Beatriz Ribeiro Souza de Azevedo, B. G. Alvarenga, A. M. Percebom, A. Pérez-Gramatges
{"title":"Interplay of Interfacial and Rheological Properties on Drainage Reduction in CO2 Foam Stabilised by Surfactant/Nanoparticle Mixtures in Brine","authors":"Beatriz Ribeiro Souza de Azevedo, B. G. Alvarenga, A. M. Percebom, A. Pérez-Gramatges","doi":"10.3390/colloids7010002","DOIUrl":"https://doi.org/10.3390/colloids7010002","url":null,"abstract":"Although nanoparticles (NPs) are known to increase foam stability, foam stabilisation is not observed in all surfactant/NP combinations. The present study evaluates the stability of CO2 foams containing surfactant/NP mixtures with attractive or repulsive electrostatic interactions at the low pH imposed by CO2 in the presence of a high-salinity brine. Three ionic surfactants and two oxide NPs (SiO2 and Al2O3) were used in combinations of similar or opposite charges. Surface tension, viscosity, ζ-potential and hydrodynamic size experiments allowed the analysis of CO2 foam stability based on the impact of surfactant–NP interactions on bulk and interfacial properties. All oppositely charged systems improved the foam half-life; however, a higher NP concentration was required to observe a significant effect when more efficient surfactants were present. Both bulk viscosity and rigidity of the interfacial films drastically increased in these systems, reducing foam drainage. The mixture of SiO2 with a zwitterionic surfactant showed the greatest increase in CO2 foam stability owing to the synergy of these effects, mediated by attractive interactions. This study showed that the use of NPs should be tailored to the surfactant of choice to achieve an interplay of interfacial and rheological properties able to reduce foam drainage in applications involving CO2 foam in brine.","PeriodicalId":10433,"journal":{"name":"Colloids and Interfaces","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46724113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Salum, Çağla Ulubaş, O. Güven, L. Y. Aydemir, Z. Erbay
{"title":"Casein-Hydrolysate-Loaded W/O Emulsion Preparation as the Primary Emulsion of Double Emulsions: Effects of Varied Phase Fractions, Emulsifier Types, and Concentrations","authors":"P. Salum, Çağla Ulubaş, O. Güven, L. Y. Aydemir, Z. Erbay","doi":"10.3390/colloids7010001","DOIUrl":"https://doi.org/10.3390/colloids7010001","url":null,"abstract":"Stable primary emulsion formation in which different parameters such as viscosity and droplet size come into prominence for their characterization is a key factor in W/O/W emulsions. In this study, different emulsifiers (Crill™ 1, Crill™ 4, AMP, and PGPR) were studied to produce a casein-hydrolysate-loaded stable primary emulsion with lower viscosity and droplet size. Viscosity, electrical conductivity, particle size distribution, and emulsion stability were determined for three different dispersed phase ratios and three emulsifier concentrations. In 31 of the 36 examined emulsion systems, no electrical conductivity could be measured, indicating that appropriate emulsions were formed. While AMP-based emulsions showed non-Newtonian flow behaviors with high consistency coefficients, all PGPR-based emulsions and most of the Crill™-1- and -4-based ones were Newtonian fluids with relatively low viscosities (65.7–274.7 cP). The PGPR-based emulsions were stable for at least 5 days and had D(90) values lower than 2 µm, whereas Crill™-1- and -4-based emulsions had phase separation after 24 h and had minimum D(90) values of 6.8 µm. PGPR-based emulsions were found suitable and within PGPR-based emulsions, and the best formulation was determined by TOPSIS. Using 5% PGPR with a 25% dispersed phase ratio resulted in the highest relative closeness value. The results of this study showed that PGPR is a very effective emulsifier for stable casein-hydrolysate-loaded emulsion formations with low droplet size and viscosity.","PeriodicalId":10433,"journal":{"name":"Colloids and Interfaces","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2022-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43225177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mauricio Opazo-Navarrete, C. Burgos-Díaz, Karla A. Garrido-Miranda, Sergio-Miguel Acuña-Nelson
