronia melanocarpa L. anthocyanin by polysaccharides.

The existence of multiple phenolic hydroxyl groups in anthocyanins makes their structure unstable and leads to the degradation of anthocyanins. At present, there are few studies on the stability and physiological activity of Aronia melanocarpa L. anthocyanins by different polysaccharides. The present study investigated the effects of carboxymethyl cellulose (CMC), pectin and xanthan gum (XG) on the stability and biological activities of A. melanocarpa L. anthocyanins. The anthocyanins of A. melanocarpa L. (AAM) were successfully extracted from A. melanocarpa L. with an extraction rate of 3.07 mg g-1 by single factor and response surface experiments. The results of scanning electron microscopy and a multispectral technique showed that AAM-polysaccharides complex was combined by hydrogen bond, cation-π interaction and electrostatic interaction. The AAM-polysaccharides complex improved the retention rate of anthocyanins after treatment with light, heating, oxidant reducing agent, metal ions and preservatives compared to the results for AAM alone. Determination of DPPH· scavenging capacity, ABTS+ scavenging capacity and total reducing capacity indicated that the presence of polysaccharide could improve the antioxidant activity of AAM in vitro. The three polysaccharides combined with AAM showed higher binding ability to taurocholate and glycocholate compared to the AAM group, with the AAM-XG binding rate being the highest at 27.61% and 20.61%, respectively. The tyrosinase inhibition rate significantly increased with the incorporation of XG, reaching 72.22%. The stability and physiological activity of AAM were improved after the addition of CMC, pectin and XG in the simulated system, and the presence of XG showed greater advantages. The present study strongly suggests that anthocyanins driven by polysaccharides have a positive effect on the stability and physiological activity of anthocyanins and may also provide a research basis for the development of processing technology for anthocyanins in food. © 2024 Society of Chemical Industry.

Detecting N-Phenyl-2-Naphthylamine, L-Arabinose, D-Mannose, L-Phenylalanine, L-Methionine, and D-Trehalose via Photocurrent Measurement

The concentration of small molecules reflects the normality of physiological processes in the human body, making the development of simple and efficient detection equipment essential. In this work, inspired by a facile strategy in point-of-care detection, two devices were fabricated to detect small molecules via photocurrent measurement. A linear response of the photocurrent against the concentration of the small molecules was found. In the first device, metal ions were introduced into gel substrates made by xanthan gum to enhance photocurrent response. N-phenyl-2-naphthylamine was measured when iron or manganese ions were used. L-Phenylalanine was measured when the gel was modified by samarium, iron, cerium, or ytterbium ions. L-(+)-Arabinose was detected via the gels modified by iron or holmium ions. D-(+)-Mannose was detected when the gel was modified by ytterbium, manganese, chromium, or sodium ions. L-Methionine was detected in the gels modified by samarium, zinc, or chromium ions. The second device was based on a paper sheet. A sugar-like molecule was first synthesized, which was then used to modify the paper. The detection was possible since the photocurrent showed a linear trend against the concentration of D-Trehalose. A linear fit was conducted to derive the sensitivity, whose value was found to be 5542.4. This work offers a novel, simple, and environmentally sustainable platform that is potentially useful in remote areas lacking medical devices.

The Effect of Polymer Amendment on the Colloidal Properties of a Waste K<sup>+</sup>- Rich Bentonite for Water-Based Drilling Fluid Applications

This research is concerned with the investigation of waste bentonite produced from a quarry in Cyprus, after being polymer-amended for use as a low-density solid additive in water-based drilling fluid systems (WBFS). According to API procedures, the waste bentonite samples are mechanically processed to a size < 63 μm and then activated with soda ash under “wet & thermal” conditions. The activated material is then used in the blending of actual WBF drilling fluid systems amended with polymers to obtain the desired colloidal properties because bentonite alone was not sufficient. For this procedure, three anionic polymers, Xanthan gum, CMC, and PAC-R were considered because they are very common as drilling fluid additives and under certain concentrations can help reach the desired colloidal properties of the WBFS. Results from this work show that minor polymer addition of all three polymers assists the waste material in reaching excellent filtration control qualifying the waste material according to API. Repurposing local waste clay material for drilling applications serves as a cost-effective solution leading to the management of local resources and aligning with environmental sustainability thus contributing to the circular economy principle.

