Abstract: The invention provides a method for detecting bacteria. The method utilises a peptide that forms a complex with a conjugated reporter polymer and is susceptible to cleavage by one or more proteases on the surface of a bacteria. Presence or absence of the bacteria can be determined by assessing the optical absorption and/or colour and/or photoluminescence (e.g. fluorescence) of the conjugated reporter polymer, which may undergo a conformational change after binding with the to the cleaved peptide substrate. Specifically, the peptide substrate may comprise a cleavage site for digestion by the protease, and the protease may be an omptin protease. The conjugated reporter polymer may be selected from a polythiophene, a poly(1,4-phenylene vinylene) (PPV), a poly(1,4-phenylene) (PPP), a polyfluorenes (PFO), a nitrogen-containing polymer such as polyquinoline, poly(2,5-pyridinevinylene) (PPyV), 1,3,4-oxadiazole, and poly(9-vinylcarbazole) (PVK), and a polypyrrole.

Abstract: The present invention provides branched amphipathic peptides and vesicles formed thereof. The peptides comprise a polar/positively charged C-terminal segment, a branch point, and two hydrophobic N-terminal segments extending from the branch point. The vesicles are formed using a plurality of first and second peptides, wherein the first peptide has a different chain length from the second peptide. When a plurality of the first and second peptides are mixed together, they self-assemble to form small spheres defined by a membrane consisting of an interlocking peptide network bilayer and having a liquid-receiving interior space (i.e., hollow core). In the bi-layer, the respective hydrophobic segments of the peptides form beta-sheet structures having a hydrogen bond-stabilized, anti-parallel orientation in which the opposed sequences interlock to form a zipper-like structure in three dimensions. Thus, the peptide assembly (i.e.

Abstract: The present invention provides branched amphipathic peptides and vesicles formed thereof. The peptides comprise a polar/positively charged C-terminal segment, a branch point, and two hydrophobic N -terminal segments extending from the branch point. The vesicles are formed using a plurality of first and second peptides, wherein the first peptide has a different chain length from the second peptide. When a plurality of the first and second peptides are mixed together, they self-assemble to form small spheres defined by a membrane consisting of an interlocking peptide network bilayer and having a liquid-receiving interior space (i.e., hollow core). In the bi-layer, the respective hydrophobic segments of the peptides form beta-sheet structures having a hydrogen bond-stabilized, anti-parallel orientation in which the opposed sequences interlock to form a zipper-like structure in three dimensions. Thus, the peptide assembly (i.e.