Patent Application
20230181371
The present invention relates to the preparation of polyacrylonitrile nanofibers incorporated Zinc Oxide-Quercetin nanoparticles wound dressing material with antibacterial and wound healing potentials.
Chronic wounds are medical care concern and severe clinical challenge worldwide. Chronic wounds affected patients are burns victims or may be caused by skin ulcers due to venous stasis, pressure or diabetes mellitus. Diabetic foot ulcers or wounds are prevalent in patient suffering from diabetes mellitus. Wound healing failures observed in diabetic patients are caused by multiple factors including neuropathy, re-current inflammation due to high blood sugar levels that eventually leads to amputation. Conventional wound dressings like gauzes, bandages and superabsorbent cotton limits to the basic protection and do not achieve the requirement of wound care and aesthetic of the natural skin. However, multifunctional wound patches are designed to cure the skin functionalities. To accelerate the regeneration of wound tissues, dressing with swelling capacity to absorb the exudate, stretchable, enhance angiogenesis, maintains asepsis, and biocompatible nature are desired. They ensures the suitable biological environment and efficient delivery of drug to eliminate the infections without any adverse effect. Recently, non-woven electro-spun fibers have proven as excellent materials to fasten the healing process and prevent bacterial infections.
Nanofibers fabricated through electrospinning technique possess high porosity, high surface to volume ratio and creates a biomimetic system that serves as extra-cellular matrix (ECM). These characteristics of nanofibers provide suitable wound dressing scaffold that promotes skin regeneration, retains moisture, hemostasis, and cell respiration. Moreover, electrospun nanofibrous dressings are promising matrix for patient compliance as the need of frequently changing bandages is reduced. Incorporation of antimicrobial or therapeutic agents to functionalized nanofiber materials serve as potential bandages to relieve pain and promote healing that will contour to virtually any wound surface.
To fabricate nanofibrous material, polyacrylonitrile (PAN) is employed due to its biocompatibility along with excellent mechanical and thermal strength, non-toxicity, commercial availability and better spinnability. PAN nanofibers have controlled diameter ranging from 100-300 nm. In addition, zinc oxide nanoparticles owing to its antimicrobial, fibroblast proliferation and angiogenesis properties, is incorporated into PAN polymeric nanofibrous mat as an active ingredient for the wound patches.
Quercetin is a flavonoid and pharmacological active agent that delays oxidative stress and prevent cell death. It is incorporated into nanofibrous scaffold to promote the wound healing, as it possesses high antibacterial and antioxidant properties. Therefore, considering the aforementioned factors, biocompatible polymer incorporated with metal oxide nanoparticle along with nutraceutical (Quercetin) by electrospinning are invented that are suitable for the biological environment of wound to mediates healing and reduce pain.
The present embodiment relates to the synthesis of nanofibers comprising of polyacrylonitrile, metal oxide nanoparticles loaded with nutraceuticals and its application for wound healing. The nanofibrous scaffold designed herein are loaded with Quercetin as the potential candidates. Moreover, zinc oxide has been incorporated due to the angiogenetic and anti-microbial potential. The nanofibers in the embodiment are referred to as PAN/ZnO/Quercetin (PAN/ZnO/Que). The nanofibers mat may have a diameter of 160 nm. Nanofibers in accordance with the embodiment were formed through electrospinning technique. The voltage of electrospinning was kept in the range of 10-15kV. The non-woven matrix has been designed for use as a wound dressing to cure diabetic wounds. The scaffold herein has the multifunctional properties such as biocompatibility, antimicrobial, angiogenic and drug delivery potential at the site of action. Thus, the developed dressing has the capability to cure wounds, applied over the wound to accelerate the healing, and improves the patient compliance.
The current invention described herein is related to the synthesis of polyacrylonitrile based nanofibers loaded with ZnO Quercetin nanoparticles (PAN/ZnO-Que nanofibers) and their application as a biological wound dressing. PAN/ZnO-Que nanofibers according to the embodiment disclosure provides several benefits over the conventional wound patches including: biocompatibility, low cost, durability, better mechanical properties, angiogenic nature, anti-microbial potential and drug release at the target site. The polymer used in this invention is biocompatible and cheap which is impregnated with ZnO and Quercetin to enhance its additive properties in nano range. In the embodiment, the nanofibers have been produced using electrospinning.
Electrospinning is a technique to develop electrostatic fiber from electrospinnable polymer ranging from 10 nm to 1000 nm in diameter. The electrospinning instrument includes typically high voltage supply. The nanomaterial engineered through electrospinning facilitates a higher surface area to volume ratio, which mimics ECM and enables efficient encapsulation of therapeutically active agents which accelerates the wound healing. The nanofibrous scaffold designed herein are in the range of 120 nm to 200 nm dimeter. The nanofibers were processed between 10-15kV and found to be smooth.
The electrospun nanofibrous scaffold has potential attributes for wound healing. The incorporation of zinc oxide nanoparticle impart antibacterial potential to the scaffold. Moreover, Quercetin loading has equipped the scaffold with antioxidant, antibacterial and anti-inflammatory properties that promotes the healing and improves the wound contraction.
The above mentioned, factors can contribute to the design of non-woven nanofibrous dressing as competent and potential wound patch to treat chronic wounds specifically diabetic wounds that undergo amputation if treatment is delayed. The particular invention has the capability to cure diabetic wound as well as recover scar formation on the skin.
Fabrication of scaffold: To prepare the spinning solution, PAN (10% w/w) was dissolved in DMF and ZnO (0.5 wt %) and Quercetin (0.5 wt %) was loaded and stirred for 24h at 500 rpm. The solution was poured in 10 mL syringe fitted with positive Cu electrode connected with a capillary tip. The distance between the capillary tip and collector was 12 cm and the applied voltage was 11.2 kV and a flow rate of 1.3 mL/h. The nanofibers ejected from the capillary tip were collected on aluminum foil wrapped at negatively charged collector.
The electrospun nanofibers were analyzed for their surface morphology by scanning electron microscopy (SEM) (Model; JSM-5300, Japan). Diameter of prepared nanofibers were calculated through image J software by taking random measurements.
The XRD analysis of prepared nanofibers was performed at ambient temperature with sample of nanofiber on a Rotaflex RT300 mA (Rigaku manufacturer, Osaka, Japan) and nickel-filtered Cu. Ka radiation was used for measurements, along with an angular angle of 5 ≤ 2θ ≤ 80°. The XRD pattern of pristine PAN nanofiber, PAN/ZnO nanofiber and PAN/ZnO/Que nanofibers are illustrated in
The FTIR analysis was performed to understand the possible structure of prepared nanofibrous scaffold as illustrated in
Further, in vitro, and in-vivo studies were performed to evaluate the wound healing potential of the PAN/ZnO/Que nanofibers. The % wound contraction of excision wound was measured at different time points after treatment with the nanofiber and it was observed that at day 15 the wound was completely healed compared to the control as illustrated in