A low-cost, open-source cylindrical Couette rheometer

Rheology describes the flow of fluids from food and plastics, to coatings, adhesives, and 3D printing inks, and is commonly denoted by viscosity alone as a simplification. While viscometers adequately probe Newtonian (constant) viscosity, most fluids have complex viscosity, requiring tests over multiple shear rates, and transient measurements. As a result, rheometers are typically large, expensive, and require additional infrastructure (e.g., gas lines), rendering them inaccessible for regular use by many individuals, small organizations, and educators. Here, we introduce a low-cost (under USD$200 bill of materials) Open Source Rheometer (OSR), constructed entirely from thermoplastic 3D printed components and off-the-shelf electromechanical components. A sample fluid rests in a cup while a micro stepping motor rotates a tool inside the cup, applying strain-controlled shear flow. A loadcell measures reaction torque exerted on the cup, and viscosity is calculated. To establish the measurement range, the viscosity of four Newtonian samples of 0.1–10 Pa.s were measured with the OSR and compared to benchmark values from a laboratory rheometer, showing under 23% error. Building on this, flow curves of three complex fluids – a microgel (hand sanitizer), foam (Gillette), and biopolymer solution (1% Xanthan Gum) – were measured with a similar error range. Stress relaxation, a transient test, was demonstrated on the biopolymer solution to extract the nonlinear damping function. We finally include detailed exposition of measurement windows, sources of error, and future design suggestions. The OSR cost is ∼1/25th that of commercially available devices with comparable minimum torque (200 µN.m), and provides a fully open-source platform for further innovation in customized rheometry.

Supersaturation Behavior: Investigation of Polymers Impact on Nucleation Kinetic Profile for Rationalizing the Polymeric Precipitation Inhibitors.

Although nucleation kinetic data is quite important for the concept of supersaturation behavior, its part in rationalizing the crystallization inhibitor has not been well understood. This study aimed to investigate the nucleation kinetic profile of Dextromethorphan HBr (as an ideal drug, BCS-II) by measuring liquid-liquid phase segregation, nucleation induction time, and Metastable Zone width. Surfeit action was examined by a superfluity assay of the drug. The concentration was scrutinized by light scattering techniques (UV spectrum (novel method) and Fluorometer (CL 53)). The drug induction time was 20 min without polymer and 90 and 110 min with polymers, such as HPMC K15M and Xanthan Gum, respectively. Therefore, the order of the polymer's ability to inhibit nucleation was Xanthan Gum > HPMC K15M in the medium (7.4 pH). Similarly, the drug induction time was 30 min without polymer and 20, 110, and 90 min with polymers, such as Sodium CMC, HPMC K15M, and Xanthan Gum, respectively. Therefore, the order of the polymer's ability to inhibit nucleation was HPMC K15M > Xanthan Gum > Sodium CMC in SIFsp (6.8 pH), which synchronizes the polymer's potentiality to interdict the drug precipitation. The HPMC K15M and xanthan Gum showed the best crystallization inhibitor effect for the maintenance of superfluity conditions till the drug absorption time. The xanthan gum is based on the "glider" concept, and this shows the novelty of this preliminary research. The screening methodology used for rationalizing the best polymers used in the superfluity formulations development successfully.

Utilisation of Class-F fly ash in xanthan gum–amended neutral or acidic soils

Xanthan gum (XG) is an eco-friendly biopolymer with potential applications in soil amendment. However, in acidic soil environments, the pyruvate groups and glycosidic bonds in XG molecules tend to hydrolyse, thereby weakening the efficacy of soil improvement. In this study, the feasibility of utilising alkaline Class-F fly ash (FA) to assist XG in reinforcing acidic soils was evaluated through proctor compaction, unconfined compression, and one-dimensional consolidation. With the increasing soil acidities, the beneficial effect of FA on the geotechnical performances of XG-amended soils grew. The improvement in both mechanical strength and compressibility of XG-amended acidic soils might be caused by the crossing-linking of XG molecular strands and the mitigated hydrolysis of XG hydrogels due to the presence of FA. Based on the findings, it is suggested to use FA in combination with XG for treating the acidic soils and use XG alone for treating the neutral soils. The research outcomes will promote the reuse of solid waste Class-F FA in sustainable geotechnical engineering practices, for example, biopolymer-based soil amendment in acidic soils.

