Glucose oxidase-loaded colloidal stable WS nanobowls for combined starvation/photothermal therapy of colorectal tumors.

Glucose is used as an important nutrient to support cell growth. The glucose oxidase (GOx) can transform glucose into gluconic acid and toxic HO, which can be used for tumor starvation therapy. However, the leakage of GOx may cause severe side effects to the normal tissue. To prevent the accidental leakage of GOx, this study proposes the chemical modification of GOx on the photothermal transducing agent surface, to realize the safe and combined starvation and photothermal therapy of colorectal tumors. Polyvinylpyrrolidone (PVP)-modified WS nanobowls (WS-PVP) as a photothermal transducing agent were produced using a one-pot preparation method. Then, α-lipoic acid (LA) molecules were immobilized at the sulfur-deficient sites on the surface of WS nanobowls to afford the chemical loading of GOx through amide bonds. Under the irradiation of a near-infrared laser (808 nm), thermal energy is generated by WS to kill colorectal cancer cells locally. The photothermal conversion efficiency of WS-PVP-LA was 27.2%. This study is anticipated to open up an alternative avenue for the rational design of multifunctional nanotherapeutics for tumor therapy.