Journal of Colloid and Interface Science
○ Elsevier BV
Preprints posted in the last 30 days, ranked by how well they match Journal of Colloid and Interface Science's content profile, based on 12 papers previously published here. The average preprint has a 0.02% match score for this journal, so anything above that is already an above-average fit.
Yang, E.; Khongkomolsakul, W.; Dadmohammadi, Y.; Abbaspourrad, A.
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In vegetarian diets, phytate is known to disrupt the adsorption of minerals. Fortifying foods with phytase, a therapeutic enzyme known to mitigate phytate, might increase the uptake of important nutrients. Phytase is susceptible to environmental stress such as heat and acidic conditions encountered during food processing. Therefore, we developed and optimized a core-shell microparticle composed of a phytase-chitosan core and a shell consisting of cross-linked alginate-{kappa}-carrageenan. Ethanol was used to precipitate the microparticles, and the ethanol concentration was optimized along with the chitosan and phytase ratio and the alginate-carrageenan concentration, to form stable core-shell microparticles. The optimized core-shell microparticles have a loading capacity of 32.7% with a high encapsulation efficiency of 80.3% and uniform micro-size with a diameter of 3.2 {micro}m and a poly-dispersity index of 0.178. Loaded phytase retained 62.7% enzymatic activity after heat treatment and digestion conditions. These results indicate that core-shell microparticles are suitable for retaining enzyme activity within the food matrix under typical food processing conditions. HighlightsO_LIDevelopment of size-controlled core-shell microparticles to protect phytase C_LIO_LIPhytase-chitosan microparticles are surrounded by an alginate-{kappa}-carrageenan shell C_LIO_LIOptimization achieved 32.7% loading capacity with a uniform size of 3.2 {micro}m C_LIO_LICore-shell microparticles retained 62.7% enzyme activity after heat and digestion C_LIO_LIPhytase powder (2 mg) is required for a single maize meal C_LI
Kim, J.; Bartholomew, S. N.; Zeno, W. F.
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Manufacturing and storage processes can expose microbes to oxidative stress, reducing viability and limiting their use in biotechnological applications. Here, we evaluate graphene quantum dots (GQDs) containing hydroxyl and carboxyl groups as protective additives that mitigate peroxide-induced oxidative stress in Escherichia coli. GQDs did not adversely affect bacterial growth under basal conditions and restored growth in the presence of hydrogen peroxide. Using the membrane-partitioning fluorescent probe C11-BODIPY, we found that GQDs reduced peroxide-induced oxidation in bacterial membranes. We further used redox-sensitive roGFP2 probes to monitor intracellular oxidative stress and found that GQDs suppressed intracellular hydrogen peroxide accumulation and attenuated disruption of glutathione redox homeostasis. Together, these results show that GQDs protect bacteria by limiting peroxide-driven oxidative damage at both membrane and intracellular levels. This work supports the potential use of GQDs as protective additives for microbial formulations that are susceptible to oxidative stress.
Kear, E.; Bernach, M.; Nock, V.; Remus-Emsermann, M.
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Polydimethylsiloxane (PDMS) is an excellent material for the construction of biomimetic leaf replicas which reproduce leaf surfaces with high fidelity. This allows for the study of leaf surface-colonizing bacteria and the impact of the leaf topology on bacterial distributions and behavior. However, their application is limited to short-term experiments, as long term survival of microorganisms on their surface is not possible due to a lack of nutrient replenishment. On living leaves, nutrients diffuse across the cuticle via leaching, a process not yet replicated in biomimetic systems. Here, we explore whether water and fructose can be supplied to microbial colonizers on PDMS membranes by mimicking leaching. We created hybrid membranes by incorporating polymers (Carbopol, Pemulen, cellulose microfibers, cellulose nanocrystals, and polyvinylpyrrolidone) to enhance nutrient transport. We determined that bulk diffusion of water correlated negatively with membrane thickness and positively with polymer concentration. Further, fructose diffusion across hybrid membranes reached similar rates compared to isolated Populus x canescens leaf cuticles. Under high relative humidity, these membranes supported long-term bacterial survival. Our findings represent important steps towards the development of topomimetic leaf surfaces that sustain microbial life, enabling further investigation into the microbe-microbe interactions that take place on leaves.
