Highly Sensitive Bacteria-Responsive Membranes Consisting of Core–Shell Polyurethane Polyvinylpyrrolidone Electrospun Nanofibers for In Situ Detection of Bacterial Infections

Abstract

Bacteria responsive color-changing wound dressings offer a valuable platform for continuous monitoring of the wound bed facilitating early detection of bacterial infections. In this study, we present a highly sensitive electrospun nanofibrous polyurethane wound dressing incorporating a hemicyanine-based chromogenic probe with a labile ester linkage that can be enzymatically cleaved by bacterial lipase released from clinically relevant strains, such as Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA). A rapid chromogenic response was achieved by localizing the dye at the surface of core−shell fibers, resulting in a 5x faster response relative to conventional nanofibers. By incorporating polyvinylpyrrolidone (PVP) dopant in the shell, the sensitivity was boosted to enable detection of bacteria at clinically relevant concentrations after 2 h exposure: 2.5 × 10 5 CFU/ cm 2 P. aeruginosa and 1.0 × 10 6 CFU/cm 2 MRSA. Introduction of PVP in the shell also boosted the degree of hydrolysis of the chromogenic probe by a factor of 1.2× after a 3 h exposure to a low concentration of P. aeruginosa (10 5 CFU/cm 2 ). PVP was also found to improve the discernibility of the color change at high bacterial concentrations. The cooperativity between the chromogenic probe, fiber structure, and polymer composition is well-suited for timely in situ detection of wound infection.

Multifunctional Dressing for Wound Diagnosis and Rehabilitation

“…State-of-the-art wearable sensors and electronics are emerging at an astonishing rate, with recent insights resulting in the rapid development of detection methods (e.g., optical and electrical detection) for paving the way for securely and effectively monitoring different biomarkers in wound exudate (e.g., pH, glucose, and bacteria) and around the wound site (e.g., temperature and shape/size). [53][54][55][56][57][58]…”

Electrospun Nanofibers for Sensing and Biosensing Applications—A Review

“…Core-shell electrospun NFs were used for bacterial infections detection [97]. Various NFs were electrospun, with polyurethane core and different ratios of PU/PVP and PU/polyethylene glycol (PEG) as shell, with hemicyanine based chromogenic probe (HCy, Figure 15) incorporated in the shell of the NFs.…”

Advanced materials for personal thermal and moisture management of health care workers wearing PPE

“…Most recently, electrospinning technique with fascinating characteristics of a wide range of materials, easy incorporation of additives, and remarkably low cost has been established as a simple and scalable method to fabricate BN contained thermally conductive membranes. A variety of BN nanosheets enriched nanofibrous membranes have been fabricated with different polymer templates, including polyvinylidene fluoride (PVDF) [ 219 ], polyvinylpyrrolidone (PVP) [ 220 ], and polyvinyl alcohol (PVA) [ 221 ]. Nevertheless, these membranes must undergo complex subsequent hot pressing to achieve high thermal conductivity, and thus were deprived of porous structure for moisture transportation.…”