Preparation and characterization of heparin hexasaccharide library with N-unsubstituted glucosamine residues

Harnessing the potential of de-sulfated heparin for targeted drug delivery: A three-component approach exemplified by conjugation with galactose and paclitaxel

Heparin, an anticoagulant with a century-long history of use, has been investigated over the past decade as a potential drug delivery vehicle. Despite its safety and efficacy, its interactions with many proteins through specific sulfate patterns can complicate drug delivery by mediating diverse biological functions. Here, we present the synthesis of a three-component drug delivery system comprising de-sulfated heparin as the carrier, galactose as the targeting moiety, and paclitaxel as the therapeutic drug. Removal of sulfates eliminated most of its anticoagulant effects in all intermediates. Through coupling with galactose and paclitaxel, the system improved the solubility of the drug and achieved selective targeting and efficient drug delivery to HepG2 cells, a liver carcinoma cell line with high galactose receptor expression. While the three-component system exhibited a slightly higher IC50 value than native paclitaxel, demonstrating its efficacy as a drug carrier, the IC50 value for the normal human liver cell line QSG7701 was significantly higher, indicating its selectivity and safety. Our study introduces a novel approach utilizing desulfated heparin as a carrier, warranting further investigation to unlock its potential in targeted drug delivery strategies.

Preparation and characterization of partial de-O-sulfation of heparin oligosaccharide library

The O-sulfation, including 2-O- and 6-O-sulfation, in heparan sulfate (HS) have important biological and pathophysiological roles. Therefore, the ability to chemically generate a series of oligosaccharides, which have a similar structure to the naturally-occurring, 2-O- and 6-O-sulfating oligosaccharides from HS, would greatly contribute to investigating their natural role in HS. In this study, a heparin oligosaccharide library, including dp2, dp4 and dp6, were prepared from the chemical modification of the fully sulfated dp2, dp4 and dp6. Chemical reaction conditions were optimized to generate different patterns of 2-O- and 6-O-sulfated oligosaccharides, then the disaccharide composition and structure of the library was detected by high-performance liquid chromatography-ion trap/time-of-flight mass spectrometry (LC-IT-TOF/MS) analysis. This provides a foundation for further structural and functional studies of O-sulfated groups in HS.