Role of a long-chain alkyl group in sulfated alkyl oligosaccharides with high anti-HIV activity revealed by SPR and DLS.

Although a long-chain alkyl group in sulfated oligosaccharides can enhance the anti-HIV activity, the exact mechanism is unclear. To elucidate the role of the long-chain alkyl group, its interaction with a liposome (100 nm) as a HIV model was investigated by surface plasmon resonance and dynamic light scattering. The newly synthesized sulfated 1-(decadecyl-1, 2, 3-triazole)-1-deoxy- maltoheptaoside bearing the long-chain alkyl group was found to interact with the liposome. The particle size increased and the ζ potential was negative, indicating that the sulfated alkyl maltoheptaoside was attached to the liposome by the long-chain alkyl group and the fixed sulfated maltoheptaoside moiety was covered on the liposome. Thus, the long-chain alkyl group penetrates and is fixed into the lipid bilayer of HIV and the sulfated maltoheptaose moiety with negatively charged sulfate groups was electrostatically interacted with HIV gp120 molecule with positively charged amino acids to achieve the inhibition of HIV infection.