D.R. Absolom , C.J. Van Oss , W. Zingg , A.W. Neumann
{"title":"Determination of surface tensions of proteins II. Surface tension of serum albumin, altered at the protein-air interface","authors":"D.R. Absolom , C.J. Van Oss , W. Zingg , A.W. Neumann","doi":"10.1016/0005-2795(81)90050-7","DOIUrl":null,"url":null,"abstract":"<div><p>Serum albumin, which itself has a surface tension of ⋍70.3 erg/cm<sup>2</sup>, when dissolved in water lowers the surface tension of water from 72.5 to ⋍50 erg/cm<sup>2</sup>, as measured by a variety of means, including the pendant drop, the Wilhelmy plate and the platinum ring methods. Equally low and even lower surface tensions are found with the contact angle method, on a thin layer of albumin that had been adsorbed onto a low energy surface and subsequently exposed to air. Surface tensions of drops of albumin solutions varying in concentration from 0.01 to 5.5% (w/v) yielded, with a contact angle method, values that only varied between 67 and 61 erg/cm<sup>2</sup>. With the pendant drop, the Wilhelmy plate and the platinum ring methods, one essentially measures the surface tension at the air-liquid interface, at which proteins tend to adsorb, and where reversible or irreversible reorientation can be expected. The same holds for a thin layer of protein adsorbed onto a low energy surface, exposed to air. Thus, when through the very act of surface tension measurement, or after adsorbing protein onto a substrate, protein is exposed at the air-liquid interface, it apparently loses the pronounced hydrophilicity characteristic of its native hydrated state and manifests through reorientation a much more hydrophobic tertiary configuration.</p></div>","PeriodicalId":100165,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Protein Structure","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1981-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0005-2795(81)90050-7","citationCount":"56","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biochimica et Biophysica Acta (BBA) - Protein Structure","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0005279581900507","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 56
Abstract
Serum albumin, which itself has a surface tension of ⋍70.3 erg/cm2, when dissolved in water lowers the surface tension of water from 72.5 to ⋍50 erg/cm2, as measured by a variety of means, including the pendant drop, the Wilhelmy plate and the platinum ring methods. Equally low and even lower surface tensions are found with the contact angle method, on a thin layer of albumin that had been adsorbed onto a low energy surface and subsequently exposed to air. Surface tensions of drops of albumin solutions varying in concentration from 0.01 to 5.5% (w/v) yielded, with a contact angle method, values that only varied between 67 and 61 erg/cm2. With the pendant drop, the Wilhelmy plate and the platinum ring methods, one essentially measures the surface tension at the air-liquid interface, at which proteins tend to adsorb, and where reversible or irreversible reorientation can be expected. The same holds for a thin layer of protein adsorbed onto a low energy surface, exposed to air. Thus, when through the very act of surface tension measurement, or after adsorbing protein onto a substrate, protein is exposed at the air-liquid interface, it apparently loses the pronounced hydrophilicity characteristic of its native hydrated state and manifests through reorientation a much more hydrophobic tertiary configuration.