Morgenstein, L.; Huang-Zhu, C. A.; Yudovich, S.; Grupi, A.; Van Lehn, R. C.; Weiss, S.
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Surface functionalization of inorganic quantum dot nanoparticles is of great interest in the application of these materials toward a wide range of biological applications where membrane interactions are critical. The use of amphiphilic lipids to functionalize the surfaces of quantum dots represents a promising alternative to produce water-soluble and membrane-active materials with facile tuning of the quantum dots surface properties. Here, we demonstrate an experimental approach that yields lipid-coated quantum dots with highly tunable surface charge by controlling the concentration of cationic lipids during preparation. Through fluorescence-activated cell sorting assays, we show that these cationic lipid-coated quantum dots can enhance membrane interactions and increase membrane labeling density in live HEK293 cells. We further employed coarse-grained molecular dynamics simulations to model the lipid self-assembly process using an implicit solvent force field and subsequently model the adsorption of lipid-coated quantum dots to model membranes. Our simulations show that we can control the effective surface charge of lipid-coated quantum dots and influence the strength of adsorption to oppositely charged lipid membranes, a process that is mediated by the release of counterions at the quantum dot-membrane interface. This work supports the future development of biocompatible and water-soluble inorganic nanoparticles with highly tunable surfaces, and provides mechanistic insight into how different lipids can influence nanoparticle-membrane interactions at a molecular scale.
Campbell, O.; Leal, C.; Monje, V.
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In mammalian cells, lipid monolayers support the integrity of lipid droplets (LDs), organelles that function as storage for neutral lipids. Liver-targeting illnesses such as liver cancer interrupt normal LD metabolism and prompt changes in the chemical content of these organelles, which can have effects on structural and organizational behavior of the lipids. In LDs, liver cancer induces concentric crystalline phases of cholesteryl esters (CEs) and triglycerides near the NL-monolayer interface, which become more pronounced as CE concentration increases. Yet, there is little known about how this phenomenon may link to persistence of undigested LDs in liver cancer patients. To shed light on this, all-atom molecular dynamics simulations were used to model LD micropipette aspiration experiments and gain insight into the effect of CE concentration on partitioning, structural, and mechanical properties of LDs. We successfully model micropipette aspiration by application of constant surface tension laterally, which stretches lipid bilayers and monolayers as the magnitude increased. The results show increased phospholipid packing due to insertion of CE fatty tails into the monolayer. Increasing CE concentration induces a non-linear change in surface packing defects on the LDs, notable rigidification, and stiffness. Taken together, these insights improve our understanding of the physical properties at the LD monolayer-core interface during liver cancer progression.
Berkes, E. A.; Oron, O.; Wood, A. K.; Monsul, P. N.; Monsul, N. T.
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Micro- and nanoplastics (MNPs) are now recognized as ubiquitous dietary and environmental contaminants, yet practical strategies to reduce gastrointestinal exposure remain limited. This study evaluated whether Qi601, a heat-inactivated Limosilactobacillus fermentum biofilm-derived postbiotic, could bind plastic particles and reduce intestinal epithelial plastic burden. Prior probiotic studies have demonstrated live bacterial adsorption of MNPs and mitigation of MNP-associated toxicity in vivo; here, we evaluate whether a nonviable postbiotic preparation can produce analogous MNP-binding and epithelial-protective effects. Qi601 durably bound polystyrene nanoplastics under in vitro simulated digestion conditions. In Caco-2 intestinal epithelial monolayers, Qi601 reduced surface-associated and intracellular nanoplastic burden in both protection and rescue models, indicating decreased epithelial particle interaction both before and after established nanoplastic exposure. Multimodal imaging, including confocal microscopy, atomic force microscopy, and scanning electron microscopy, confirmed close physical association between Qi601 and nanoplastics. Finally, a first-in-human proof-of-concept chewing-gum study showed Qi601 binding in the human mouth to heterogeneous gum-derived microplastic fragments released during mastication. Together, these findings support the concept of postbiotic intervention for gastrointestinal epithelial protection against ingested MNPs.
