초록 |
In order to increase drug payload and improve tumor targeting efficiency, we prepared gold nanoclusters (AuNCs) for anti-tumor drug delivery. Small size bare AuNPs were surface modified with azido groups by introducing N3-PEG-SH, followed by complete coverage of the whole surface with HS-PEG-COOH (azido/PEG@AuNPs). Meanwhile, MMP-2 cleavable peptide was terminated by alkyne-PEG4-maleimide (al-pep-al). Thereafter, azido/PEG@AuNP and al-pep-al were clicked into AuNCs in the presence of sodium ascorbate and CuSO4 in DW and the size change was monitored. To confirm the dissociation property, the solvent of AuNCs was changed to PBS and then MMP-2 was added and incubated in 37 °C. This AuNCs is promising for drug transportation as it not only has high drug loading capacity but tunable size in accordance to the molar ratio of azido group to al-pep-al, thus decrease normal cell uptake but enhance tumor site permeation, where MMP-2 is abundant and undergo dissociation. |