Functionalization of electrospun poly(caprolactone) fibers for pH-controlled delivery of doxorubicin hydrochloride

Abstract

Functionalized electrospun polymer fibers are a promising candidate for controlled delivery of chemotherapeutic drugs to improve the therapeutic efficacy and to reduce the potential toxic effects by delivering the drug at a rate governed by the physiological need of the site of action. In this study, poly(caprolactone) (PCL) fibers were fabricated by electrospinning, followed by hydrolyzation to introduce functional groups on the fiber surface. Characterization studies were performed on these functionalized fibers using X-ray photoelectron spectroscopy, scanning electron microscopy, and Toluidine Blue O dye assay. The pH-sensitivity of the functional groups on the fiber surface and doxorubicin hydrochloride was utilized to bind the drug electrostatically to these functionalized PCL fibers. The effect of pH on drug loading and release kinetics was investigated. Results indicate successful electrostatic binding of the drug to functionalized electrospun fibers and a high drug payload. The drug delivery response can be modulated by introduction of suitable stimuli (pH).

pH-responsive drug release from functionalized electrospun poly(caprolactone) scaffolds under simulatedin vivoenvironment

“…This could be due to more DOX being released from scaffolds subjected to an acidic media of pH 6.0 as compared to normal tissue pH 7.2. [22] The residual DOX content analysis done on the scaffolds shows that approximately 59% DOX was released from scaffolds subjected to pH 7.2 and approximately 68% was released from scaffolds subjected to pH 6.0. This roughly corresponds to 14 μM DOX concentration to which cells were subjected to at pH 7.2 and 17 μM DOX concentration for cells at pH 6.0.…”

“…[20] The amenability of zebrafish to pharmacological testing and superior imaging properties of fish tissues that allow visualization of cancer progression and angiogenesis in live animals makes it an attractive animal model choice for cancer research. [21] In our previous publication, [22] we have shown that hydrolysis of electrospun PCL scaffolds leads to the generation of functional groups (-COOH) on the fiber surface that can be utilized to ionically bind DOX at a certain pH (~ 17,000 ng/mg drug payload). The change in pH would result in disruption of ionic bonds between the two and the drug would be released from these scaffolds at an acidic pH.…”

Multifunctional Electrospun Nanofibers for Enhancing Localized Cancer Treatment

“…Surface modification of drug delivery systems has been a common strategy for enabling controlled drug delivery at the targeted site . A number of research using individual or a combination of surface modifications has been carried out on electrospun fibers to control the release of immobilized anticancer drugs whilst preserving functionality.…”

Various Techniques to Functionalize Nanofibers

“…Liu et al fabricated electrospun fibers containing amine functional surface using polyurethane, 3-aminopropyltriethoxysilane, and utilized the charged functional groups (pH 3-5) -NH 3 + and -COO À for the adsorption of silver nanoparticles through electrostatic interaction [83]. Jassal et al fabricated PCL electrospun fibers, immobilized doxorubicin on hydrolyzed PCL fibers, and proved that doxorubicin drug adsorption on electrospun fibers is strongly pH dependent [84]. Various parameters such as surface charge, topography, roughness pH, and ionic strength of the ESM environment control the adsorption of drugs and nanoparticles.…”