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Kocherbitov, V. (2023). A model for water sorption isotherms and hydration forces in sugar surfactants. Journal of Colloid and Interface Science, 633, 343-351
Öppna denna publikation i ny flik eller fönster >>A model for water sorption isotherms and hydration forces in sugar surfactants
2023 (Engelska)Ingår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 633, s. 343-351Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

HYPOTHESIS: Hydration forces between surfactant bilayers can be assessed using water sorption isotherms of surfactants. For a quantitative description, a water sorption model that relates water activity to water content in surfactant-based systems should be proposed.

THEORY AND SIMULATIONS: A water sorption model for nonionic surfactant systems based on the idea on partial solvent accessibility is proposed. The model contains only two parameters: one describes the strength of interactions, the other describes the fraction of surfactant available for water. For comparison, molecular dynamics simulations of bilayers of n-octyl β-d-glucoside with different water contents are presented.

FINDINGS: The model provides an excellent fit of experimental data on water sorption isotherms of two sugar surfactants. The results of the fitting are compared with molecular dynamics simulations and show a good correlation between simulations and the theory proposed. Analysis of interaction energies shows weakly endothermic hydration both in the simulations and in the sorption model, which agrees with calorimetric data on hydration. The model also shows a non-exponential decay of hydration forces with respect to the distance between bilayers; an expression for the decay length is derived.

Ort, förlag, år, upplaga, sidor
Elsevier, 2023
Nyckelord
Enthalpy, Entropy, Hydration forces, Liquid crystalline phase, Non-ionic surfactants, Solvent accessibility, Water activity, Water sorption isotherm
Nationell ämneskategori
Materialkemi
Identifikatorer
urn:nbn:se:mau:diva-56629 (URN)10.1016/j.jcis.2022.11.088 (DOI)000908352700013 ()36459939 (PubMedID)
Tillgänglig från: 2022-12-13 Skapad: 2022-12-13 Senast uppdaterad: 2023-03-06Bibliografiskt granskad
Bogdanova, E., Lages, S., Phan-Xuan, T., Kamal, M. A., Terry, A., Millqvist Fureby, A. & Kocherbitov, V. (2023). Lysozyme-Sucrose Interactions in the Solid State: Glass Transition, Denaturation, and the Effect of Residual Water.. Molecular Pharmaceutics, 20(9), 4664-4675
Öppna denna publikation i ny flik eller fönster >>Lysozyme-Sucrose Interactions in the Solid State: Glass Transition, Denaturation, and the Effect of Residual Water.
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2023 (Engelska)Ingår i: Molecular Pharmaceutics, ISSN 1543-8384, E-ISSN 1543-8392, Vol. 20, nr 9, s. 4664-4675Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The freeze-drying of proteins, along with excipients, offers a solution for increasing the shelf-life of protein pharmaceuticals. Using differential scanning calorimetry, thermogravimetric analysis, sorption calorimetry, and synchrotron small-angle X-ray scattering (SAXS), we have characterized the properties at low (re)hydration levels of the protein lysozyme, which was freeze-dried together with the excipient sucrose. We observe that the residual moisture content in these samples increases with the addition of lysozyme. This results from an increase in equilibrium water content with lysozyme concentration at constant water activity. Furthermore, we also observed an increase in the glass transition temperature (Tg) of the mixtures with increasing lysozyme concentration. Analysis of the heat capacity step of the mixtures indicates that lysozyme does not participate in the glass transition of the sucrose matrix; as a result, the observed increase in the Tg of the mixtures is the consequence of the confinement of the amorphous sucrose domains in the interstitial space between the lysozyme molecules. Sorption calorimetry experiments demonstrate that the hydration behavior of this formulation is similar to that of the pure amorphous sucrose, while the presence of lysozyme only shifts the sucrose transitions. SAXS analysis of amorphous lysozyme–sucrose mixtures and unfolding of lysozyme in this environment show that prior to unfolding, the size and shape of lysozyme in a solid sucrose matrix are consistent with its native state in an aqueous solution. The results obtained from our study will provide a better understanding of the low hydration behavior of protein–excipient mixtures and support the improved formulation of biologics.

