Lysosome-controlled efficient ROS overproduction against cancer cells with a high pH-responsive catalytic nanosystem

Abstract

Excess reactive oxygen species (ROS) have been proved to damage cancer cells efficiently. ROS overproduction is thus greatly desirable for cancer therapy. To date, ROS production is generally uncontrollable and outside cells, which always bring severe side-effects in the vasculature. Since most ROS share a very short half-life and primarily react close to their site of formation, it would be more efficient if excess ROS are controllably produced inside cancer cells. Herein, we report an efficient lysosome-controlled ROS overproduction via a pH-responsive catalytic nanosystem (FeOx-MSNs), which catalyze the decomposition of H2O2 to produce considerable ROS selectively inside the acidic lysosomes (pH 5.0) of cancer cells. After a further incorporation of ROS-sensitive TMB into the nanosystem (FeOx-MSNs-TMB), both a distinct cell labeling and an efficient death of breast carcinoma cells are obtained. This lysosome-controlled efficient ROS overproduction suggests promising applications in cancer treatments.

Efficient Active Oxygen Free Radical Generated in Tumor Cell by Loading-(HCONH2)·H2O2 Delivery Nanosystem with Soft-X-ray Radiotherapy

“…Oxidatively sensitive non-fluorescence probe DCFH-DA was utilized to measure the intracellular ROS level. DCFH-DA can be deacetylated by nonspecific esterase to form DCFH, which was further oxidized by intracellular ROS to produce a stable fluorescent ROS-sensitive compound 2 ′, 7 ′-dichlorofluorescein (DCF) [ 36 ]. In this study, 4T1 cells were seeded into petri dishes at a density of 5.0 × 10 4 cells and cultured with serum-free media containing FPO@HMSNs-PAA (16 and 32 μg·mL −1 ).…”

Tailoring Enzyme‐Like Activities of Gold Nanoclusters by Polymeric Tertiary Amines for Protecting Neurons Against Oxidative Stress

“…These results confirmed that the pretreatment of primary neuron cells with AuNCs‐NH 2 exhibited excellent protection from the H 2 O 2 ‐induced toxicity. It should be noted that IONPs and Ac‐G 9 PtNPs have been reported to enhance H 2 O 2 ‐induced cell damage dramatically due to their intrinsic peroxidase‐like activity under H 2 O 2 challenge . In contrast, neurons treated with AuNCs‐NH 2 did not enhance cell death after H 2 O 2 challenge, supporting that the peroxidase‐like activity of AuNCs‐NH 2 was negligibly weak intracellularly.…”

Luminescent mesoporous nanorods as photocatalytic enzyme-like peroxidase surrogates

“…The fluorescence intensity of this derivative correlates with the level of ˙OH radical formation. 68 The preparation of NaTA was carried out by neutralization of 0.8 g of TA with 50 mL of aqueous 0.05 N NaOH solution with constant stirring for 1 h. Then, 8.3 g of NaOH were added to reach 14% by weight concentration and favor the precipitation of the desired product. Under these conditions, the precipitate NaTA was filtered and dried in an oven at 110 °C for 12 hours.…”