Related Experiment Video
Updated: May 30, 2026
Characteristics of Precipitation-formed Polyethylene Glycol Microgels Are Controlled by Molecular Weight of Reactants
Published on: December 23, 2013
Polyethylene glycol behaves like weak organic solvent.
Atsushi Hirano1, Kentaro Shiraki, Tsutomu Arakawa
1Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki, Japan.
Polyethylene glycol (PEG) solutions affect amino acid solubility, acting like weak organic solvents. While PEG generally decreases solubility, it favorably stabilizes aromatic amino acid side chains.
Area of Science:
- Biochemistry
- Physical Chemistry
- Chemical Engineering
Background:
- Polyethylene glycol (PEG) is known to influence protein solubility via molecular crowding.
- PEG's behavior also resembles that of organic solvents, suggesting alternative interaction mechanisms.
Purpose of the Study:
- To investigate the solubility of glycine and various amino acids in PEG solutions.
- To elucidate the interaction mechanisms between PEG and amino acid side chains.
Main Methods:
- Assessing the solubility of glycine, aliphatic, and aromatic amino acids in PEG400, PEG4000, and PEG20000 solutions.
- Analyzing the free energy changes associated with amino acid side chain interactions in PEG4000.
Main Results:
- PEG solutions decreased glycine solubility, but to a lesser extent than common organic solvents.
- PEG4000 exhibited weak unfavorable interactions with aliphatic side chains but significantly stabilized aromatic side chains.
- PEG20000 induced phase separation of glycine under saturated conditions, unlike PEG400 and PEG4000.
Conclusions:
- PEG acts as a weak organic solvent, destabilizing polar/charged groups and stabilizing aromatic groups.
- The size of PEG influences its interaction with amino acids, with PEG20000 showing unique phase separation behavior.
More Related Videos
15:33Microwave-assisted Functionalization of Poly(ethylene glycol) and On-resin Peptides for Use in Chain Polymerizations and Hydrogel Formation
Published on: October 29, 2013
07:05Microwave-Assisted Extraction of Phenolic Compounds and Antioxidants for Cosmetic Applications Using Polyol-Based Technology
Published on: August 23, 2024
Related Concept Videos
03:37Molecular Shape and Polarity
01:20Types of Step-Growth Polymers: Polyesters
Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the polymer...
02:17Physical Properties of Ethers
An ether molecule has a net dipole moment due to the polarity of C–O bonds. Subsequently, boiling points of ethers are lower than those of alcohols of comparable molecular weight and slightly higher than those of hydrocarbons of comparable molecular weight (Table 1).
Ethers can act as hydrogen bond acceptors, making them more water-soluble than hydrocarbons, but since ethers cannot act as hydrogen bond donors, they are much less soluble in water than alcohols. Ethers are considered...
02:12Solvating Effects
02:32Physical Properties of Alcohols and Phenols
Alcohols possess a higher boiling point than aliphatic hydrocarbons of similar...
00:56Extraction: Advanced Methods