A supramolecular antibiotic switch is described that can reversibly "turn-on" and "turn-off" its antibacterial activity on demand, providing a proof-of-concept for a way to regulate antibacterial activity of biotics. The switch relies on supramolecular assembly and disassembly of cationic poly(phenylene vinylene) derivative (PPV) with cucurbit[7]uril (CB[7]) to regulate their different interactions with bacteria. This simple but efficient strategy does not require any chemical modification on the active sites of the antibacterial agent, and could also regulate the antibacterial activity of classical antibiotics or photosensitizers in photodynamic therapy. This supramolecular antibiotic switch may be a successful strategy to fight bacterial infections and decrease the emergence of bacterial resistance to antibiotics from a long-term point of view.

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.

Using cell-surface modification and biotin-streptavidin interactions, immune cells and target tumor cells are made to form multicellular assemblies. A polythiophene derivative can undergo cellular uptake, allowing the sensitization of oxygen under light irradiation. The subsequent generation of reactive oxygen species (ROS) regulates cell-cell communication in time and space.

This paper describes an associated analysis method of DNA methylation for the detection of cancer using an optically amplifying cationic conjugated polymer (CCP, poly{(1,4-phenylene)-2,7-[9,9-bis(6'-N,N,N-trimethyl ammonium)-hexyl fluorene] dibromide)}. Genomic DNA is digested by methylation-sensitive restriction endonuclease, followed by PCR amplification to incorporate fluorescein-labeled dNTP. Only methylated DNA can be amplified by PCR, and the methylation level is detected through fluorescence resonance energy transfer (FRET) between CCP and fluorescein that is incorporated into the PCR product. The methylation levels of RASSF1A, OPCML, and HOXA9 promoters of 35 ovarian cancer samples and 11 normal samples were assayed. In accordance with the degree of methylation levels, they are clustered to three sections and assigned a value. Through an associated analysis, we acquired a threshold for cancer detection with a sensitivity of 85.7%. The assay takes about 20 h to obtain the detection results and shows great potential as a useful tool for diagnostic and screening of cancer.

A series of cationic conjugated oligoelectrolytes (COEs) was designed to understand how variations in molecular dimensions impact the relative activity against bacteria and mammalian cells.

An unconventional strategy that can be temporally and remotely activated with light to combat the drug resistance of cancer cells is developed. A cell-membrane-anchored photosensitizer (OPV) is used to enhance anticancer drug uptake and restore toxicity in resistant cancer cells. This method recovers the activity of the already established anticancer drugs, and provides a new strategy for the development of light manipulation to combat anticancer resistance.

Asupramolecular antibiotic switchisdescribed that can reversibly "turn-on" and "turn-off"i ts antibacterial activity on demand, providing ap roof-of-concept for aw ay to regulate antibacterial activity of biotics.The switchrelies on supramolecular assembly and disassembly of cationic poly(-phenylene vinylene) derivative (PPV) with cucurbit [7]uril (CB [7]) to regulate their different interactions with bacteria. This simple but efficient strategy does not require any chemical modification on the active sites of the antibacterial agent, and could also regulate the antibacterial activity of classical antibiotics or photosensitizers in photodynamic therapy. This supramolecular antibiotic switchm ay be as uccessful strategy to fight bacterial infections and decrease the emergence of bacterial resistance to antibiotics from al ong-term point of view.

A new water-soluble conjugated poly(fluorene-co-phenylene) derivative (PFP-FB) modified with boronate-protected fluorescein (peroxyfluor-1) via PEG linker has been designed and synthesized. In the presence of H2O2, the peroxyfluor-1 group can transform into green fluorescent fluorescein by deprotecting the boronate protecting groups. In this case, upon selective excitation of PFP-FB backbone at 380 nm, efficient fluorescence resonance energy transfer (FRET) from PFP-FB backbone to fluorescein occurs, and accordingly, the fluorescence color of PFP-FB changes from blue to green. Furthermore, the emission color of PFP-FB and the FRET ratio change in a concentration-dependent manner. By taking advantage of PFP-FB, ratiometric detection of choline and acetylcholine (ACh) through cascade enzymatic reactions and further dynamic monitoring of the choline consumption process of cancer cells have been successfully realized. Thus, this new polymer probe promotes the development of enzymatic biosensors and provides a simpler and more effective way for detecting the chemical transmitter of living cells.