A silicon-based PbSe quantum dot near-infrared photodetector with spectral selectivity.

Traditional photodetectors usually respond to photons larger than the bandgap of a photosensitive material. In contrast to traditional photodetectors for broad-spectrum detection, the currently reported PbS/PMMA/PbSe CQD silicon-based photodetectors can detect spectrally selective light sources. This is attributed to two layers with specific functions, a filter layer on top and a photosensitive layer in contact with the silicon channel.

Silicon-based PbS-CQDs infrared photodetector with high sensitivity and fast response.

Silicon-based photodetectors as the main force in visible and near-infrared detection devices have been deeply embedded in modern technology and human society, but due to the characteristics of silicon itself, its response wavelength is generally less than 1100 nm. It is an interesting study to combine the state-of-art silicon processing with emerging infrared-sensitive Lead sulfide colloidal quantum dots (PbS-CQDs) to produce a photodetector that can detect infrared light. Here, we demonstrated a silicon-compatible photodetector that could be integrated on-chip, and also sensitive to infrared light which is owing to a PbS-CQDs absorption layer with tunable bandgap.

Preparation of copolymer paclitaxel covalently linked via a disulfide bond and its application on controlled drug delivery.

A novel controlled drug delivery system based on copolymer covalently linked paclitaxel via a disulfide bond was constructed. Copolymer with poly(ethylene glycol) (PEG) side chains and carboxyl groups on the backbone was prepared by radical copolymerization of tert-butyl acrylate and poly(ethylene glycol) methyl ether acrylate, followed by selectively hydrolyzing tert-butyl groups to carboxyl groups. Utilizing the carboxyl group as an active reaction site, paclitaxel, a well-known chemotherapeutic drug, could be covalently linked to the backbone of a copolymer via a disulfide bond, and the loading content of paclitaxel could reach up to 32 wt %.