Regulating the space charge at interface by negative polar biomolecule enabling ultrastable Zn anode chemistry

The irreversibility of Zn metal anode arising from uncontrollable dendrite growth and hydrogen evolution reaction, especially at high current densities, has challenged the commercialization application of aqueous Zn-ion batteries. Here we report biomolecule additive, named xanthan gum, to solve these issues through making use of dissociated electronegative groups to reduce space charge near the anode-electrolyte interface, tuning solvation structure and form H2O-poor electrical double layer to regulate the Zn deposition behaviors. Meanwhile, the dissolved xanthan gum with multiple polar groups can break the association between H2O and Zn2+ to reconstruct solvated structures of Zn ions to suppress hydrogen evolution reaction (HER). Therefore, the Zn//Zn symmetric cells in ZnSO4 electrolyte with xanthan gum deliver an ultra-long cycle life (>4700 h), and also present excellent cycling performances in other electrolytes (Zn(OAc)2 and Zn(OTf)2). More importantly, a high coulombic efficiency of 99.7 % is achieved using Zn//Cu half cells tested and excellent cycling life for KVO//Zn full cells. This work provides a guidance to design the electrolyte additive for highly reversible Zn metal batteries.

Effects of hydrocolloids on the structure and physicochemical properties of triticale starch during fermentation

The regulation of the structure and properties of new starch varieties has been a necessary step in the development of promising products. This study investigated the effects of 1 % xanthan gum (XG) and hydroxypropyl methylcellulose (HPMC) on the physicochemical properties and structure of triticale starch during fermentation. Frequency scanning and rapid viscosity analyzer results showed that the addition of XG or HPMC during fermentation resulted in the reduced loss factor (tanθ) and the increased peak viscosity, indicating that the network gel strength is enhanced. X-ray diffraction and attenuated total reflectance Fourier transform infrared spectroscopy experimental results revealed that adding XG or HPMC in the triticale starch during fermentation increased relative crystallinity (2.7 % and 5.27 %, respectively) and short-range order. Combined with microstructure and thermal analysis, the encapsulation effect of XG or HPMC on triticale starch increased the thermal stability of triticale starch during fermentation, which was specifically reflected by higher residue content (26.69 % and 19.13 %, respectively). This study can provide a theoretical basis for the effect of hydrocolloids on the texture and digestibility of triticale starch fermented products.

Impact of foam-mat drying conditions of “Gấc” aril on drying rate and bioactive compounds: Optimization by novel statistical approaches

This study was conducted to optimize the foam-mat drying conditions to maximize quality [β-carotene and total polyphenol content (TPC)] and drying rate of “Gấc” aril powder by using two novel statistical techniques as Response Surface Methodology (RSM) and Artificial Neural Network (ANN) couple with Genetic Algorithm (GA). During production process, level of egg albumin (EA) used for foaming process and drying temperature mainly influenced the drying rate and content of antioxidant compounds in powder. ANN model of 3–10-3 showed more accuracy and faster prediction capacity than RSM model did. ANN-GA model predicted the optimal conditions to be 13.31 % EA, 0.26 % xanthan gum and drying temperature of 73.1 °C, with the drying rate of 1.89 g-water/g-dry matter/min, β-carotene content of 395.88 μg/g, TPC of 1.68 mgGAE/g. These results confirmed the suitability and promising of foam-mat drying for “Gấc” aril powder production, to be producing food ingredient containing highly bioactive compounds.

Preparation and properties of a fluorine-free aerogel foam extinguishing agent

Research on fluorine-free firefighting foams is urgently needed due to the environmental hazards of conventional aqueous film-forming foams. Functional particles have significant research potential in the development of fluorine-free foam extinguishing agents. In this study, hydrophobic aerogel particles were prepared using a template method, and a fluorine-free aerogel foam extinguishing agent was developed by electrostatic and steric stabilization. The research investigated the impact of aerogel particles and polymers (xanthan gum and polyethylene glycol) on foam characteristics, fire extinguishing performance, as well as their synergistic effect. The results indicated that polymers and aerogel particles reduced the average foam radius and enhanced the foam liquid film strength, though they could not inhibit foam coarsening. Although accelerating foam drainage, aerogel particles effectively enhanced the fire extinguishing performance of the foam. With the addition of only 0.4wt.% aerogel particles, the fire extinguishing time of the foam was reduced by 21.7%, while 100% burnback time increased by 45%. Furthermore, the polymer enhanced the burnback performance of the foam in synergy with aerogel particles by improving foam stability on the hot heptane surface.

