Synergistically Detachable Microneedle Dressing for Programmed Treatment of Chronic Wounds

Abstract

Chronic wounds such as diabetic feet undergo a lifetime risk of developing into incurable ulcers. Current treatments for chronic wounds remain unsatisfactory due to the lack of ideal wound dressings that integrate facile dressing change, long‐acting treatment, and high therapeutic efficacy into one system. Herein, a synergistically detachable microneedle (MN) dressing with a dual‐layer structure is presented to enable programmed treatment via one‐time dressing application. Such a dual‐layer dressing MN system (DDMNS) is composed of chitosan (CS) hydrogel dressing (CSHD) on top of a detachable MN patch with a CS tip and a polyvinyl pyrrolidone (PVP) backing substrate incorporated with magnesium (Mg). The synergistic detachment is achieved with the backing Mg/PVP substrate dissolving within minutes due to the local moist environment of the CSHD enhancing the reaction between Mg and inflammation microenvironment. The combined treatment of Mg and panax notoginseng saponins (PNS) loaded in DDMNS achieves antibacterial, neovascularization, and activating a benign immune response so that the three overlapping periods of the inflammation, tissue proliferation, and tissue remodeling of wound healing reach a dynamic balance. This advanced DDMNS provides a facile approach for the programmed treatment of chronic wound management indicating potential value in wound healing and other related biomedical fields.

An antibacterial and proangiogenic double-layer drug-loaded microneedle patch for accelerating diabetic wound healing

“…1c shows the force-displacement curve, where the maximum failure force of the entire microneedle array (10 × 10) was 162 N. Therefore, the maximum failure force of the blank DMN was calculated to be 1.62 N per needle, which was significantly greater than the minimum force required to pierce skin (0.1 N). 28,29 Furthermore, the isolated pig skin and the back skin of an SD rat were used to test the effect of the blank DMN puncture. The blank DMN was applied to the pig skin for 2 min and then removed.…”

Microneedles for in situ tissue regeneration

“…Another approach is to embed other active substances in the base of MNs at the same time, which can effectively provide programmed treatment to damaged tissues [ 91 ]. In addition, this type of MN allows better control of the spatial distribution of the drugs in the target tissue, an advantage that other types of materials such as hydrogels or sponges do not have.…”

Recent Advances in Multifunctional Microneedle Patches for Wound Healing and Health Monitoring

“…[ 126 ] Interestingly, a synergistically detachable MPs with a bilayer structure was designed, composed of chitosan hydrogel dressing and Mg‐doped PVP backing substrate. [ 127 ] The Mg/PVP backing dissolved in the wound area within a few minutes, allowing synergistic separation. Mg and Panax notoginseng saponins are combined to achieve the purpose of antibacterial and promoting wound healing.…”