Fast Fabrication of Multifunctional PCL/Curcumin Nanofibrous Membranes for Wound Dressings

Abstract

Therapeutic intervention to skin wounds requires covering the affected area with wound dressings. Interdisciplinary efforts have focused on the development of smart bandages that can perform multiple functions. In this direction, here, we designed a low cost (U$0.012 per cm 2 ) multifunctional therapeutic wound dressing fabricated by loading curcumin (CC) into poly(ϵ-caprolactone) (PCL) nanofibers using solution blow spinning (SBS). The freestanding PCL/CC bandages were characterized by distinct physicochemical approaches and were successful in performing varied functions, including controlled release of CC, colorimetric indication of the wound conditions, barrier against microorganisms, being biocompatible, and providing a photosensitive platform for antimicrobial photodynamic therapy (aPDT). The chemical nature of PCL and CC and the interactions between these components allowed CC to be released for 192 h (ca. 8 days), which could be correlated with the Korsmeyer−Peppas model, with a burst release suitable to treat the inflammatory phase. Due to the CC keto−enol tautomerism, an optical indication of the healing status could be obtained using PCL/CC, which occurred immediately, ranging between red/orange and yellow shades. The effect against pathogenic microorganisms evaluated by agar disc-diffusion, affected skin wound simulation (ex vivo), and microbial penetration tests demonstrated the ability to block and inhibit microbial permeation in different environments. The biocompatibilities of PCL and PCL/CC were verified by in vitro cytotoxicity study, which demonstrated that cell viabilities average above 94 and 96% for human dermal fibroblasts. In addition, the proposed bandage responded to aPDT applied to an in vivo assay, showing that, when irritated, PCL/CC was able to reduce the bacteria present on the real wound of mice. In summary, our findings demonstrate that using PCL and CC to produce nonwovens by the SBS technique offers potential for the rapid fabrication of biocompatible and multifunctional wound dressings, paving the way for large-scale production and utilization of such dressings in the treatment of skin wounds.

Synergistic Tetracycline–Curcumin Association in Biocompatible PCL Nanostructured Wound Dressings

“…aureus ,, has been reported, the mats containing only CC did not show a visible inhibition halo. Physical properties such as solubility or diffusion capacity of an antimicrobial compound can hinder its diffusion on the agar medium, making a direct comparison using the agar diffusion method inappropriately. , On the other hand, all samples containing TC showed inhibition zones for S. aureus and E.…”

“…Thus, all samples show the macroscopic mechanical characteristics of easy and resistant handling, required for wound dressing application . Moreover, the wound dressing’s mechanical resistances for handling and its flexibilities are demonstrated in Figure B, corroborating our previous work …”

“…These observations suggest that this compound interferes in PCL crystallization and, as also indicated by the X c values, these interactions did not induce PCL crystallinity. These results indicate that CC can prevent PCL interchain interactions and then impair its crystallization. , Similar effects are observed for samples loaded with TC, but at lower intensities, as corroborated by a mild shift of the melting peak and Δ H m values.…”

“…The ability of the wound dressings to hinder the environment microbial contact with the injured skin was evaluated according to the microbial penetration test, described in detail elsewhere. ,, Specimens of 3 × 3 cm were used to seal test tubes filled with 15 mL of MHB. Negative controls (C−), referring to tubes sealed with parafilm, helped in the evaluation of asepsis of the growth medium as well as the color variations of MHB free of microorganisms.…”

“…As revealed in our previous study, PCL NFs produced by SBS hold significant potential for the rapid production of large nanostructured wound dressings, within a manufacturing time frame of less than 1 h, and at a low cost ($0.012 per cm 2 ). This study takes a step further by engineering nanostructured wound dressings using PCL through the SBS technique, which contains a reduced dosage of the conventional antibiotic tetracycline (TC) synergistically combined with the natural compound curcumin (CC).…”