{"title":"水合磷脂多层膜层间水的拉曼光谱表征","authors":"E.A. Dobrynina, S.V. Adichtchev, N.V. Surovtsev","doi":"10.1016/j.chemphyslip.2025.105529","DOIUrl":null,"url":null,"abstract":"<div><div>The properties of phospholipid bilayers, which are important in various biophysical and biomedical studies, critically depend on the hydration of the lipid bilayer. Interbilayer water in multilamellar vesicles or planar multilayers is a very convenient object for studying the interfacial lipid-water interaction. However, many parameters of the interbilayer water remain incompletely studied, and in some cases different experimental methods yield different parameters of interbilayer water. Here, we developed a Raman spectroscopy method for characterizing interbilayer water in multilayer phospholipid samples. This method was applied to one saturated (DPPC) and one unsaturated (DOPC) phospholipid hydrated at high relative humidity and studied over a wide temperature range. It was found that although above the freezing point of water the OH stretching spectra of interbilayer water were similar to those of bulk water, only about one-fifth of the interbilayer water crystallized at the lowest experimental temperature (110 K). In combination with Raman spectra of aqueous suspensions of phospholipids of known compositions, the number of interbilayer H<sub>2</sub>O molecules per lipid molecule (hydration number) was determined. The hydration number was found for the ordered (gel) and disordered (fluid) phases of hydrated phospholipid bilayers at different temperatures and several relative humidities. The results were compared with values of the hydration number obtained by other methods, and an interpretation was proposed that takes into account the fractions of the free and non-free (perturbed) interbilayer water.</div></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":"271 ","pages":"Article 105529"},"PeriodicalIF":2.8000,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Raman spectroscopy characterization of interbilayer water of hydrated phospholipid multibilayers\",\"authors\":\"E.A. Dobrynina, S.V. Adichtchev, N.V. Surovtsev\",\"doi\":\"10.1016/j.chemphyslip.2025.105529\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The properties of phospholipid bilayers, which are important in various biophysical and biomedical studies, critically depend on the hydration of the lipid bilayer. Interbilayer water in multilamellar vesicles or planar multilayers is a very convenient object for studying the interfacial lipid-water interaction. However, many parameters of the interbilayer water remain incompletely studied, and in some cases different experimental methods yield different parameters of interbilayer water. Here, we developed a Raman spectroscopy method for characterizing interbilayer water in multilayer phospholipid samples. This method was applied to one saturated (DPPC) and one unsaturated (DOPC) phospholipid hydrated at high relative humidity and studied over a wide temperature range. It was found that although above the freezing point of water the OH stretching spectra of interbilayer water were similar to those of bulk water, only about one-fifth of the interbilayer water crystallized at the lowest experimental temperature (110 K). In combination with Raman spectra of aqueous suspensions of phospholipids of known compositions, the number of interbilayer H<sub>2</sub>O molecules per lipid molecule (hydration number) was determined. The hydration number was found for the ordered (gel) and disordered (fluid) phases of hydrated phospholipid bilayers at different temperatures and several relative humidities. The results were compared with values of the hydration number obtained by other methods, and an interpretation was proposed that takes into account the fractions of the free and non-free (perturbed) interbilayer water.</div></div>\",\"PeriodicalId\":275,\"journal\":{\"name\":\"Chemistry and Physics of Lipids\",\"volume\":\"271 \",\"pages\":\"Article 105529\"},\"PeriodicalIF\":2.8000,\"publicationDate\":\"2025-07-30\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Chemistry and Physics of Lipids\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0009308425000659\",\"RegionNum\":3,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"BIOCHEMISTRY & MOLECULAR BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemistry and Physics of Lipids","FirstCategoryId":"99","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0009308425000659","RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
Raman spectroscopy characterization of interbilayer water of hydrated phospholipid multibilayers
The properties of phospholipid bilayers, which are important in various biophysical and biomedical studies, critically depend on the hydration of the lipid bilayer. Interbilayer water in multilamellar vesicles or planar multilayers is a very convenient object for studying the interfacial lipid-water interaction. However, many parameters of the interbilayer water remain incompletely studied, and in some cases different experimental methods yield different parameters of interbilayer water. Here, we developed a Raman spectroscopy method for characterizing interbilayer water in multilayer phospholipid samples. This method was applied to one saturated (DPPC) and one unsaturated (DOPC) phospholipid hydrated at high relative humidity and studied over a wide temperature range. It was found that although above the freezing point of water the OH stretching spectra of interbilayer water were similar to those of bulk water, only about one-fifth of the interbilayer water crystallized at the lowest experimental temperature (110 K). In combination with Raman spectra of aqueous suspensions of phospholipids of known compositions, the number of interbilayer H2O molecules per lipid molecule (hydration number) was determined. The hydration number was found for the ordered (gel) and disordered (fluid) phases of hydrated phospholipid bilayers at different temperatures and several relative humidities. The results were compared with values of the hydration number obtained by other methods, and an interpretation was proposed that takes into account the fractions of the free and non-free (perturbed) interbilayer water.
期刊介绍:
Chemistry and Physics of Lipids publishes research papers and review articles on chemical and physical aspects of lipids with primary emphasis on the relationship of these properties to biological functions and to biomedical applications.
Accordingly, the journal covers: advances in synthetic and analytical lipid methodology; mass-spectrometry of lipids; chemical and physical characterisation of isolated structures; thermodynamics, phase behaviour, topology and dynamics of lipid assemblies; physicochemical studies into lipid-lipid and lipid-protein interactions in lipoproteins and in natural and model membranes; movement of lipids within, across and between membranes; intracellular lipid transfer; structure-function relationships and the nature of lipid-derived second messengers; chemical, physical and functional alterations of lipids induced by free radicals; enzymatic and non-enzymatic mechanisms of lipid peroxidation in cells, tissues, biofluids; oxidative lipidomics; and the role of lipids in the regulation of membrane-dependent biological processes.