Graves, S.; Jasinski, M.; Olsen, E.; Kamanzi, A.; Zhang, Y.; Leung, J.; Venier-Karzis, M.; Safaeesirat, A.; Cullis, P.; Leslie, S. R.
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The optimization of mRNA-lipid nanoparticles (mRNA-LNPs) for therapeutic applications is limited in part by the inadequate characterization of mRNA payload heterogeneity. One current challenge is accurately measuring the number of mRNA copies within individual LNPs, where the standard method of intensity-based mRNA number determination is sensitive to fluorescent dye-dye interactions and heterogeneity of mRNA labeling. Here we present a single-particle microscopy method that combines direct counting of the mRNA copies per LNP with LNP size measurements. While confined in microwells, individual mRNA-LNPs are lysed to release their cargo and stained with a dye such that the number of mRNA molecules in each well can be directly counted using fluorescence microscopy. Since the method stains the mRNA cargo in situ, it enables characterization of LNPs formulated with therapeutic grade (e.g., unlabeled) mRNA. We applied this approach to two Onpattro(R)-based LNP formulations prepared using different formulation buffers, where the two formulations had different average mRNA copy number, particle size, and fraction of LNPs lacking mRNA. The ability to directly count the number of mRNA molecules in LNPs establishes a complimentary method to intensity-based mRNA number determination and supports the characterization and screening of clinically relevant LNP formulations.
Odudimu, A. T.; Wittenberg, N. J.
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Significant cellular processes, including protein sorting, signal transduction, and pathogen entry, amongst others, are associated with membrane microdomains, also known as lipid rafts. Lipid rafts, due to their unique biophysical properties compared to their surrounding environment, which stem from their distinct lipid and protein profiles, have garnered interest in methods and techniques that tune their coexisting liquid-ordered/liquid-disordered state, aiming to disrupt or destabilize them. Since cholesterol stabilizes the membrane domain, cholesterol-depleting compounds like cyclodextrin can be used to destabilize and disrupt the membrane rafts. Overall, given the membrane rafts importance in biological processes, it is crucial to understand the biophysical factors that influence its stability. In this study, we present a new method for disrupting and dissolving lipid rafts in a model system of phase-separated supported lipid bilayer (SLB) patches composed of DOPC, DPPC, and cholesterol. Using fluorescence microscopy to monitor the liquid ordered (Lo) and liquid disordered (Ld) phases of the SLB patches, we observed that adding DOPC liposomes causes a transformation of the co-existing Ld and Lo phases into a single-phase bilayer. On the other hand, adding liposomes that match the lipid content of the phase-separated SLB patch increase the areas of the existing Ld and Lo phases. This work also offers a new method for redistributing raft-localized molecules, confirmed by tracking the redistribution of cholera toxin bound to GM1 after domain dissolution with DOPC liposomes. The work describes an alternative method for dynamically altering membrane composition and dissolving domains via liposome addition, rather than lipid depletion or exchange.
Polley, A.; Ravikumar, A.; Shanmugam, S.
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Liposomes are self-assembled lipid vesicles capable of encapsulating both hydrophilic and hydrophobic therapeutics, making them versatile platforms in drug delivery and biomedical technology. In this study, the limitations of the classical thin-film hydration method were critically evaluated, and a sustainable, systematically optimized strategy was established for generating defined liposomal lamellar phases. Hydration conditions were optimized, and 4 mL of buffer per 10 mg of lipid was determined to be optimal for effective rehydration and improved statistical reliability of vesicle measurements. A refined probe-sonication protocol (20% amplitude, 5 s ON/55 s OFF pulse) enabled controlled transformation of multivesicular vesicles into stable multilamellar and unilamellar vesicles at net ON-times of 90 s and 185 s, respectively, without overheating or contamination. In addition, a Python-based machine-learning tool was developed for vesicle size characterization. Collectively, these optimizations provided a reproducible and sustainable framework for preparing liposomes across different lamellar phases.
Garg, A.; Barik, S.; Nair, H.; Nair, S. G.; Kiran Kumar, J. K.; Kanchi, S.