Preparation and characterization of a low viscosity spray dust suppressant based on xanthan gum grafted sodium α-olefin sulfonate copolymer with proactive coal-adhesive and surface-active properties

To address the problem of the high viscosity of current composite dust suppressants, which results in spray droplet sizes that are not optimal for capturing respirable dust, a low viscosity, proactive coal-adhesive, long-lasting spray dust suppressant, XG-AOS/Tre, has been developed. The suppressant utilizes xanthan gum (XG) from microbial fermentation, with α-olefin sulfonate grafted onto its hydroxyl groups to form a copolymer (XG-AOS), reducing its viscosity while maintaining the surface activity of the hydrocarbon chain and its affinity for coal dust. It has a weighted average molecular weight of 398341, a surface tension of 26.1 mN/m, a viscosity of 1.59 mPa·s, and a contact angle of 48° with coal cake. The suppressant achieves a total dust suppression rate of 85.7 % and a respirable dust suppression rate of 85.9 %. Because of its surface activity and high molecular weight, it efficiently wets and settles coal dust. It retains 47.3 % of the water in its solution 24 h after being sprayed and forms an adhesive film upon complete evaporation, providing the coal dust with resistance to wind erosion. The dust suppressant improves the dust suppression rate for dust control in coal mining. Its properties contribute to the sustainable development and environmental protection of the coal industry.

Developing a novel artificial model to predict the foaming properties and β-carotene content of lucuma (Pouteria lucuma) during foam-mat drying and process optimization

Drying fruit puree by the foam drying method has become popular due to its simplicity, low cost, short drying time, and low thermal degradation. The objective of the study was to investigate the effect of foaming conditions on foam properties (foam expansion, foam density) and content of β-carotene in lucuma powder using Box-Behnken design (BBD) with 3 factors and 3 levels, including water:lucuma ratio (1:1–3:1), egg albumin concentration (EA, 5–15%), and xanthan gum (XG, 0.1–0.3%). Response surface methodology (RSM) and artificial neural network (ANN) were used for model establishment. The results showed that as the EA increased, the foam volume increased significantly, while the foam density decreased. The ANN-coupled BBD model structure of 3-10-3 demonstrated a high level of accuracy in predicting the impact of foaming formulation on responses, with a coefficient of determination exceeding 0.99. The optimal conditions by stimulation multiple-objective RSM for lucuma foam-mat drying were achieved with a water:lucuma ratio, EA, and XG of 2.53:1, 10.8%, and 0.22%, respectively. Based on these ideal conditions, the foam density, foam expansion, and β-carotene content of the dried powder were found to be 0.23±0.04 g/mL, 228±2%, and 237.1±0.1 μg/g, respectively. The obtained experimental values were very close to the model-predicted results, with very low differences identified when the validation was performed. These findings provide information for controlling the drying process using an artificial model and further applying lucuma powder in various fields in the food industry.

Extraction and characterization of Plantago major L. mucilage as a potential natural alternative over synthetic polymers for pharmaceutical formulations

The growing demand for natural cosmetic ingredients with minimal environmental impact has spurred the search for novel alternatives to synthetic materials. In this context, mucilage from Plantago major L., an exotic plant widely spread in Brazil, presents a promising option. This study focused on optimizing mucilage extraction from Plantago major L. seeds, drying the extracted solution, characterizing the dried product, and evaluating its rheological properties for potential cosmetic use. An extraction procedure was developed using a baffled-jacketed stirred vessel with the addition of Teflon® particles to improve seed attrition and enhance seeds’ mucilage removal. The mucilage solution was filtered, precipitated by ethanol addition, and then dried on various surfaces, with Teflon® proving the most effective. The product’s suitability was evaluated in gel formulations and compared with established commercial polymers. The results showed an optimum extraction yield of 18.4% from the seeds, at the optimum extraction conditions of 140.5 minutes, solvent-to-seed mass ratio of 0.0284, and a temperature of 80.2 °C. The dried purified mucilage yielded a thermally stable product up to 300°C, with a structure featuring the fingerprint region between 800 and 1200 cm⁻1, characteristic of carbohydrates. The gel formulation obtained with the product exhibited a non-Newtonian, pseudoplastic rheological profile, resembling the ones prepared with the natural and semi-synthetic polymers such as xanthan gum and hydroxyethyl cellulose, commonly used in cosmetic formulations. This study highlights the potential of mucilage from Plantago major L. seeds for applications in pharmaceutical formulations.

