The major challenge in current chemotherapy is to increase local effective therapeutic concentration of drugs as well as to minimize toxicity and side effects for patients. The targeted delivery of drugs to their desired site of action in a controlled manner plays an essential role in the development of drug formulations. A photocage refers to a caged molecule rendered biologically inert by a photolabile protecting group. Molecules are illuminated with light to liberate the caged group and then become active forms. In this study, we formulate upconversion nanoparticles (UCNPs) as the NIR-triggered targeting and drug delivery vehicles that successfully deliver in vitro and in vivo for near-infrared light photocontrolled targeting, bioimaging, and chemotherapy. It is noted that there has been no report on the systemic administration UCNP-based drug delivery agents for evaluation of bioimaging and chemotherapy. To achieve phototargeting, the tumor-homing agent (i.e., folic acid) has been constructed as a photoresponsive molecule. For the chemotherapeutic effect, the antitumor drug doxorubicin is thiolated on the surface of UCNPs, forming a disulfide bond that can be cleaved by lysosomal enzymes within the cells. The caged UNCPs can serve as a platform for the improvement of selective targeting and possible reduction of adverse side effects from chemotherapy.

The best of three worlds: Gold nanorods coated with poly(styrene‐alt‐maleic acid) (see picture; pink), the photosensitizer indocyanine green (black), and antibodies (green “Y”) serve not only as photodynamic therapy and hyperthermia agents to destroy malignant cells, but they also act as optical contrast agents to simultaneously to monitor cells by imaging in the near‐IR region.

Bimetallic nanostructures show exciting potential as materials for effective photothermal hyperthermia therapy. We report the seed-mediated synthesis of palladium-gold (Pd-Au) nanostructures containing multiple gold nanocrystals on highly branched palladium seeds. The nanostructures were synthesized via the addition of a gold precursor to a palladium seed solution in the presence of oleylamine, which acts as both a reducing and a stabilizing agent. The interaction and the electronic coupling between gold nanocrystals and between palladium and gold broadened and red-shifted the localized surface plasmon resonance absorption maximum of the gold nanocrystals into the near-infrared region, to give enhanced suitability for photothermal hyperthermia therapy. Pd-Au heterostructures irradiated with an 808 nm laser light caused destruction of HeLa cancer cells in vitro, as well as complete destruction of tumor xenographs in mouse models in vivo for effective photothermal hyperthermia.

External stimuli responsive dual drugs carrier was synthesized with Au nanorods (NRs) as the platform. On Au NRs, single stranded DNAs were assembled using 5' thiol end. Following this, complementary DNA (cDNA) strands were hybridized. This hybridized double stranded DNA facilitated doxorubicin (Dox) intercalation into the duplexes. The cDNA designed with the 5' amine functional group assisted to tether platinum [Pt(IV)] prodrugs by establishing amide bond with the acid group at the axial ligand. The other axial acid group in Pt(IV) prodrugs was conjugated with the folic acid (FA) to target folate receptors overexpressed in the cancer cells. This targeting vehicle provided remote-controlled delivery of this high toxic cargo cocktail at the tumor site, ensuring extra specificity that can avoid acute toxicity, where release of Dox and Pt(IV) was achieved upon NIR 808 nm diode laser irradiation. The dehybridization set the Dox free to bind the cell nucleus and cellular reductants reduced Pt(IV) to yield toxic Pt(II), becoming an active drug. The in vitro and in vivo studies revealed that this external stimulus responsive combination drug delivery was significantly effective.

Aqueous solution containing two additives, chloroauric acid (HAuCl 4 ) and trisodium citrate (Na 3 C 6 H 5 O 7 ), was irradiated by sunlight, without any additional stimulus such as electric power, to form high-yield Au decahedra. Those Au nanodecahedra were thermodynamically stable and exhibited high performance sensing of lead (Pb 2+ ) ions.Growing global energy consumption leads to continuously increasing accumulation of CO 2 emissions in the atmosphere. Given strong demand for carbon-neutral energy sources, solar energy is widely seen as our largest source of renewable energy. Here, we show a solar-mediated synthesis of high-yield multiplytwinned gold (Au) nanodecahedra. The synthetic process involves only two additives, chloroauric acid (HAuCl 4 ) and trisodium citrate (Na 3 C 6 H 5 O 7 ), without any additional stimulus such as electric power. Importantly, defects to release the buildup of internal stresses in the Au nanodecahedra serve as active sites, resulting in strong coordination with citrate ions donating electrons from the citrate ions to the Au surface. Therefore, without surface modification or any additional preparation, the thermodynamic stable Au nanodecahedra are able to act as label-free Pb 2+ detection sensors. The minimum detectable concentration of Pb 2+ for label-free Au nanodecahedra is 4.8 nM; however, it is much lower (4.8 pM) for glutathionefunctionalized decahedra. We have developed a green, simple, inexpensive, and sensitive colorimetric sensor.Green synthetic strategies are in great demand, as are processes that reduce the variety and amount of products and wastes hazardous to the environment and human health. Choices of chemicals, solvent media, processes and materials all need to be evaluated from a green chemistry perspective. Solar is widely considered to be the largest source of carbonneutral renewable energy. As a chemical reagent, sunlight is non-toxic, non-polluting, and traceless in chemical processes. However, sunlight is only used to a limited extent in the synthesis