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Curcumin-functionalized gold nanoclusters are promising platforms for catalysis and drug delivery, yet the molecular determinants of their stability, morphology, and solvent response remain unclear. Here, microsecond all-atom molecular dynamics simulations are employed to investigate a 2 nm gold nanoparticle noncovalently coated with different curcumin forms, including neutral enol and trans-keto tautomers, the deprotonated enolate, and their mixtures in water-ethanol and water-methanol solvents. Layer-resolved analyses of radius of gyration, density profiles, and surface coverage reveal that neutral enol and trans forms generate compact assemblies with near-complete surface coverage, whereas enolate-rich systems adopt more expanded conformations with solvent-exposed molecules. Mixed systems preserve these intrinsic packing characteristics while improving overall coverage. Solvent substitution from ethanol to methanol reduces {pi}-{pi} stacking, strengthens Au-curcumin interactions, and increases surface coverage, yielding more compact nanostructures. Free energy and potential of mean force calculations indicate that deprotonated curcumin most effectively screens Au-Au interactions and stabilizes dispersed nanoparticles, while neutral tautomers provide moderate stabilization. Curcumin also enhances the loading of anticancer drug doxorubicin (DOX) onto Au nanoparticles, improving biocompatibility. Enolate(An)-containing systems produce extended structures with weaker membrane interactions, whereas neutral curcumin complexes form compact, positively charged assemblies that strongly bind to negatively charged cancer cell membranes. These findings clarify how tautomeric state and solvent environment cooperatively govern interfacial organization and colloidal stability, establish design guidelines for curcumin-based gold nanocarriers in catalysis, sensing, and drug delivery applications.
Kuyler, G. C.; Murray, R. J.; Khwaja, F. N.; Gunner, J.; Klumperman, B.; Poyner, D.; Ayub, H.; Wheatley, M.
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Detergent-free extraction of membrane proteins using polymers directly into nanodiscs from the cell membrane has been used widely in recent years. Since the first use of poly(styrene-co-maleic acid) (SMA), numerous related polymers have been developed that differ in chemical architecture and nanodisc characteristics, each capable of influencing the structural and functional properties of the encapsulated membrane protein and its surrounding lipids. Identifying an optimal solubilising polymer, therefore, requires consideration not only of extraction efficiency but also compatibility with downstream applications and analyses. Polymer series in which a single parameter is systematically varied provide a valuable, nuanced tool for optimising nanodisc utility in downstream applications. This study utilises a chemically defined series of poly(styrene-co-maleic acid-co-(N-benzyl)maleimide) (BzAM) terpolymers that exhibit a stepwise, systematic increase in hydrophobicity. Using the human calcitonin gene-related peptide (CGRP) receptor as an exemplar class B1 G-protein-coupled receptor (GPCR), the ability of each BzAM terpolymer to solubilise the receptor from mammalian cell membranes was assessed. All members of the series successfully solubilised CGRP receptor, with solubilisation efficiency correlating positively with increasing hydrophobicity. Importantly, the receptor retained its characteristic high-affinity ligand-binding capability when encapsulated within the BzAM nanodisc, demonstrating that functional integrity is preserved following BzAM-mediated extraction and purification. These findings establish the BzAM terpolymer series as a systematic, tuneable, well-defined tool for the detergent-free solubilisation and functional investigation of GPCRs, and other membrane proteins, in near-native lipid environments. HIGHLIGHTSO_LIStepwise-tuned poly(styrene-co-maleic acid-co-(N-benzyl)maleimide) (BzAM) terpolymers provide a chemically defined, hydrophobicity-controlled platform for detergent-free membrane protein extraction. C_LIO_LIAll BzAM variants effectively solubilise the human calcitonin gene-related peptide (CGRP) receptor, with extraction efficiency increasing in line with terpolymer hydrophobicity. C_LIO_LICGRP receptor maintains high-affinity ligand binding in BzAM nanodiscs, demonstrating preservation of ligand-binding function after solubilisation. C_LIO_LIThe BzAM series provides a novel platform for studying G-protein-coupled receptors and other membrane proteins in near-native lipid environments, with the potential to deliver mechanistic insights and support future drug-discovery efforts. C_LI GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/726474v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@1cb167corg.highwire.dtl.DTLVardef@313e60org.highwire.dtl.DTLVardef@f64a2borg.highwire.dtl.DTLVardef@17f6629_HPS_FORMAT_FIGEXP M_FIG C_FIG
Shakeri, F.; Mehdian, H.; Bakhtiyari-Ramezani, M.; Amini, E.; Hajisharifi, K.
