Plasma-Functionalized Isotactic Polypropylene Assembledwith Conducting Polymers for Bacterial Quantification byNADH Sensing
Rapid detection of bacterial presence on implantable medical devices isessential to prevent biofilm formation, which consists of densely packedbacteria colonies able to withstand antibiotic-mediated killing. In this work, asmart approach is presented to integrate electrochemical sensors fordetecting bacterial infections in biomedical implants made of isotacticpolypropylene (i-PP) using chemical assembly. The electrochemical detectionis based on the capacity of conducting polymers (CPs) to detect extracellularnicotinamide adenine dinucleotide (NADH) released from cellular respirationof bacteria, which allows distinguishing prokaryotic from eukaryotic cells.Oxygen plasma-functionalized free-standing i-PP, coated with a layer(≈1.1 μm in thickness) of CP nanoparticles obtained by oxidativepolymerization, is used as working electrode for the anodic polymerization ofa second CP layer (≈8.2 μm in thickness), which provides very highelectrochemical activity and stability. The resulting layered material, i-PPf/CP2,detects the electro-oxidation of NADH in physiological media with asensitivity 417 μA cm−2and a detection limit up to 0.14×10−3m, which isbelow the concentration of extracellular NADH found for bacterial cultures ofbiofilm-positive and biofilm-negative strains.
Journal or Serie
Advanced Healthcare Materials, 2021, vol. 10, 2100425