Polymeric carrier-mediated intracellular delivery of phosphatidylinositol-3,4,5-trisphosphate to overcome insulin resistance.

Background: Phosphatidylinositol-3,4,5-trisphosphate (PIP3) is a major lipid second messenger in insulin-mediated signalling towards the metabolic actions of this hormone in muscle and fat.

Purpose: Assessing the intracellular transport of exogenous PIP3 attached to a polymeric carrier in an attempt to overcome cellular insulin resistance.

Methods: Artificial chromatic bio-mimetic membrane vesicles composed of dimyristoylphosphatidylcholine and polydiacetylene were applied to screen the polymeric carriers.

Biomimetic approaches for studying membrane processes.

This short review focuses on recent innovative systems and experimental approaches designed to investigate membrane processes and biomolecular interactions associated with membranes. Our emphasis is on "biomimetics" which reflects the significance and contributions of the chemistry/biology interface in addressing complex biological questions. We have not limited this review to discussion of new "sensors" or "assays"per se, but rather we tried to review new concepts employed for analysis of membrane processes.

Colorimetric detection and fingerprinting of bacteria by glass-supported lipid/polydiacetylene films.

Glass-supported films of lipids and polydiacetylene were applied for visual detection and colorimetric fingerprinting of bacteria. The sensor films comprise polydiacetylene domains serving as the chromatic reporter interspersed within lipid monolayers that function as a biomimetic membrane platform. The detection schemes are based on either visible blue-red transitions or fluorescence transformations of polydiacetylene, induced by amphiphilic molecules secreted by proliferating bacteria.

Rapid chromatic detection of bacteria by use of a new biomimetic polymer sensor.

We present a new platform for visual and spectroscopic detection of bacteria. The detection scheme is based on the interaction of membrane-active compounds secreted by bacteria with agar-embedded nanoparticles comprising phospholipids and the chromatic polymer polydiacetylene (PDA). We demonstrate that PDA undergoes dramatic visible blue-to-red transformations together with an intense fluorescence emission that are induced by molecules released by multiplying bacteria.