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Staphylococcus aureus (S. aureus) is the most common pathogen associated with skin infections worldwide. Significant efforts have been made to identify and develop innovative therapeutic strategies against S. aureus as alternatives to conventional antibiotics. Physical plasma has a broad range of potential uses, with non-destructive disinfection being one of its earliest applications. Although the literature emphasizes the antibacterial properties of cold atmospheric plasma (CAP), the effect of plasma on S. aureus on damaged skin susceptible to S. aureus invasion through the itch-scratch cycle has not been studied to date. Thus, we examined the effectiveness of CAP treatment on S. aureus bacteria in atopic dermatitis lesions using floating electrode dielectric barrier discharge devices, as well as helium and argon plasma jets. Heat distribution on the skin target, ultraviolet C radiation, and ozone generation of plasma jets for the operator of plasma sources were evaluated. Microbial tests confirmed the presence of S. aureus on the lesions of the groups before treatment. The groups exposed to plasma treatment showed a notable reduction in bacterial population compared to the model group (p<0.05). Furthermore, our investigation indicated that plasma treatment reduced pruritus behavior. The findings suggest that cold atmospheric plasma treatment may potentially target skin infections caused by S. aureus in addition to conventional therapies.
Odahara, M.; Horii, Y.; Xu, T.; Terada, K.; Daicho, K.; Shiomi, J.; Numata, K.
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Bio-based materials are known for their excellent biodegradability and, in some cases, their potential to fix carbon dioxide. Owing to these properties, they are increasingly being utilized as environmentally friendly alternatives across various applications. In this study, we focused on using living cells themselves as material components, aiming to evaluate their potential as substitutes for conventional plastic-based thermal insulators. We selected two types of cells, photosynthetic purple non-sulfur bacterium Rhodovulum sulfidophilum and tobacco BY-2 plant suspension cells. After optimizing solidification conditions through the addition of pectin and cellulose nanofibers, we measured the thermal conductivity of the solidified cells under atmospheric pressure. The results showed that R. sulfidophilum exhibited 0.0553 W/m{middle dot}K, while BY-2 exhibited a thermal conductivity of 0.043 W/m{middle dot}K. Both values indicate relatively low thermal conductivity compared to existing bio-based materials, suggesting high insulation performance. Among the solidified cells, the solidified BY-2 cells showed minimal variation in thermal insulation performance under pressure changes, and had a low thermal emissivity as revealed by FT-IR analysis. Based on these findings, we propose that cell-derived materials can serve as potentially biodegradable bio-based thermal insulation materials.
Aye, S. L.; Fadaei, F.; Gomibuchi, Y.; Suzuki, Y.; Prakash, P. S.; Chandrasekhar, S.; Yasunaga, T.; Schmidt, T.-L.; Sato, Y.
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Membrane models of scaffolded discoidal lipid bilayers called nanodiscs have proven to be a valuable tool for the study of membrane proteins in a native environment. DNA-scaffolded membrane model has emerged as an alternative tool for membrane protein studies. Taking advantage of the designability of DNA nanostructure, we created a double-decker double-stranded DNA ring (DDring) to self-assemble DNA-based nanodiscs (DNA-ND). The DDring is 17 nm wide and 4 nm high, and equipped with 28 alkyl chains on the inside that can interact with each hydrophobic leaflet of the lipid bilayer. We further demonstrate the functionality of DNA-ND membrane model with the assembly of membrane proteins. DDrings are suited to neutral or cationic charged phospholipids and detergents. This study provides more insights into the potential use of DNA- assisted nanodiscs for membrane protein characterization.
Sanchez-Velazquez, G.; Porter, T. K.; Ospina, L.; Alizadehmojarad, A. A.; Yim, W.; Wang, X.; Strano, M.