Experimental investigation on the sealing of flowing seawater by xanthan gum composite cement‑sodium silicate slurry in single fracture

Experimental investigation on the sealing of flowing seawater by xanthan gum composite cement‑sodium silicate slurry in single fracture

Formulation and evaluation of sustained release matrix tablet of ketoprofen

The aim of the study was the formulation of the sustained release matrix tablet of Ketoprofen. The sustained release tablet was prepared by wet-granulation method. The tablets were formulated using hydrophilic polymer HPMC K4M and xanthan gum. Preformulation compatibility studies indicate that there is no interaction between the excipient and the drug. Total seven batches were prepared and powder blends before compression was subjected for evaluation of flow properties. All the parameter was found to be within the limit showing good flow property. After compression, the entire tablet batch was evaluated for thickness, hardness, friability, weight variation, drug content uniformity, swelling index, In-vitro release pattern. The thickness of tablet indicates that die fill was uniform in all the formulation and the formulation possessed sufficient hardness & friability indicating a good mechanical strength of the development formulation. The weight of the all the formulation were found to be with in pharmacopeial limit. The In-Vitro dissolution profile of all the formulation of Ketoprofen was controlled over an extended period of time. The optimized formulation of F7 containing combination of HPMC K4M and xanthan gum was consider as the best formulation with respect to its sustained in vitro drug release for 12 hrs, total sustained release time & improved bioavailability. The developed formulation was found to be stable during the stability studies of 3 month indicating good stability of the tablets.

Design and development of minoxidil-loaded nano carrier-based transdermal gel of trans-ethosomes for transdermal delivery system: Invitro evaluation studies

The present aim of the study was to develop a transdermal drug delivery system of the Nano-carrier-based Minoxidil-loaded transethosomal gel. In this study, we used Soyaphopshotidylcholine as a vesicle-forming agent and Sodium deoxycholate as a surfactant, and vesicle stabilizer as excipients. The Minoxidil transethosomes were prepared by thin film hydration technique. The prepared Minoxidil-loaded transethosomes (MTE) were evaluated and the particle size (189.83nm and 206.18nm), PDI(0.292 and 0.263), Zeta potential(-29.1mv and-28.2mv) and the entrapment efficiency (89.16±3.16 and 81.65±2.74) of MTE5 and MTE6. The MTE dispersion was further used to prepare gel, the gel base was prepared by using Carbopol, Xanthan gum, and HPMC K15. The optimized MTE-gel formulation was further evaluated, and the cumulative percentage of drug release was 98%, the 3 months stability studies show satisfactory results indicating good gel stability.

Curdlan/xanthan gum-based composite hydrogel with near-infrared irradiation responsive properties for infected wounds healing

Open wounds are prone to bacterial contamination and delayed healing due to environmental exposure, necessitating the development of advanced wound dressings. Hydrogels are ideal candidates for wound care for maintaining a moist environment which benefits for the cell migration and tissue regeneration. However, conventional polysaccharide hydrogels lack intrinsic antibacterial properties, prompting the incorporation of antibacterial agents. Herein, we present a novel composite hydrogel synthesized from curdlan (CUR) and xanthan gum (XG) via thermal annealing, augmented with MXene and Mg2+ to enhance antibacterial efficacy and promote cellular migration. The results proved that the mechanical properties of the composite hydrogel prepared with CUR and XG are significantly enhanced. Due to the influence of near-infrared irradiation, the antibacterial rates of XC/Mg2+/MX against S. aureus and P. aeruginosa are 81.84 % and 89.27 %, respectively. This innovative composite hydrogel offers new insights and avenues in the progress of sophisticated wound healing dressings areas.