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mPEG-MAL, MW 40k

mPEG-MAL, MW 40k

Catalog No: PSB-238
Product Name: mPEG-MAL, MW 40k
In Stock: Yes
SKUProduct Name
mPEG-MAL, MW 40k - 5g
mPEG-MAL, MW 40k - 10g
mPEG-MAL, MW 40k - 1g
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mPEG-Maleimide is a linear monofunctional methyl ether PEG with a reactive maleimide group. Maleimide (MAL) selectively reacts with free thiol, sulfhydryl, or mercapto group via Michael addition to form a stable carbon sulfur bond. mPEG-MAL is useful for site specific protein and peptide modification. The thiol group to react with mPEG-Maleimide needs to be in the form of free thiol. A reducing reagent DTT and preferably TCEP (without the need to remove excessive TCEP) enhances the thiol reactivity.


Molecular weight: MW of PEG was measured by MALDI-MS or GPC. PDI (polydispersity index) of our linear PEG is 1.02-1.05 with very narrow MW distribution. The number of repeating ethylene oxide units (CH2CH2O) or the degree of polymerization is calculated dividing the PEG MW by 44 (44 is the molecular mass of one repeating unit).

Solubility: Soluble in water and aqueous buffer, chloroform, methylene chloride, DMF, DMSO, and less soluble in alcohol, toluene. Not soluble in ether.

Density: PEG density is approximately 1.125 g/mL

Physical form: PEG products generally appear as white or off-white powder, and for very low MW linear PEG such as MW 1k or less, it may appear as wax-like, semi-solid material due to the low MW and the type of functional groups.

Storage condition: PEG product shall be stored in the original form as received in a freezer at -20C or lower for long term storage. Stock solution of PEG reagents that do not contain oxygen or moisture sensitive functional groups may be temporarily stored in a refrigerator or ambient temperature for multiple days. Stock solution should avoid repeated freeze-and-thaw cycles. See Documents section for detailed storage and handling conditions.


1. Structural and Biochemical Consequences of Disease-Causing Mutations in the Ankyrin Repeat Domain of the Human TRPV4 Channel, Biochemistry, 2012, 51 (31), 6195-6206,  Text.

2.  The holin of bacteriophage lambda forms rings with large diameter, Molecular Microbiology, 09/2008; 69(4):784-793,  Text.

3. In vitro folding of KvAP, a voltage gated K+ channel, Biochemistry. 2011 6; 50(48): 10442-10450,  Text.

4.  Structure of the lethal phage pinhole, Proc Natl Acad Sci USA. 2009;106(45), 18966-71,  Text.

5. A Computationally Designed Inhibitor of an Epstein-Barr Viral Bcl-2 Protein Induces Apoptosis in Infected Cells, Cell, Issue 7, 2014, Pages 1644-1656,  Text.

6. BAK ÃŽ ±6 permits activation by BH3-only proteins and homooligomerization via the canonical hydrophobic groove, PNAS, 2017  vol. 114  no. 29  7629-7634, Text.

7. Engineering Thiolated Surfaces with Polyelectrolyte Multilayers, DOI: 10.1021/acsami.8b15514, 2018, Text.

8.  Trojan Horse for Light-Triggered Bifurcated Production of Singlet Oxygen and Fenton-Reactive Iron within Cancer Cells. Biomacromolecules. 2017 Dec 14;19(1):178-87.  Text.

9.  BAX Activation: Mutations Near Its Proposed Non-canonical BH3 Binding Site Reveal Allosteric Changes Controlling Mitochondrial Association, Cell Reports, 2019, 27(2), 359. DOI:  10.1016/j.celrep.2019.03.040

10.  Reversible Diels–Alder and Michael Addition Reactions Enable the Facile Postsynthetic Modification of Metal–Organic Frameworks, Inorg. Chem.  2021, 60, 7, 4397–4409, Text.

11.  BAX mitochondrial integration is regulated allosterically by its α1−α2 loop, Cell Death & Differentiation,  volume  28, pages3270–3281 (2021), Text.

Click here  to view an expanded list of hundreds of publications citing Creative PEGWorks products.


 Technical Information_Linear PEG Products

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