• 96IndividualCrystallizationConditions
• UltraPurePEGs-USPGradePolydisperse
• PEGCocktail-5PEGsineachcondition
• pHmeasuredandrecordedforboththestockbuffersandfinalcrystallizationconditions

ThePurePEGsCrystallizationScreenfeaturesconditionsthateachcontainamixtureofpurifiedpolyethyleneglycols,rangingfrom300MWto8000MW.Atatotalconcentrationof22.5%PEGcombinedwithvarioussaltsandbuffers,theconditionsaredesignedtospanawidecrosssectionofPEGcrystallizationspace.ManysuccessfulcrystallizationconditionscomprisecombinationsofPEGsandsaltsadjustedtoaparticularpH.However,thenecessitytosampleabroadrangeofPEGprecipitantsduringinitialsparsematrixscreeningrenderscomprehensivePEGscreeningatthisstagehighlychallenging.Interestingly,thereisevidencetosuggestthatproteinconcentrationconditionsidentifiedusingaparticularPEGcanberepeatedwhenusingmixturesofPEGsasasingleprecipitant.Consequently,amorerationalscreeningstrategyshouldbetousemixturesofPEGsratherthanconditionscontainingindividualPEGs.InVaporDiffusionexperiments,thisapproachsignificantlyminimizesthenumberofconditionstobesampledandthevolumeofproteinnecessarytoexplorePEGcrystallizationspace.Citations:

1. J.Newmanetal.ActaCrystallogrD.61,1426(2005)
2. R.Pageetal.ActaCrystallogD.59,1028(2003)
3. J.W.Woohetal.ActaCrystallogD.59,769(2003)
4. J.T.Bukrinskyetal.JApplCryst.34,533(2001)

FormerlyreferencedasMD18-05andMD18-05Tonourwebsite.