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Proteins in solution adsorb to the corona of nanoparticles such as single-walled carbon nanotubes (SWCNTs), but these interactions are difficult to predict and analyze due to ambiguities in the structure of the latter. In this work, we employ ss(GT)15-DNA wrapped SWCNTs, a commonly used fluorescent sensor construct, to examine protein adsorption by quantifying binding dissociation constants and characterizing the corresponding photophysical effects. A library of 20 proteins are used to evaluate adsorption-induced changes in photoluminescence (PL) intensity ({Delta}I/I0) and emission wavelength upon solution phase binding. We find that 15 proteins produce monotonic dose-response behavior well described using a single-site Langmuir model. Alternatively, five proteins exhibited more complex, non-monotonic behavior consistent with a two-step binding model representing protein-protein interactions coupled to adsorption. The study reveals that metalloproteins, which comprised 12 of the 20 proteins in the library, induced greater PL quenching compared with metal-free proteins for this system, with maximum binding-associated quenching ({Delta}I/I0) of 94% for metalloproteins versus 20% for metal-free proteins. For metalloproteins, we introduce a proximity-based quenching framework in which protein size provides a coarse proxy for cofactor-SWCNT separation, offering a mechanistic interpretation of the observed quenching variation across proteins. Together, these results establish the use of metal coordination sites, such as those in metalloproteins, to assist the transduction of certain nanoparticle fluorescent sensors, helping with sensor probe design and interpretation in biological environments.
Viroja, J.; Rajput, K.; Jain, S.; Bhatia, D. D.
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Tetrahedral DNA nanostructures (TDNs) are promising nanocarriers due to their structural precision, biocompatibility, and efficient cellular uptake. However, their stability under physiological conditions remains a key challenge. In this study, TDNs were synthesized via a one-pot thermal annealing method and characterized using native PAGE, dynamic light scattering (DLS), and zeta potential analysis, confirming uniform size ([~]13 nm) and negative surface charge. Their stability was systematically evaluated across different biological media (DMEM complete, serum-free DMEM, and E3), temperatures (4 {degrees}C, 25 {degrees}C, and 37 {degrees}C), and pH conditions (4.0, 7.0, and 8.5) over 24 h. Results revealed rapid degradation in serum-containing medium, increased instability at higher temperatures, and reduced stability under acidic conditions, while serum-free, lower-temperature, and neutral to mildly basic environments enhanced structural integrity. These findings highlight the strong environmental dependence of TDN stability and provide insights for optimizing their design for biomedical applications.
Lee, J.; Kim, B. H.
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This study investigates the potential of the garden rhizosphere as a source of electrochemically active bacteria (EAB) for operating microbial fuel cells (MFCs). We evaluated a diverse array of garden flora, including vegetables (lettuce, Chinese cabbage), flowering plants (August lily, peppermint), and woody species (pine, oak, ginkgo, and bush clover). Among the tested groups, MFCs inoculated with peppermint and ginkgo rhizosphere microbiotas exhibited the highest current densities within their respective categories, significantly outperforming control groups without plant components. 16S rRNA gene microbial community analysis revealed that the initial rhizosphere environment acts as a decisive selective pressure, shaping distinct anode biofilms based on plant types (herbaceous vs. woody). Despite these structural differences in microbial assembly, high current generation was achieved in both peppermint and ginkgo systems, suggesting a high degree of functional redundancy within the rhizosphere-derived consortia. These findings demonstrate that various garden ecosystems can serve as robust biological reservoirs for MFC operation, where diverse microbial configurations are capable of sustaining efficient bio-electrochemical energy conversion.
Merlo, A.; Medin, J.; Dahlin, A.; Grandfield, K.; Sask, K. N.