Ort, förlag, år, upplaga, sidor
American Chemical Society (ACS), 2023
Nyckelord
differential scanning calorimetry, glass transition, hydration, proteins, small-angle X-ray scattering, solid-state formulations
Nationell ämneskategori
Fysikalisk kemi
Identifikatorer
urn:nbn:se:mau:diva-62084 (URN)10.1021/acs.molpharmaceut.3c00403 (DOI)001044988400001 ()37555640 (PubMedID)2-s2.0-85168498460 (Scopus ID)
Tillgänglig från: 2023-08-23 Skapad: 2023-08-23 Senast uppdaterad: 2023-09-19Bibliografiskt granskad
Slaninova, E., Obruca, S., Kocherbitov, V. & Sedlacek, P. (2023). On the bioprotective effects of 3-hydroxybutyrate: Thermodynamic study of binary 3HB-water systems.. Biophysical Journal, 122(3), 460-469, Article ID S0006-3495(23)00004-8.
Öppna denna publikation i ny flik eller fönster >>On the bioprotective effects of 3-hydroxybutyrate: Thermodynamic study of binary 3HB-water systems.
2023 (Engelska)Ingår i: Biophysical Journal, ISSN 0006-3495, E-ISSN 1542-0086, Vol. 122, nr 3, s. 460-469, artikel-id S0006-3495(23)00004-8Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Microorganisms must face various inconvenient conditions; therefore, they developed several approaches for protection. Such a strategy also involves the accumulation of compatible solutes, also called osmolytes. It has been proved that the monomer unit 3-hydroxybutyrate (3HB), which is present in sufficient concentration in poly(3-hydroxybutyrate) (PHB)-accumulating cells, serves as a chemical chaperone protecting enzymes against heat and oxidative stress and as a cryoprotectant for enzymes, bacterial cells, and yeast. The stress robustness of the cells is also strongly dependent on the behavior and state of intracellular water, especially during stress exposure. For a better understanding of the protective mechanism and effect of strongly hydrophilic 3HB in solutions at a wide range of temperatures, a binary phase diagram of system sodium 3HB (Na3HB)-water in equilibrium and the state diagrams showing the glass transitions in the system were constructed. To investigate the activity of water in various compositions of the Na3HB/water system, three experimental techniques have been used (dynamic water sorption analysis, water activity measurements, and sorption calorimetry). First, Na3HB proved its hydrophilic nature, which is very comparable with known compatible solutes (trehalose). Results of differential scanning calorimetry demonstrated that Na3HB is also highly effective in depressing the freezing point and generating a large amount of nonfrozen water (1.35 g of water per gram of Na3HB). Therefore, Na3HB represents a very effective cryoprotectant that can be widely used for numerous applications.

Ort, förlag, år, upplaga, sidor
Elsevier, 2023
Nationell ämneskategori
Polymerkemi
Identifikatorer
urn:nbn:se:mau:diva-58508 (URN)10.1016/j.bpj.2023.01.004 (DOI)000935472000001 ()36617191 (PubMedID)
Tillgänglig från: 2023-03-02 Skapad: 2023-03-02 Senast uppdaterad: 2023-03-20Bibliografiskt granskad
Engstedt, J., Barauskas, J. & Kocherbitov, V. (2023). Phase behavior of soybean phosphatidylcholine and glycerol dioleate in hydrated and dehydrated states studied by small-angle X-ray scattering. Soft Matter, 19(43), 8305-8317
Öppna denna publikation i ny flik eller fönster >>Phase behavior of soybean phosphatidylcholine and glycerol dioleate in hydrated and dehydrated states studied by small-angle X-ray scattering
2023 (Engelska)Ingår i: Soft Matter, ISSN 1744-683X, E-ISSN 1744-6848, Vol. 19, nr 43, s. 8305-8317Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Soybean phosphatidylcholine (SPC) and glycerol dioleate (GDO) form liquid crystal nanostructures in aqueous environments, and their mixtures can effectively encapsulate active pharmaceutical ingredients (API). When used in a subcutaneous environment, the liquid crystalline matrix gradually hydrates and degrades in the tissue whilst slowly releasing the API. Hydration dependent SPC/GDO phase behavior is complex, non-trivial, and still not fully understood. A deeper understanding of this system is important for controlling its function in drug delivery applications. The phase behavior of the mixture of SPC/GDO/water was studied as a function of hydration and lipid ratio. Small-angle X-ray scattering (SAXS) was used to identify space groups in liquid crystalline phases and to get detailed structural information on the isotropic reverse micellar phase. The reported pseudo ternary phase diagram includes eight different phases and numerous multiphase regions in a thermodynamically consistent way. For mixtures with SPC as the predominant component, the system presents a reverse hexagonal, lamellar and R3m phase. For mixtures with lower SPC concentrations, reverse cubic (Fd3m and Pm3n) as well as intermediate and isotropic micellar phases were identified. By modeling the SAXS data using a core–shell approach, the properties of the isotropic micellar phase were studied in detail as a function of concentration. Moreover, SAXS analysis of other phases revealed new structural features in relation to lipid–water interactions. The new improved ternary phase diagram offers valuable insight into the complex phase behavior of the SPC/GDO system. The detailed structural information is important for understanding what APIs can be incorporated in the liquid crystal structure.

