Orange-Emissive Sulfur-Doped Organosilica Nanodots for Metal Ion/Glutathione Detection and Normal/Cancer Cell Identification

Abstract

Developing a single nanosensor capable of detecting multiple metal ions or biomolecules remains a challenge. Here, we successfully developed a sensing platform for the efficient detection of various metal ions with orange-emissive sulfur-doped organosilica nanodots (S-OSiNDs). The S-OSiNDs were prepared via a one-pot solvothermal treatment of urea, citric acid, and bis­[3-(triethoxysilyl)­propyl]­tetrasulfide in N,N-dimethylformamide. The as-prepared S-OSiNDs showed a turn-off fluorescence response toward multiple metal ions including Cu2+, Fe3+, [PdCl4]2–, Ag+, Hg2+, and Bi3+, realizing the rapid and sensitive detection with a very low detection limit of 0.6 nM (for Cu2+). In addition, the metal ion-induced fluorescence quenching of S-OSiNDs could be selectively restored by glutathione (GSH), exhibiting a sensitive GSH detection capability with low detection limits ranging from 0.03 to 0.2 μM. On the basis of the metal ion/GSH-triggered on–off–on regulation of the S-OSiNDs’ fluorescence, we successfully realized the detection of Cu2+, Fe3+, [PdCl4]2–, Ag+, Hg2+, and Bi3+ and achieved cancer/normal cell identification via fluorescence microscopic imaging. Overall, the S-OSiNDs may possess great potential for the detection of multiple metal ions in environmental monitoring and clinical diagnosis, and may also serve as a robust platform for cancer cell imaging and identification because of their capacity of highly sensitive sensing of GSH, which is overexpressed in many cancer cells. Furthermore, the present work also demonstrates that S-OSiNDs can be used for the facile synthesis of metal-incorporated nanoparticles, which we believe may find various applications in the future.

Carbon Dots for Intracellular Sensing

“…Until now, different kinds of fluorescent nanomaterials have been developed such as carbon dots (CDs), [1][2][3][4] silicon nanoparticles (NPs), [5][6][7][8][9][10][11][12][13] semiconductor quantum dots (QDs), [14][15][16][17][18] polymer dots, [19][20][21] dye-doped NPs, [19,22] and upconversion NPs. [23,24] Among them, CDs are considered as suitable fluorescent bioprobes due to their properties like good biosafety, facile preparation and modification, fascinating photoluminescence (PL), and excellent aqueous dispersity.…”

Rose Bengal-Derived Ultrabright Sulfur-Doped Carbon Dots for Fast Discrimination between Live and Dead Cells

“…Carbon dots (CDs) are a kind of zero-dimensional photoluminescent carbon nanomaterials with typical sizes less than 10 nm. , Because of their advantages of simple and economical synthesis (e.g., hydrothermal/solvothermal, dry heating/pyrolysis, microwave-assisted, and electrochemical methods), excellent water dispersity, high photostability, good biocompatibility, and easy modification, CDs have been widely applied in biosensing, bioimaging, photocatalysis, and drug delivery. − The doping of different elements in CDs can adjust their band gaps and introduce additional defect sits, which may endow the resultant CDs with the desired electronic/optical properties. A large number of methods have been developed to obtain heteroatom-doped CDs.…”

Platinum‐Coordinated Dual‐Responsive Nanogels for Universal Drug Delivery and Combination Cancer Therapy

“…[19] GSH not only plays a significant role in cancer drug resistance by reacting with drugs directly or participating in the reaction with therapeutics catalyzed by glutathione S-transferase, but also has the ability to scavenge reactive oxygen species (ROS), which may lead to resistance against ROS-based therapies. [19,20] Therefore, some GSH-responsive nanocarriers have been developed for cancer/normal cell differentiation [21][22][23][24] or anticancer drug delivery. [25][26][27][28][29] cis-Diammineplatinum dichloride (also known as cisplatin), a well-known chemotherapeutic drug acting on cancer cell DNA, [30] is able to form a stable product with GSH via Pt−S bond formation.…”