Polymeric micelles with photo-activated proton release behavior for enhanced tumor extracellular pH targeting and drug release

摘要: Abstract The extracellular pH (6.5–7.2) of most tumors varies only slightly from those the normal tissues and blood (pH 7.4). For enhanced tumor targeting, Polymeric micelles (PM) based on 1-pyrenemethanol-modified carboxymethyl chitosan conjugate with succinyl linkage (PCMC) were constructed to regulate pH. TEM observation showed that had a core–shell structure an average diameter 210 ± 10.7 nm. Dynamic light scattering studies indicated good in vitro stability. However, upon exposure UV stimuli, were disrupted accompanied by proton release, which could trigger aggregation non-irradiated at 6.0. intensity irradiation time obvious influence the proton release. release mechanism may be attributed photosolvolysis ester bond linked pyrenemethyl groups polymeric side chains, was proved UV–Vis 1H NMR. Paclitaxel (PTX) entrapped into core as model drug, accumulative rate 3.5% within 12 h 7.4. 6.8 (365 nm, 500 mW cm−2) for 4 min subsequently mixing aliquot drug-loaded sample, drug significant inhibition against HeLa cells observed. study provided new strategy design targeted nanocarriers delivery.