Ort, förlag, år, upplaga, sidor
Royal Society of Chemistry, 2023
Nationell ämneskategori
Fysikalisk kemi
Identifikatorer
urn:nbn:se:mau:diva-63665 (URN)10.1039/d3sm01067h (DOI)37819242 (PubMedID)2-s2.0-85175015955 (Scopus ID)
Tillgänglig från: 2023-11-13 Skapad: 2023-11-13 Senast uppdaterad: 2023-11-13Bibliografiskt granskad
Argatov, I., Krcic, N. & Kocherbitov, V. (2023). Sedimentation of a starch microsphere: What is usually missed and why?. Heliyon, 9(10), Article ID e20257.
Öppna denna publikation i ny flik eller fönster >>Sedimentation of a starch microsphere: What is usually missed and why?
2023 (Engelska)Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 10, artikel-id e20257Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Gravimetric sedimentation is known as a relatively simple method of determining density of spherical particles. When the method is applied to water-swollen starch microparticles of about submillimeter sizes, it becomes evident that a careful selection of the experimental setup parameters is needed for producing accurate testing results. The main reason for this is that the mean particle density is very close to the density of water, and therefore, a dynamic model accounting for the so-called Bassett history force should be employed for describing the unsteady accelerating particle settling. A main novelty of this study consists in deriving a priori estimates for the settling time and distance.

Ort, förlag, år, upplaga, sidor
Cell Press, 2023
Nyckelord
Sedimentation, Starch microspheres, Non-laminar flow, Settling time, Settling distance
Nationell ämneskategori
Vattenbehandling
Identifikatorer
urn:nbn:se:mau:diva-63506 (URN)10.1016/j.heliyon.2023.e20257 (DOI)001084092700001 ()37810817 (PubMedID)2-s2.0-85172256835 (Scopus ID)
Tillgänglig från: 2023-11-07 Skapad: 2023-11-07 Senast uppdaterad: 2023-11-07Bibliografiskt granskad
Tsompou, A. & Kocherbitov, V. (2023). Surface and bulk mechanisms in repeating treatment of solid surfaces by purified water. Heliyon, 9(6), Article ID e17163.
Öppna denna publikation i ny flik eller fönster >>Surface and bulk mechanisms in repeating treatment of solid surfaces by purified water
2023 (Engelska)Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 6, artikel-id e17163Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

To decrease the negative impact of surfactants, the idea of using purified water in washing has been proposed. Previous studies showed that purified water facilitates the roll-up mechanism by promoting electrostatic interactions between the surface and the soil. However, washing mech-anisms can be dependent on the amount of remaining soil.In this work we studied the removal of thin Vaseline films and thicker oil films from hydro-philic surfaces using multiple washing cycles at different temperatures. The Quartz Crystal Mi-crobalance with Dissipation monitoring (QCM-D) and gravimetric analysis were used for thin and thick films respectively. In QCM-D experiments most of the thin film was removed during the first two cycles, while following cycles did not substantially affect washing efficiency; increased temperature facilitated the washing process. Gravimetric analysis showed that the washing of thicker films can be divided into two regimes. During the first, exponential, regime the amount of oil on the surface is high and surface mechanisms, such as roll-up, dominate. Oil droplets are kinetically stabilized in purified water by electrostatic interactions. As the amount of oil on the surface decreases, the second, linear, regime is introduced. The removal of oil occurs by equi-librium bulk mechanisms, where electrostatic interactions are less important.

