The role of microneedles in the healing of chronic wounds

Chronic wounds occur for several reasons, such as trauma, accidents, and diseases. Diabetes has been one of the primary causes of non-healing wounds, and the number of people with diabetes is increasing in most countries. Wounds in diabetic people have a complex and prolonged treatment process, with high treatment costs to both healthcare providers and patients. They often have severe consequences, such as pain, wound infection, tissue necrosis, and even limb amputation. Various methods have been used to treat chronic wounds, but clinical success has been limited due to inefficient delivery to the wound bed. Microneedles (MNs), as new platforms, can offer an effective treatment, easy to use and non-invasive with less tissue damage, capable of delivering a wide range of drugs to accelerate the wound healing process. Different methods and materials can be used for this technique, and there are different geometric parameters such as needle length, tip angle, shape and radius, together with needle array density to optimize for the most effective treatment. This review paper will investigate the role of MNs in healing chronic wounds and discuss the most recent development in MN-based devices in the field and their effectiveness. The manuscript will also discuss the various types of MNs and their potential applications for delivering therapeutic agents. Finally, the challenges associated with using MNs to heal chronic wounds and future directions in this field are discussed.