Near-infrared activatable phthalocyanine-poly-L-glutamic acid conjugate: increased cellular uptake and light-dark toxicity ratio toward an effective photodynamic cancer therapy

A phthalocyanine-poly-L-glutamic acid (PGA) conjugate (1-PG) retained high absorptivity in the near-infrared (NIR) region, demonstrated good singlet oxygen generation efficiency, increased uptake by 4 T1 breast cancer cells via clathrin-mediated endocytosis, and enhanced photocytotoxic efficacy. The conjugate also displays a high light-dark toxicity ratio, an important feature for the reduction of dark toxicity and unwanted side effects.226