title: Modification of encapsulation pressure of reverse micelles in liquid ethane.
abstract: Encapsulation within reverse micelles dissolved in low viscosity fluids offers a potential solution to the slow tumbling problem presented by large soluble macromolecules to solution NMR spectroscopy. The reduction in effective macromolecular tumbling is directly dependent upon the viscosity of the solvent. Liquid ethane is of sufficiently low viscosity at pressures below 5000 psi to offer a significant advantage. Unfortunately, the viscosity of liquid ethane shows appreciable pressure dependence. Reverse micelle encapsulation in liquid ethane often requires significantly higher pressures, which obviates the potential advantages offered by liquid ethane over liquid propane. Addition of co-surfactants or co-solvents can be used to manipulate the minimum pressure required to obtain stable, well-behaved solutions of reverse micelles prepared in liquid ethane. A library of potential additives is examined and several candidates suitable for use with encapsulated proteins are described.
authors.affiliation: Graduate Group in Biochemistry & Molecular Biophysics and Department of Biochemistry & Biophysics, University of Pennsylvania, Philadelphia, PA 19104-6059, United States.
authors.forename: Ronald W
authors.initials: RW
authors.lastname: Peterson
authors.forename: Nathaniel V
authors.initials: NV
authors.lastname: Nucci
authors.forename: A Joshua
authors.initials: AJ
authors.lastname: Wand
mesh_terms: D000438:Alcohols / Q000737:chemistry; D000465:Algorithms; D002245:Carbon Dioxide / Q000737:chemistry; D002246:Carbon Disulfide / Q000737:chemistry; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D003080:Cold Temperature; D004143:Dioctyl Sulfosuccinic Acid; D004980:Ethane / Q000737:chemistry*; D007202:Indicators and Reagents; D008823:Micelles; D011312:Pressure; D011407:Propane; D011506:Proteins / Q000737:chemistry*; D012996:Solutions; D012997:Solvents; D013386:Succinates / Q000737:chemistry; D013501:Surface-Active Agents; D014783:Viscosity
chemical_list: D000438:Alcohols; D002593:Cetrimonium Compounds; D007202:Indicators and Reagents; D008823:Micelles; D011506:Proteins; D012996:Solutions; D012997:Solvents; D013386:Succinates; D013501:Surface-Active Agents; D004143:Dioctyl Sulfosuccinic Acid; D002245:Carbon Dioxide; D004980:Ethane; D002246:Carbon Disulfide; D011407:Propane; D000077286:Cetrimonium