{"title":"Effect of Enzymatic Hydrolysis on Solubility and Emulsifying Properties of Lupin Proteins (Lupinus luteus)","authors":"Mauricio Opazo-Navarrete, C. Burgos-Díaz, Karla A. Garrido-Miranda, Sergio-Miguel Acuña-Nelson","doi":"10.3390/colloids6040082","DOIUrl":"https://doi.org/10.3390/colloids6040082","url":null,"abstract":"Solubility and emulsifying properties are important functional properties associated with proteins. However, many plant proteins have lower techno-functional properties, which limit their functional performance in many formulations. Therefore, the objective of this study was to investigate the effect of protein hydrolysis by commercial enzymes to improve their solubility and emulsifying properties. Lupin protein isolate (LPI) was hydrolyzed by 7 commercial proteases using different E/S ratios and hydrolysis times while the solubility and emulsifying properties were evaluated. The results showed that neutral and alkaline proteases are most efficient in hydrolyzing lupin proteins than acidic proteases. Among the proteases, Protamex® (alkaline protease) showed the highest DH values after 5 h of protein hydrolysis. Meanwhile, protein solubility of LPI hydrolysates was significantly higher (p < 0.05) than untreated LPI at all pH analyzed values. Moreover, the emulsifying capacity (EC) of undigested LPI was lower than most of the hydrolysates, except for acidic proteases, while emulsifying stability (ES) was significantly higher (p < 0.05) than most LPI hydrolysates by acidic proteases, except for LPI hydrolyzed with Acid Stable Protease with an E/S ratio of 0.04. In conclusion, the solubility, and emulsifying properties of lupin (Lupinus luteus) proteins can be improved by enzymatic hydrolysis using commercial enzymes.","PeriodicalId":10433,"journal":{"name":"Colloids and Interfaces","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42475514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Santini, Irene Nepita, A. Bykov, F. Ravera, L. Liggieri, S. Dowlati, A. Javadi, Reinhard Miller, G. Loglio
{"title":"Interfacial Dynamics of Adsorption Layers as Supports for Biomedical Research and Diagnostics","authors":"E. Santini, Irene Nepita, A. Bykov, F. Ravera, L. Liggieri, S. Dowlati, A. Javadi, Reinhard Miller, G. Loglio","doi":"10.3390/colloids6040081","DOIUrl":"https://doi.org/10.3390/colloids6040081","url":null,"abstract":"The input of chemical and physical sciences to life sciences is increasingly important. Surface science as a complex multidisciplinary research area provides many relevant practical tools to support research in medicine. The tensiometry and surface rheology of human biological liquids as diagnostic tools have been very successfully applied. Additionally, for the characterization of pulmonary surfactants, this methodology is essential to deepen the insights into the functionality of the lungs and for the most efficient administration of certain drugs. Problems in ophthalmology can be addressed using surface science methods, such as the stability of the wetting films and the development of artificial tears. The serious problem of obesity is fast-developing in many industrial countries and must be better understood, while therapies for its treatment must also be developed. Finally, the application of fullerenes as a suitable system for detecting cancer in humans is discussed.","PeriodicalId":10433,"journal":{"name":"Colloids and Interfaces","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41764440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Review on the Antioxidant Activity of Phenolics in o/w Emulsions along with the Impact of a Few Important Factors on Their Interfacial Behaviour","authors":"Sotirios N. Kiokias, V. Oreopoulou","doi":"10.3390/colloids6040079","DOIUrl":"https://doi.org/10.3390/colloids6040079","url":null,"abstract":"This review paper focuses on the antioxidant properties of phenolic compounds in oil in water (o/w) emulsion systems. The authors first provide an overview of the most recent studies on the activity of common, naturally occurring phenolic compounds against the oxidative deterioration of o/w emulsions. A screening of the latest literature was subsequently performed with the aim to elucidate how specific parameters (polarity, pH, emulsifiers, and synergistic action) affect the phenolic interfacial distribution, which in turn determines their antioxidant potential in food emulsion