Bridging Flocculation of a Sterically Stabilized Cationic Latex as a Biosensor for the Detection of Microbial DNA after Amplification via PCR.

There is a high demand for rapid, sensitive, and accurate detection methods for pathogens. This paper demonstrates a method of detecting the presence of amplified DNA from a range of pathogens associated with serious infections including Gram-negative bacteria, Gram-positive bacteria, and viruses. DNA is amplified using a polymerase chain reaction (PCR) and consequently detected using a sterically stabilized, cationic polymer latex.

Visible label-free detection of bacterial DNA using flocculation of sterically stabilised cationic latexes.

The current gold standard diagnostic for bacterial infections is the use of culture, which can be time consuming and can take up to five days for results to be reported. There is therefore an unmet clinical need for a rapid and label free alternative. This paper demonstrates a method of detecting the presence of amplified DNA from bacterial samples using a sterically-stabilised, cationic polymer latex and widely available equipment, providing an accessible alternative DNA detection technique.

Physical Adsorption of Graphene Oxide onto Polymer Latexes and Characterization of the Resulting Nanocomposite Particles.

Polymer/graphene oxide (GO) nanocomposite particles were prepared heteroflocculation between 140-220 nm cationic latex nanoparticles and anionic GO nanosheets in either acidic or basic conditions. It is demonstrated that nanocomposite particles can be formed using either poly(2-vinylpyridine)--poly(benzyl methacrylate) (P2VP-PBzMA) block copolymer nanoparticles prepared by reversible-addition chain-transfer (RAFT)-mediated polymerization-induced self-assembly (PISA), or poly(ethylene glycol)methacrylate (PEGMA)-stabilized P2VP latexes prepared by traditional emulsion polymerization. These two latexes are different morphologically as the P2VP-PBzMA block copolymer latexes have P2VP steric stabilizer chains in their corona, whereas the PEGMA-stabilized P2VP particles have a P2VP core and a nonionic steric stabilizer.