Analytical grade organic solvents

All chemicals were purchased from Sigma-Aldrich (St. Louis, MO, USA) and used as received. Analytical grade organic solvents and all other reagents were purchased from Fisher Scientific (Pittsburgh, PA, USA). Gemcitabine was purchased from LC Laboratories (Woburn, MA, USA). PEG-b-PLA was purchased from Advanced Polymer Materials Inc. (Montreal, Canada): the M_n of PEG and PLA was 4000 and 2200 g/mol, respectively; polydispersity index (PDI) 1.05. A549 human lung adenocarcinoma cells and PANC-1 pancreatic adenocarcinoma cells were purchased from ATCC (Manassas, VA, USA) and cultured in RPMI 1640 medium and Dulbecco’s modified Eagle’s medium (DMEM), respectively, supplemented with 10% fetal bovine serum, 100 IU/mL penicillin, 100 μg/mL streptomycin, and 2 mM L-glutamine in a 5% CO₂ incubator at 37 °C. Heparinized Sprague−Dawley rat plasma was purchased from Innovative Research Inc. (Novi, MI, USA).

Paclitaxel (PTX) was purchased from LC Laboratories (Woburn, MA). Oligo(lactic acid)₈ paclitaxel (o(LA)₈-PTX) was synthesized according to our previous report [22 (link)]. PEG-b-PLA was purchased from Advanced Polymer Materials Inc. (Montreal, Canada): M_n of PEG and PLA was 4,000 and 2,200 g/mol, respectively; PDI 1.05. All chemicals were purchased from Sigma-Aldrich (St. Louis, MO) and used as received. Analytical grade organic solvents and all other reagents were purchased from Fisher Scientific (Pittsburgh, PA). 4T1 human breast cancer cell lines were purchased from ATCC (Manassas, VA). 4T1 cells were stably transfected with a luciferase-expressing plasmid pGL4.51 containing the neomycin-resistance gene (Promega, Madison, WI) using lipofectamine 2000 from Invitrogen (Carlsbad, CA) according to the manufacturer’s instructions and our previous report [24 (link)]. D-Luciferin was purchased from Caliper Life Science (Hopkinton, MA). Heparinized Sprague-Dawley rat plasma and human pool plasma were purchased from Innovative Research Inc. (Novi, MI).