Objective: To prepare camptothecin-loaded core-shell type nano-micelles (polyethylene glycol-poly benzyl-L-glutamate

PEG-PBLG) and investigate its drug-loaded characteristics and in vitro properties. Method: Camptothecin-loaded(CPT) nano-micelles with PEG-PBLG was prepared by dialysis and freeze-drying method

in vitro release characteristics of CPT/PEG-PBLG nano-micelles was measured by UV

and its cytotoxicity for HepG-2 cell was investigated. Result: Camptothecin could be entrapped in PEG-PBLG nano-micelles

drug loading content of EG-5 was 11.13%

whose molar ratio of BLG block was 35%;CPT/PEG-PBLG nano-micelles had in vitro burst and sustained release profile

it could accelerate release speed in alkaline medium

cumulative release rate of EG-5 micelles was 60.34% at pH 1.1

but it was 73.72% at pH 10.0;When the concentration of camptothecin ≤50 mg·L-1

CPT/PEG-PBLG nano-micelles displayed much less cell cytotoxicity than the same concentration of camptothecin positive group(P<0.01). Conclusion: Preparation technology of CPT/PEG-PBLG nano-micelles was simple and safe without pollution for environment

it would reduce cytotoxicity of camptothecin for clinic treatment value of tumor.