Except for chemotherapy, surgery, and radiotherapy, photodynamic therapy (PDT) as new therapy modality is already in wide clinic use for the treatment of various diseases. The major bottleneck of this technique is the requirement of outer light source, which always limits effective application of PDT to the lesions in deeper tissue. Here, we first report a new modality for treating cancer and microbial infections, which is activated by chemical molecules instead of outer light irradiation. In this system, in situ bioluminescence of luminol can be absorbed by a cationic oligo(p-phenylene vinylene) (OPV) that acts as the photosensitizer through bioluminescence resonance energy transfer (BRET) process. The excited OPV sensitizes oxygen molecule in the surroundings to produce reactive oxygen species (ROS) that kill the adjacent cancer cells in vitro and in vivo, and pathogenic microbes. By avoiding the use of light irradiation, this work opens a new therapy modality to tumor and pathogen infections.

A new water-soluble conjugated polymer containing fluorene and boron-dipyrromethene repeat units in the backbones (PBF) that exhibits red emission was synthesized and characterized. Cationic PBF forms uniform nanoparticles with negatively charged disodium salt 3,3'-dithiodipropionic acid (SDPA) in aqueous solution through electrostatic interactions. The nanoparticles display absorption maximum at 550 nm and emission maximum at 590 nm. Upon photoexcitation with white light (400-800 nm) with 90 and 45 mW·cm(-2) for bacteria and cancer cells killing respectively, PBF nanoparticles can sensitize the oxygen molecule to readily produce reactive oxygen species (ROS) for rapidly killing neighboring bacteria and cancer cells. Furthermore, PBF nanoparticles concurrently provide optical imaging capability. PBF nanoparticles are therefore a promising multifunctional material for treating cancers and bacteria infections, while concurrently providing optical monitoring capabilities.

Alterations in the methylation of promoters of cancer-related genes are promising biomarkers for the early detection of disease. Compared with single methylation alteration, assessing combined methylation alterations can provide higher association with specific cancer. Here we use cationic conjugated polymer-based fluorescence resonance energy transfer to quantitatively analyse DNA methylation levels of seven colon cancer-related genes in a Chinese population. Through a stepwise discriminant analysis and cumulative detection of methylation alterations, we acquire high accuracy and sensitivity for colon cancer detection (86.3 and 86.7%) and for differential diagnosis (97.5 and 94%). Moreover, we identify a correlation between the CpG island methylator phenotype and clinically important parameters in patients with colon cancer. The cumulative analysis of promoter methylation alterations by the cationic conjugated polymer-based fluorescence resonance energy transfer may be useful for the screening and differential diagnosis of patients with colon cancer, and for performing clinical correlation analyses.

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Nowadays, microorganisms, including bacteria and viruses, are regarded as new environmental pollutants and pose serious threats to public health. Yet, traditional disinfection approaches for bacteria and viruses are generally ineffective. Furthermore, they exhibit the disadvantages of high-energy consumption, environmental pollution, high cost, and toxic byproduct generation. In this respect, nanomaterials display promising antimicrobial capabilities due to their unique properties and provide solutions to the abovementioned issues. Herein, recent progress in the development of 2D nanomaterials displaying antimicrobial capabilities is highlighted. The structures, morphologies, and performances of essential metal, graphene, and nitride-based 2D antibacterial nanomaterials are summarized in detail. In addition, possible antimicrobial mechanisms and the relationship between structure and antimicrobial efficiency are elaborated.

Sulfonated hyperbranched polymers were recently reported to efficiently mimic cellulase activity, producing large quantities of glucose from cellulose.

Resin-based dental materials have raised debates concerning their safety and biocompatibility, resulting in a growing necessity of profound knowledge on the quantity of released compounds into the oral cavity. In this context, the aim of this study was to develop a comprehensive and reliable procedure based on liquid chromatography with mass spectrometry for the simultaneous analysis of various leached compounds (including bisphenol A based compounds) in samples from in vitro experiments. Different experiments were performed to determine the optimal analytical parameters, comprising mass spectrometry parameters, chromatographic separation conditions, and sample preparation. Four internal standards were used as follows: deuterated diethyl phthalate and bisphenol A (commercially available), and deuterated analogues of triethylene glycol dimethacrylate and urethane dimethacrylate (custom-made). The optimized method was validated for linearity of the calibration curves and the associated correlation coefficient, lower limit of quantification, higher limit of quantification, and intra- and interassay accuracy and precision. Additionally, the developed liquid chromatography with tandem mass spectrometry method was applied to the analysis of leaching compounds from four resin-based dental materials. The results indicated that this method is suitable for the analysis of different target compounds leaching from dental materials. This method might serve as a valuable basis for quick and accurate quantification of leached compounds from resin-based dental materials in biological samples.

A novel palladium-catalyzed direct C(sp )-H arylation of the methyl group at the 8-position of BODIPY by bromoarenes was established. A deprotonative cross-coupling process was supposed to be involved in the reaction. This approach allowed us to attach electron-donating/withdrawing, halogen substituted aryls and a heteroaryl with a yield running from 55 to 99 %. Novel pH sensors, which in the absence of acid showed the occurrence of photoinduced electron transfer, were synthesized by attaching dimethylaniline to the methyl at the C8-position of BODIPY. The reference compounds with dimethylaniline directly attached to the C8-position were also synthesized and besides photoinduced electron transfer also showed a charge-transfer emission. Their photophysical properties were investigated by steady-state fluorescence, time-correlated single-photon counting and femtosecond fluorescence up-conversion. Time-dependent density functional (TD-DFT) electronic-structure calculations on the properties of the excited states corresponding to local excitation of the BODIPY core and to charge transfer were conducted. Upon addition of trifluoroacetic acid in toluene and ethanol, the partial fluorescence intensity recovery was at least an order of magnitude more efficient with the newly synthesized sensors compared to the traditional reference sensors. The improved sensitivity of these novel BODIPY-based pH sensors was attributed to less efficient proton-coupled electron transfer of the protonated species.