Synthesis of Poly(ε-caprolactone) Diacrylate for Micelle-Cross-Linked Sodium AMPS Hydrogel for Use as Controlled Drug Delivery Wound Dressing

Abstract

This study focuses on the synthesis of poly­(ε-caprolactone) diacrylate (PCLDA) for the fabrication of micelle-cross-linked sodium AMPS wound dressing hydrogels. The novel synthetic approach of PCLDA is functionalizing a PCL diol with acrylic acid. The influences of varying the PCL diol/AA molar ratio and temperature on the suitable conditions for the synthesis of PCLDA are discussed. The hydrogel was synthesized through micellar copolymerization of sodium 2-acrylamido-2-methylpropane sulfonate (Na-AMPS) as a basic monomer and PCLDA as a hydrophobic association monomer. In this study, an attempt was made to develop new hydrogel wound dressings meant for the release of antibacterial drugs (ciprofloxacin and silver sulfadiazine). The chemical structures, morphology, porosity, and water interaction of the hydrogels were characterized. The hydrogels’ swelling ratio and water vapor transmission rate (WVTR) showed a high swelling capacity (4688–10753%) and good WVTR (approximately 2000 g·m–2·day–1), which can be controlled through variation of the PCLDA concentration. The mechanical property results confirmed that PCLDA improved the mechanical properties of the hydrogel; the stress increased from 37 to 68 kPa, and the strain increased from 198 to 360% with increasing PCLDA (0–30% wt of Na-AMPS). These hydrogels presented no cytotoxicity based on over 70% cell viability responses (L929 fibroblasts) using an in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Additionally, the drug release mechanism, kinetic models, and antibacterial activity were determined. The results demonstrated that antibiotics were released from the hydrogel with a Fickian diffusion mechanism and antibacterial activity against Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive bacteria (Staphylococcus aureus). Based on the results obtained, and bearing in mind that further progress still needs to be made, the fabricated hydrogels show considerable potential for meeting the stringent property requirements of hydrogel wound dressings.

Injectable Self-Healing Adhesive Chitosan Hydrogel with Antioxidative, Antibacterial, and Hemostatic Activities for Rapid Hemostasis and Skin Wound Healing

“…Cell proliferation was detected by CCK-8 assay, and the untreated group was set as the control group. Results are shown in Figure C; after being cultured with the hydrogel extract for 1 and 2 days, the activity of L929 cells in all hydrogel groups was above 70%, which is in compliance with international biomaterial standards (ISO10993:2009) . In addition, the bright green fluorescence specific labeling live cell was observed in all hydrogel groups, indicating that these QCS/TA hydrogels were cyto-compatible in vitro (Figure D).…”

“…Results are shown in Figure 8C; after being cultured with the hydrogel extract for 1 and 2 days, the activity of L929 cells in all hydrogel groups was above 70%, which is in compliance with international biomaterial standards (ISO10993:2009). 62 In addition, the bright green fluorescence specific labeling live cell was observed in all hydrogel groups, indicating that these QCS/TA hydrogels were cyto-compatible in vitro (Figure 8D). The superior performance of the QCS/TA 2.5 hydrogel encouraged us to assess its biocompatibility in vivo.…”

Release kinetics and binding interactions of curcumin‐encapsulated nanoparticles released from chitosan‐graft‐(methoxy poly(ethylene glycol)‐block‐polycaprolactone) injectable hydrogels

“…The Korsmeyer‐Peppas model, based on the exponent of the power law ( M t / M ∞ = kt n ), gave information regarding the release mechanism of the encapsulated drug from the matrix based on the value of n . For the case of a cylindrical matrix, n < 0.5 corresponds to pseudo‐Fickian diffusion, n = 0.5 is Fickian diffusion, 0.5 < n < 1.00 defines anomalous (non‐Fickian) transport and n = 1.00 signifies zero‐order release 19,22 . Thus, the release of curcumin‐loaded hydrogels at concentrations of 800, 1400, 1900 and 2200 μg mL −1 was characterized as non‐Fickian transport, which indicated that drug release is controlled by more than one process, i.e.…”

“…The preparations of the prodrugs, however, are relatively complex and involve various steps; thus, direct loading is preferably employed because of its simple preparation method. To establish effective drug delivery materials, mathematical models have been applied to define and predict the comprehension of all the phenomena involving release kinetics, such as diffusion through the polymeric matrices, desorption of drug bound to the surface, polymer matrix erosion, a combined erosion‐diffusion process etc 18,19 . The carriers must be sufficiently stable to prohibit burst or rapid delivery but biologically degradable over an appropriate duration to allow controllable release and prolong the circulation time of the drug.…”

“…To establish effective drug delivery materials, mathematical models have been applied to define and predict the comprehension of all the phenomena involving release kinetics, such as diffusion through the polymeric matrices, desorption of drug bound to the surface, polymer matrix erosion, a combined erosion-diffusion process etc. 18,19 The carriers must be sufficiently stable to prohibit burst or rapid delivery but biologically degradable over an appropriate duration to allow controllable release and prolong the circulation time of the drug. Also, the amount of released drug should enable the attainment of the desired drug concentrations.…”