PEG/Ion 400 is a crystallization screen for membrane and soluble biological macromolecules.

•Reagent formulation developed at Hampton Research
•Screen a profile of anions, cations, multivalent ions, and neutralized organic acids at varying pH levels in the presence of Polyethlene glycol 400
•pH range 5 - 9
•Buffer free formulation
•Compatible with lipidic cubic phase (LCP), vapor diffusion, microbatch, and free interface diffusion

PEG/Ion 400 is a crystallization reagent kit designed to provide a rapid screening method for the crystallization of membrane and soluble biological macromolecules.

Most G protein-coupled receptors (GPCRs) have been crystallized in Polyethylene glycol (PEG) 400 based reagents1. PEG/Ion 400 is designed as a 96 reagent crystallization screen that is compatible with the Lipidic Cubic Phase (LCP).

PEG/Ion 400 is supplied in a sterile, polypropylene 96 Deep Well block, each reservoir containing 1 ml of sterile filtered reagent. The block is compatible with robotic and multi-channel pipet liquid handling systems and is heat sealed using a special polypropylene backed film. Each PEG/Ion 400 is supplied with an adhesive sealing film which can be used to seal the block after removing the heat seal.

The screen combines a single concentration (30% v/v) of high purity Polyethylene glycol 400 and 48 different high purity salts, comprising both anions (malate, malonate, nitrate, phosphate, succinate, sulfate, tartrate, and thiocyanate) and cations (ammonium, cadmium, calcium, ethylammonium, lithium, magnesium, nickel, potassium, sodium, tetraethylammonium, and zinc) in two concentrations (0.1 and 0.4 M) which due to their unique pH characteristics also affords a reasonable pH screen (approximate pH range of 4 to 9.5). The primary screen variables are PEG, ion type, ionic strength, salt concentration, and pH.

HR2-460 PEG/Ion 400 1 mL, Deep Well block format


1. Successful Strategies to Determine High-Resolution Structures of GPCRs. Xiang J, Chun E, Liu C, Jing L, Al-Sahouri Z, Zhu L, Liu W. Trends Pharmacol Sci. 2016 Dec;37(12):1055-1069.

2. Crystal structure of rhodopsin bound to arrestin by femtosecond X-ray laser. Kang Y, Zhou XE, Gao X, et al. Nature. 2015;523(7562):561-567. doi:10.1038/nature14656.

3. Development of an Automated High Throughput LCP-FRAP Assay to Guide Membrane Protein Crystallization in Lipid Mesophases. Fei Xu, Wei Liu, Michael A. Hanson, Raymond C. Stevens, and Vadim Cherezov. Cryst. Growth Des., 2011, 11 (4), pp 1193-1201.

4. A comprehensive review of the lipid cubic phase or in meso method for crystallizing membrane and soluble proteins and complexes. Martin Caffrey. Acta Crystallogr F Struct Biol Commun. 2015 Jan 1; 71(Pt 1): 3-18.