Folic acid (FA) is one of the B vitamins (vitamin B9) and is an essential nutrient. Folic acid deficiency may lead to symptoms such as headaches, depression, forgetfulness and other cognitive deficits, nerve damage, heart palpitations and pregnancy complications. Folic acid is recognized and internalized by folate receptors, which are overexpressed on the cell surface of certain tumor types.

Cholesterol (CLS) is a lipid that is an integral component of all animal cell membranes. It is required to maintain both membrane structural integrity and fluidity, and thus is essential for all animal life. Cholesterol also serves as a precursor for the biosynthesis of steroid hormones and bile acids and is involved in many other biological functions.

PEG conjugates of folic acid and cholesterol are valuable tools for the delivery of drugs and other molecules, such as fluorophores. While the folic acid moiety is commonly used to target folate receptors, PEG-cholesterol conjugates promote internalization via clathrin-independent pathways into endosomes and the Golgi apparatus. Furthermore, the PEG chain drastically improves solubility as well as physical stability and half-life in vivo.

Iris Biotech now offers many variants of PEG-conjugates of FA and CLS, equipped with a wide variety of functional groups to suit your needs (amine, NHS ester, azide, thiol etc.). Moreover, each of these derivatives is offered with PEG chains of different lengths, ranging from 1’000 Da to 20’000 Da. We also offer cross-linked PEG-conjugates of both cholesterol and folic acid (FA-PEG-CLS), which combine the benefits of those moieties.

→ Find all of our PEG-Conjugates, as well as many other PEGylation reagents, in our Webshop!

References

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