systems. An understanding of the interfacial activity of phenolic antioxidants could be of interest to food scientists working on the development of novel food products enriched with functional ingredients. It would also provide further insight to health scientists exploring the potentially beneficial properties of phenolic antioxidants against the oxidative damage of amphiphilic biological membranes (which link to serious pathologic conditions).","PeriodicalId":10433,"journal":{"name":"Colloids and Interfaces","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2022-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43257804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Khairul Azhar Mustapha, F. Shikh Anuar, Fatimah Al-Zahrah Mohd Saat
{"title":"Prediction of Slip Velocity at the Interface of Open-Cell Metal Foam Using 3D Printed Foams","authors":"Khairul Azhar Mustapha, F. Shikh Anuar, Fatimah Al-Zahrah Mohd Saat","doi":"10.3390/colloids6040080","DOIUrl":"https://doi.org/10.3390/colloids6040080","url":null,"abstract":"An open-cell metal foam gains a lot of interest from researchers due to its unique porous structure, which provides high surface area and good tortuosity, as well as being lightweight. However, the same structure also induces a massive pressure drop which requires an optimum design to suit applications, for example, a partially filled setup or staggered design. Thus, better attention to the slip velocity at the interface between the porous structure and non-porous region is required to maximize its potential, especially in thermal fluid applications. This study proposed a slip velocity model of an open-cell metal foam by using a reverse engineering method and 3D printing technology. A series of experiments and a dimensionless analysis using the Buckingham-Pi theorem were used to compute the slip velocity model. Results show that the pressure drop increases with decreasing pore size. However, the blockage ratio effects would be more significant on the pressure drop with foams of smaller pore sizes. The proposed slip velocity model for an open-cell metal foam agrees with the experimental data, where the predicted values fall within measurement uncertainty.","PeriodicalId":10433,"journal":{"name":"Colloids and Interfaces","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2022-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47388784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Polysaccharides-Based Injectable Hydrogels: Preparation, Characteristics, and Biomedical Applications","authors":"N. El-Sayed, S. Kamel","doi":"10.3390/colloids6040078","DOIUrl":"https://doi.org/10.3390/colloids6040078","url":null,"abstract":"Polysaccharides-based injectable hydrogels are a unique group of biodegradable and biocompatible materials that have shown great potential in the different biomedical fields. The biomolecules or cells can be simply blended with the hydrogel precursors with a high loading capacity by homogenous mixing. The different physical and chemical crosslinking approaches for preparing polysaccharide-based injectable hydrogels are reviewed. Additionally, the review highlights the recent work using polysaccharides-based injectable hydrogels as stimuli-responsive delivery vehicles for the controlled release of different therapeutic agents and viscoelastic matrix for cell encapsulation. Moreover, the application of polysaccharides-based injectable hydrogel in regenerative medicine as tissue scaffold and wound healing dressing is covered.","PeriodicalId":10433,"journal":{"name":"Colloids and Interfaces","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2022-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43211467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Krystalia Sarigiannidou, Davide Odelli, F. Jessen, M. Mohammadifar, Fatemeh Ajalloueian, Mar Vall-llosera, A. D. de Carvalho, Federico Casanova
