Thermo Scientific Pierce CL(PEG)12, or carboxy-PEG12-lipoamide, is a carboxyl- and bidentate thiol-terminated compound that contains a 4-unit polyethylene glycol (PEG) spacer and is used to modify quantum dots, and silver or gold surfaces and particles.
CL(PEG)12 is a bidentate thiol-terminated and carboxylic acid pegylation reagent. The PEG compound has a defined molecular weight and spacer length and is useful for modifying surfaces such quantum dots, self-assembled monolayers and magnetic particles. Functionalization of solid surfaces with this polyethylene glycol reagent provides carboxylate "handles" for protein immobilization via EDC crosslinking and significantly reduces nonspecific protein binding and provides.
- Metal-binding – terminal bidentate thiol reacts spontaneously with silver, gold and other metal surfaces to form strong dative bonds
- Carboxylate – terminal carboxylic acid group allows conjugation to amine-containing affinity ligands using carbodiimide (EDC) and Sulfo-NHS crosslinking chemistry
- Polyethylene glycol – PEG groups are flexible, non-immunogenic, hydrophilic, and significantly reduce nonspecific binding of surfaces for protein methods
- Spacer arm – 12-unit PEG spacer makes the reagent nearly 56 angstroms long, minimizing steric hindrance for protein immobilization and binding assays
Chemical structure and properties of CL(PEG)12:
- Alternative name: Carboxy-PEG12-Lipoamide
- Chemical name: 45-(1,2-dithiolan-3-yl)-41-oxo-4,7,10,13,16,19,22,25,28,31,34,37-dodecaoxa-40-azapentatetracontan-1-oic acid
- Chemical formula: C35H67NO15S2
- Molecular weight: 806.03
- Spacer arm: 55.5 angstroms
- Form: yellow solid
- Solubility: dissolve in DMSO or DMF for use
The use of CL(PEG)12 with ML(PEG)4 in surface modification can form a hydrophilic “lawn” of methyl ether-terminated PEGs with periodic exposed carboxy -containing PEGs. The exposed carboxylic acid groups can be coupled to affinity ligands using the carbodiimide coupling reaction with EDC and sulfo-NHS.
|Modification of metal surfaces with ML(PEG)4 and CL(PEG)12 pegylation reagents.
Typical PEG reagents contain heterogeneous mixtures of different PEG chain lengths; however, our PEG reagents are homogenous compounds of defined molecular weight and spacer length, providing precision in optimizing modification applications.
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- Lin, P-C., et al. (2006). Ethylene glycol-protected magnetic nanoparticles for a multiplexed immunoassay in human plasma. Small 2(4):485-9.
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- Verma, A. and Rotello, V.M. (2005). Surface recognition of biomacromolecules using nanoparticle receptors. Chem Commun 3:303-12.
- Kidambi, S., et al. (2004). Selective depositions on polyelectrolyte multilayers: self-assembled monolayers of m-dPEG acid as molecular template. J Am Chem Soc 126:4697-03.
Protein PEGylation technical guide (and PEG reagent selection guide)