Ort, förlag, år, upplaga, sidor
Cell Press, 2023
Nyckelord
Washing and cleaning, Water purity, Quartz crystal microbalance with dissipation, monitoring, Temperature, Washing cycles, Mechanisms of washing and cleaning, Emulsification, Olive oil, Surface tension, Entropy, Charge stabilization
Nationell ämneskategori
Teknisk mekanik
Identifikatorer
urn:nbn:se:mau:diva-62433 (URN)10.1016/j.heliyon.2023.e17163 (DOI)001042270500001 ()37484311 (PubMedID)2-s2.0-85162160293 (Scopus ID)
Tillgänglig från: 2023-09-13 Skapad: 2023-09-13 Senast uppdaterad: 2023-09-13Bibliografiskt granskad
Bogdanova, E. & Kocherbitov, V. (2022). Assessment of activation energy of enthalpy relaxation in sucrose-water system: effects of DSC cycle type and sample thermal history. Journal of thermal analysis and calorimetry (Print), 147, 9695-9709
Öppna denna publikation i ny flik eller fönster >>Assessment of activation energy of enthalpy relaxation in sucrose-water system: effects of DSC cycle type and sample thermal history
2022 (Engelska)Ingår i: Journal of thermal analysis and calorimetry (Print), ISSN 1388-6150, E-ISSN 1588-2926, Vol. 147, s. 9695-9709Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The purpose of this study is to critically analyze different methods of calculation of activation energy of relaxation in sucrose-water system from differential scanning calorimetry data. We consider the use of different thermal cycles for calculations together with Moynihan and Kissinger equations. We study the effect of two methods of glass transition temperature determination (half-step and inflection point) on the activation energy values. Along with experimental DSC data, we use the data simulated using Tool-Narayanaswamy-Moynihan model to validate the use of cooling and heating curves and to check the reproducibility of the activation energy calculations. The obtained results show that the thermal cycle with equal cooling and heating rates provides the most reliable data set and the glass transition temperature definition using inflection point rather than half step can be recommended for calculations. Moreover, due to technical reasons, heating rather than cooling scans provide the most reliable results of activation energy calculations. Furthermore, a simple method based on the width of the glass transition region shows reasonable results for single scan experiments. The activation energies of the glass transition in sucrose-water system with different water contents and different thermal histories were studied. Since it is impossible to apply traditional methods based on Moynihan equation for the activation energy evaluation for freeze-dried samples, we propose using another method based on the properties of the recovery peak. Combining the results obtained by different methods, we present a dependence of activation energy in sucrose-water system on water content. The results show that water decreases the activation energy of relaxation process in sucrose matrix.

Ort, förlag, år, upplaga, sidor
Springer, 2022
Nyckelord
DSC, Glass transition, Activation energy, Sucrose, Freeze-dried samples, Tool-Narayanaswamy-Moynihan model
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:mau:diva-50464 (URN)10.1007/s10973-022-11250-6 (DOI)000752728700001 ()
Tillgänglig från: 2022-03-07 Skapad: 2022-03-07 Senast uppdaterad: 2022-09-05Bibliografiskt granskad
Argatov, I., Roosen-Runge, F. & Kocherbitov, V. (2022). Dynamics of post-occlusion water diffusion in stratum corneum. Scientific Reports, 12(1), Article ID 17957.
Öppna denna publikation i ny flik eller fönster >>Dynamics of post-occlusion water diffusion in stratum corneum
2022 (Engelska)Ingår i: Scientific Reports, E-ISSN 2045-2322, Vol. 12, nr 1, artikel-id 17957Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Diffusion of water through membranes presents a considerable challenge, as the diffusivity often depends on the local concentration of water. One particular example with strong biological relevance is the stratum corneum (SC) as the primary permeability barrier for the skin. A simple alternative for the constant diffusivity model is provided by the Fujita's two-parameter rational approximation, which captures the experimentally observed fact that the SC diffusion constant for water increases with increasing the water concentration. Based on Fick's law of diffusion, a one-dimensional concentration-dependent diffusion model is developed and applied for the analysis of both the steady-state transepidermal water loss (TEWL) and the non-steady-state so-called skin surface water loss (SSWL) occurred after removal of an occlusion patch from the SC surface. It is shown that some of the age-related changes in the SSWL can be qualitatively explained by the variation of the dimensionless Fujita concentration-dependence parameter.

Ort, förlag, år, upplaga, sidor
Nature Publishing Group, 2022
Nationell ämneskategori
Fysikalisk kemi
Identifikatorer
urn:nbn:se:mau:diva-56042 (URN)10.1038/s41598-022-22529-x (DOI)000874705000087 ()36289240 (PubMedID)2-s2.0-85140630537 (Scopus ID)
Tillgänglig från: 2022-11-16 Skapad: 2022-11-16 Senast uppdaterad: 2023-08-24Bibliografiskt granskad
Digaitis, R., Falkman, P., Oltner, V., Briggner, L.-E. & Kocherbitov, V. (2022). Hydration and dehydration induced changes in porosity of starch microspheres. Carbohydrate Polymers, 291, 119542-119542, Article ID 119542.
Öppna denna publikation i ny flik eller fönster >>Hydration and dehydration induced changes in porosity of starch microspheres
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2022 (Engelska)Ingår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 291, s. 119542-119542, artikel-id 119542Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Characterization and tuning of the porosity of amorphous starch materials are important for many applications, including controlled release of encapsulated proteins. The porosities of these materials in dry and hydrated states can have different physicochemical origins and properties. Here, porosities of dry cross-linked starch microspheres and their hydration-induced transformations were characterized by small angle X-ray scattering, scanning electron and optical microscopies, thermogravimetric analysis, sorption calorimetry, nitrogen sorption, and helium-pycnometry. The analyses revealed that dry microspheres consist of porous cores with pore diameters below 100 nm and shells which appeared to be denser but contained wider pores (100–300 nm). The outer crust of the microspheres shell is non-porous, which restricts diffusion of nitrogen, water, and ethanol. Partial hydration triggered an irreversible collapse of dry porosity at 12 wt% water. Further hydration resulted in interfacial changes and promoted wet porosity, related to characteristic distances between polymer chains.