{"title":"Interfacial Properties of Pea Protein Hydrolysate: The Effect of Ionic Strength","authors":"Krystalia Sarigiannidou, Davide Odelli, F. Jessen, M. Mohammadifar, Fatemeh Ajalloueian, Mar Vall-llosera, A. D. de Carvalho, Federico Casanova","doi":"10.3390/colloids6040076","DOIUrl":"https://doi.org/10.3390/colloids6040076","url":null,"abstract":"The effect of a tryptic hydrolysis as well as the effect of ionic strength (0–0.4 M NaCl) was investigated on the oil/water interfacial properties of soluble pea protein hydrolysate (SPPH) at neutral pH and room temperature (20 ± 0.01 °C). SEC-MALS and SDS-Page analysis showed that tryptic hydrolysis created a lower molecular weight polypeptide mixture, whereas FTIR analysis and DSC thermograms demonstrated a more disordered and flexible structure. The bulk properties of SPPH were studied in terms of hydrodynamic diameter and turbidity, where higher particle size (+ ~13 nm) and turbidity were observed at 0.4 M NaCl. Regarding the interfacial properties, the surface activity of SPPH improved by increasing ionic strength, with maximum interfacial pressure (14.28 mN/m) at 0.4 M NaCl. Nevertheless, the addition of NaCl negatively affected the elasticity and strength of the interfacial film, where the sample without salt exhibited the highest dilatational and shear storage modulus in all the frequencies considered.","PeriodicalId":10433,"journal":{"name":"Colloids and Interfaces","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2022-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46774186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
O. Koifman, A. Koptyaev, V. Travkin, P. Yunin, N. Somov, D. Masterov, G. Pakhomov
{"title":"Aggregation and Conductivity in Hot-Grown Petroporphyrin Films","authors":"O. Koifman, A. Koptyaev, V. Travkin, P. Yunin, N. Somov, D. Masterov, G. Pakhomov","doi":"10.3390/colloids6040077","DOIUrl":"https://doi.org/10.3390/colloids6040077","url":null,"abstract":"As a follow-up to our study on aggregation of metal-etioporphyrin complexes (Colloids Surf. A. Physicochem. Eng. Asp. 2022, 648, 129284), we considered thin films of three isomers of copper(II) etioporphyrin deposited on hot substrates. Despite the almost identical absorption spectra of isomers, their solid-state superstructures differ remarkably both in form and size. The lateral conductivity of films is much less sensitive to an isomer-type, regardless of the substrate temperature. However, the dark conductivity of cold-grown films is about two orders of magnitude higher than that of hot-grown films, whereas the photoconductivity of the latter is 100–1700 times greater, depending on the isomer.","PeriodicalId":10433,"journal":{"name":"Colloids and Interfaces","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2022-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44103996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alberto Martis, M. Fontana, M. Serrapede, S. Bianco, A. Chiodoni, C. Pirri, S. Bocchini
{"title":"Production of Graphene Stably Dispersible in Ethanol by Microwave Reaction","authors":"Alberto Martis, M. Fontana, M. Serrapede, S. Bianco, A. Chiodoni, C. Pirri, S. Bocchini","doi":"10.3390/colloids6040075","DOIUrl":"https://doi.org/10.3390/colloids6040075","url":null,"abstract":"Graphene is a 2D carbon material with peculiar features such as high electrical conductivity, high thermal conductivity, mechanical stability, and a high ratio between surface and thickness. Applications are continuously growing, and the possibility of dispersing graphene in low-boiling green solvents could reduce its global environmental impact. Pristine graphene can be dispersed in high concentration only in polar aprotic solvents that usually have high boiling points and high toxicity. For this reason, the oxidized form of graphene is always used, as it is easier to disperse and to subsequently reduce to reduced graphene oxide. However, compared to pristine graphene, reduced graphene oxide has more defects and has inferior properties respect to graphene. In this work, the polymerization of (diethyl maleate derivate) on graphene obtained by sonication was performed in a microwave reactor. The obtained material has good stability in ethanol even after a long period of time, therefore, it can be used to deposit graphene by mass production of inks or by casting and easy removal of the solvent. The thermal annealing by heating at 300–400 °C in inert atmosphere allows the removal of the polymer to obtain pristine graphene with a low number of defects.","PeriodicalId":10433,"journal":{"name":"Colloids and Interfaces","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2022-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43834241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}