Researchers have developed sensitive nanomaterial biosensors, specifically ZnO/PANI-DBSA and Fe2O3/PANI-DBSA composites, for detecting bacterial signaling molecules like C6-HSL in industrial settings. These sensors offer a cost-effective, efficient method for monitoring biofilm formation and microbial-influenced corrosion in oil and gas fields.
Polycationic polymers necessarily contain counterions to maintain the overall charged balance. Upon treatment of polypyrrole (PPy) films with thiol-terminated poly(ethylene glycol) (PEG), the films undergo efficient surface derivatization that reduces a portion of the film, freeing up some of the "dopant"counterions, while forming a brush-like layer. Quartz crystal microbalance (QCM) measurements show that the PEG brushes resist the adhesion of protein (fetal bovine serum (FBS)) as compared to unmodified PPy. When the dopant is polymeric dextran sulfonate, no change in the QCM resonance frequency is observed. However, when the dopant is dodecylbenzene sulfonic acid (DBSA), exposure of the film to protein causes an increase in the resonance frequency, indicating a loss of mass. X-ray photoelectron spectroscopy (XPS) and liquid chromatography-mass spectroscopy (LCMS) measurements demonstrate that the protein triggers the release of the dopant from the composite. Treatment of DB