Engineering Nanostructured Lipid Carriers for Effective Topical and Dermal Drug Delivery

Abstract

Topical drug delivery has emerged as an attractive strategy for treating skin disorders and for improving patient comfort when systemic therapy is needed. Unlike oral or injectable routes, topical administration is painless and generally leads to better patient compliance. However, effective delivery through the skin remains challenging because the outermost layer of the skin, the stratum corneum, acts as a strong protective barrier. This barrier particularly restricts the passage of hydrophilic drugs, thereby limiting their therapeutic effectiveness. To overcome this limitation, several physical and formulation-based approaches have been explored to enhance drug penetration into and across the skin. The success of topical therapy largely depends on the ability of the formulation to transport the drug safely and efficiently through the skin barrier. Initial efforts in this area focused on liposomes, which opened the door to the development of more advanced Nano carrier systems. Today, Nano carriers are widely recognized as promising vehicles for drug delivery. Among them, nanostructured lipid carriers (NLCs) have attracted particular interest. Their unique structure offers several advantages, including excellent biocompatibility, low toxicity, improved drug loading capacity, and enhanced stability of incorporated drugs. In addition to topical use, NLCs have shown potential in a variety of administration routes such as oral, intravenous, pulmonary, ocular, dermal, and transdermal delivery. This review discusses the key characteristics of NLCs, their methods of preparation, and the techniques used to evaluate their quality and safety. Overall, available evidence suggests that NLCs represent a promising and versatile platform for effective dermal and transdermal drug delivery.