Comparative Study of Poly (ε-Caprolactone) and Poly(Lactic-co-Glycolic Acid) -Based Nanofiber Scaffolds for pH-Sensing

Abstract

Purpose This study aims to develop biodegradable and biocompatible polymer-based nanofibers that continuously monitor pH within microenvironments of cultured cells in real-time. In the future, these fibers will provide a scaffold for tissue growth while simultaneously monitoring the extracellular environment. Methods Sensors to monitor pH were created by directly electrospinning the sensor components within a polymeric matrix. Specifically, the entire fiber structure is composed of the optical equivalent of an electrode, a pH-sensitve fluorophore, an ionic additive, plasticizer, and a polymer to impart mechanical stability. The resulting poly(ε-caprolactone) (PCL) and poly(lactic-co-glycolic acid) (PLGA) based sensors were characterized by morphology, dynamic range, reversibility and stability. Since PCL-based nanofibers delivered the most desirable analytical response, this matrix was used for cellular studies. Results Electrospun nanofiber scaffolds (NFSs) were created directly out of optode material. The resulting NFS sensors respond to pH changes with a dynamic range centered at 7.8 ± 0.1 and 9.6 ± 0.2, for PCL and PLGA respectively. NFSs exhibited multiple cycles of reversibility with a lifetime of at least 15 days with preservation of response characteristics. By comparing the two NFSs, we found PCL-NFSs are more suitable for pH sensing due to their dynamic range and superior reversibility. Conclusion The proposed sensing platform successfully exhibits a response to pH and compatibility with cultured cells. NSFs will be a useful tool for creating 3D cellular scaffolds that can monitor the cellular environment with applications in fields such as drug discovery and tissue engineering.

Electrospinning and Electrospun Nanofibers: Methods, Materials, and Applications

“…Such pH-responsive nanofibers have been explored for pH-triggered drug release 549,551 and are also promising as a pH sensor to monitor the pH value of a medium. 552 For example, luminescent pH-responsive nanofibers were used for continuously monitoring the pH of a culture medium to minimize the risk of contamination, providing a simple and sensitive platform superior to the conventional pH electrode. 553…”

Biomedical Applications and Research Progress of Electrospinning Technology and Electrospinning Nanofibers

“…In recent years, some scientists have prepared a series of responsive micro/nanofibers, such as temperature-sensitive micro/nanofibers [82,83,84], pH-sensitive micro/nanofibers [78,79,80], magnetic micro/nanofibers [128,129], conductive micro/nanofibers [130,131]. How to combine electrospinning with computer chip technology, It will be better way to accurately regulate and timely control the programmable and controllable degradation in vivo.…”

Nanocontrollers for In Vitro Drug Release Based on Core‐Sheath Encapsulation of Theophylline into Hydroxypropyl Methylcellulose Acetate Succinate Nanofibers

“…Thus, sustained release can be realized at the same time. Other researchers have paid attention to preparing pH stimulus‐responsive drug vehicles with nanostructures such as nanocomposites, 22 nanovalves, 23 nanoparticles, 13,24 nanogels, 1 nanofibers 25 and so on. In these structures, nanofibers have shown more prominent performances because of their greater specific area and very high length‐to‐diameter ratio 26,27 .…”