Products > Optimize Reagents > Optimize - Polymers > Polyethylene glycol monomethyl ether 5,000

Polyethylene glycol monomethyl ether 5,000


  • Crystallization grade Polyethylene glycol monomethyl ether 5,000 for formulating screens or for optimization


  •  Sterile filtered solution
  • Formulated in Type 1+ ultrapure water: 18.2 megaohm-cm resistivity at 25°C, < 5 ppb Total Organic Carbon, bacteria free (<1 Bacteria (CFU/ml)), pyrogen free (<0.03 Endotoxin (EU/ml)), RNase-free (< 0.01 ng/mL) and DNase-free (< 4 pg/µL)


Polyethylene glycol 5,000 monomethyl ether

Synonyms: Methoxy poly(ethylene) glycol 5,000 or mono-Methyl polyethylene glycol 5,000 or PEG MME 5,000, or MPEG 5,000
CAS Number [9004-74-4]
Average Mn 5,000
EC Number 215-801-2
RTECS PE8271000
MDL Number MFCD00084416
PubChem Substance ID 24887753
Melting Point (Starting Material) 59°C
Appearance (Starting Material) Fine, white flakes

Aldehyde None detected
Peroxide None detected

Measured Conductivity range: 19.8 - 24.1 µS/cm at 25°C
Measured Refractive Index range: 1.40164 - 1.40209 at 20°C




50% w/v Polyethylene glycol monomethyl ether 5,000


200 mL



Support Material(s)

Certificate Of Analysis


1. Poly(ethylene) glycol monomethyl ethers - an alternative to poly(ethylene) glycols in protein crystallization. A. M. Brzozowski and S. P. Tolley. Acta Cryst. (1994). D50, 466-468.

2. Crystallization of a Humicola lanuginosa lipase-inhibitor complex with the use of polyethylene glycol monomethyl ether. A. M. Brzozowski. Acta Cryst. (1993). D49, 352-354.

3. Crystallization and preliminary crystallographic analysis of the transcriptional regulator RfaH from Escherichia coli and its complex with ops DNA. M. N. Vassylyeva, V. Svetlov, S. Klyuyev, Y. D. Devedjiev, I. Artsimovitch and D. G. Vassylyev. Acta Cryst. (2006). F62, 1027-1030.