Ort, förlag, år, upplaga, sidor
Elsevier, 2022
Nyckelord
Degradable starch microspheres, Cross-linking, Dry porosity, Wet porosity, Water sorption
Nationell ämneskategori
Pappers-, massa- och fiberteknik
Identifikatorer
urn:nbn:se:mau:diva-53308 (URN)10.1016/j.carbpol.2022.119542 (DOI)000798768400007 ()35698372 (PubMedID)
Tillgänglig från: 2022-06-21 Skapad: 2022-06-21 Senast uppdaterad: 2022-12-07Bibliografiskt granskad
Bogdanova, E., Fureby, A. M. & Kocherbitov, V. (2022). Influence of cooling rate on ice crystallization and melting in sucrose-water system. Journal of Pharmaceutical Sciences, 111(7), 2030-2037, Article ID S0022-3549(22)00035-1.
Öppna denna publikation i ny flik eller fönster >>Influence of cooling rate on ice crystallization and melting in sucrose-water system
2022 (Engelska)Ingår i: Journal of Pharmaceutical Sciences, ISSN 0022-3549, E-ISSN 1520-6017, Vol. 111, nr 7, s. 2030-2037, artikel-id S0022-3549(22)00035-1Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The ice crystallization and melting in systems where the equilibrium state is difficult to reach is one of the growing areas in pharmaceutical freeze-drying research. The quality of the final freeze-dried product depends on the parameters of the cooling step, which affect the ice nucleation and growth. In this paper, we present a DSC study of ice crystallization and melting in a sucrose-water system. Using two different types of thermal cycles, we examine the influence of cooling and heating rates on the thermal behavior of sucrose-water solutions with water contents between 50 and 100 wt%.

The DSC results show that low cooling rates provide crystallization at higher temperatures and lead to lower amount of nonfreezing water. Consequently, the glass transition and ice melting properties observed upon heating depend on the cooling conditions in the preceding step. Based on the experimental results, we investigate the reasons for the existence of the two steps on DSC heating curves in sucrose-water systems: the glass transition step and the onset of ice melting. We show that diffusion of water can be the limiting factor for ice growth and melting in the sucrose-water system when the amorphous phase is in a liquid state. In particular, when the diffusion coefficient drops below 10−14 m2/sec, the ice crystals growth or melting becomes strongly suppressed even above the glass transition temperature. Understanding the diffusion limitations in the sucrose-water system can be used for the optimization of the freeze-drying protocols for proteins and probiotics.

Ort, förlag, år, upplaga, sidor
Elsevier, 2022
Nyckelord
Crystallization, Differential Scanning Calorimetry (DSC), Diffusion, Excipients, Glass transition, Sucrose
Nationell ämneskategori
Fysikalisk kemi
Identifikatorer
urn:nbn:se:mau:diva-50055 (URN)10.1016/j.xphs.2022.01.027 (DOI)000817828300018 ()35120964 (PubMedID)
Tillgänglig från: 2022-02-09 Skapad: 2022-02-09 Senast uppdaterad: 2022-08-02Bibliografiskt granskad
Projekt
Polysackarid – vatten interaktioner: sorption, porositet och reologi; Malmö högskola, Biofilms Research Center for Biointerfaces (Upphörd 2017-12-31)Pickering-emulsioner på hud: Effekter av etanol före, under och efter applicering vid varierande omgivningsbetingelser; Malmö universitetKiselbaserade nanoporösa partiklar för läkemedelsformuleringar; Malmö universitetIcke-invasiv monitorering av hudsjukdomars progression och läkning baserat på lågmolekylära biomarkörer; Malmö universitet
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0002-9852-5440

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