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Surface functionalization of biomaterials enables the immobilization of proteins and other molecules and can be utilized to direct the biological response to devices and implants. Fetuin-A is a blood plasma protein involved in numerous physiological processes, including the regulation of mineralization. Notably, many investigations of fetuin-A have explored its cellular interaction when in solution, but limited studies report the role of fetuin-A when used as a surface modifier. The present investigation explores the response elicited by fetuin-A on Saos-2 cells when it is immobilized on a model gold surface through the covalent reaction with dithiobis(succinimdyl propionate) (DSP). Comparative surface characterization using x-ray photoelectron spectroscopy (XPS), atomic force microscopy - infrared spectroscopy (AFM-IR) and surface plasmon resonance (SPR) confirmed the surface modifications but indicate partial inhomogeneity in the functionalizer surface coverage. The interaction of albumin and fetuin-A with the surface was quantified by radiolabeling, quartz crystal microbalance with dissipation (QCM-D) and SPR, demonstrating a higher mass of fetuin-A bound to the surface in comparison to serum albumin. Over 7 days, cells bound to the surfaces with immobilized fetuin-A showed significantly hindered proliferation of osteoblast-like cells compared to the positive control (fibronectin), presumably due to a decrease in cell metabolism. This study provides new insights into the role of fetuin-A in regulating Saos2 cell response and elucidates its potential use in combination with chemical functionalizers for biomedical applications requiring surface modification.
Saarela, S.; Härkönen, K.; Laari, M.-I.; Sivonen, M.; Strandin, T.; Hepojoki, J.; Niskanen, E.; Lehto, V.-P.; Xu, W.
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Lipid nanoparticles (LNPs) have demonstrated strong potential in COVID-19 mRNA vaccines nevertheless they still face the challenges in low mRNA delivery efficacy. Virus-like porous silica (VLPSi) nanoparticles (NPs) represent a promising biomimetic delivery platform because their spiked morphology may enhance cellular internalization and promote endosomal membrane disruption. However, the application of VLPSi for mRNA has been rarely explored. In this study, hybrid lipid-VLPSi NPs were developed by combining VLPSi with either lipoplexes (LPs) or LNPs. The effects of lipid types, mass ratio of different compositions, and amine modifications of VLPSi on mRNA delivery were studied. The results demonstrated that both LP and LNP could be successfully integrated with VLPSi to form hybrid delivery systems for mRNA transfection. VLPSi could significantly enhance mRNA delivery of both LPs and LNPs due to improved cellular uptake, structural stabilization of the mRNA complex, and enhanced endosomal escape mediated by the rigid virus-like surface architecture. Among the tested lipid formulations, the ionizable lipid ALC-0315 and helper lipid DOPE with mass ratio of 5:3 was the most effective lipid composition to be integrated with VLPSi, showing the highest mRNA delivery performance. In addition, amino modification of VLPSi was found to be a critical factor for efficient mRNA delivery. Hybrid LNPs containing amino-modified VLPSi showed significantly higher transfection efficiency than those containing unmodified VLPSi. Notably, amino-modified LNP-VLPSi achieved up to fivefold higher gene expression than conventional LNPs. Overall, this study establishes VLPSi as an efficient platform for amplifying lipid-mediated mRNA delivery. Owing to its straightforward integration into widely used LNP systems, VLPSi offers an adaptable and effective strategy for advancing next-generation mRNA therapeutics.
Pavlov, E.; Mohamed, N.; Artemchuk, O.; Rabieh, S.; Peixoto, P.; Bromage, T.
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The patch-clamp experimental technique is widely used to study the electrical properties of ion channels in biological and artificial lipid membranes. The key to the high quality of the experiments is the manufacturing of glass pipettes that provide highly electrically resistant contact between the edge of the pipette tip and the lipid bilayer. Preparation of the pipettes is particularly challenging for studies of the mitochondrial membranes due to the need for very small pipette tip sizes. Here, we present a robust procedure for producing pipettes suitable for experiments with native mitochondrial membranes. This procedure involves a two-step approach: initial fabrication of relatively large glass micropipettes using a standard micropipette puller, followed by tip refinement using a microforger to achieve smooth glass surface and reduced opening size. Pipette tip diameters and surface structure were examined using field emission - scanning electron microscopy (FE-SEM) imaging to assess the effects of variable parameters on pipette geometry and size. The resulting pipettes were validated in patch-clamp recording of the mitochondrial inner membranes. This approach enables the reproducible production of optimized pipettes for mitochondrial patch-clamp experiments, improving the quality and throughput of electrophysiological recordings of the mitochondrial ion channels.