Aldawood Faisal Khaled, Andar Abhay, Desai Salil
Industrial Engineering Department, College of Engineering, University of Bisha, Bisha 67714, Saudi Arabia.
Potomac Photonics, Inc., Halethorpe, MD 21227, USA.
Polymers (Basel). 2021 Aug 22;13(16):2815. doi: 10.3390/polym13162815.
Drug delivery through the skin offers many advantages such as avoidance of hepatic first-pass metabolism, maintenance of steady plasma concentration, safety, and compliance over oral or parenteral pathways. However, the biggest challenge for transdermal delivery is that only a limited number of potent drugs with ideal physicochemical properties can passively diffuse and intercellularly permeate through skin barriers and achieve therapeutic concentration by this route. Significant efforts have been made toward the development of approaches to enhance transdermal permeation of the drugs. Among them, microneedles represent one of the microscale physical enhancement methods that greatly expand the spectrum of drugs for transdermal and intradermal delivery. Microneedles typically measure 0.1-1 mm in length. In this review, microneedle materials, fabrication routes, characterization techniques, and applications for transdermal delivery are discussed. A variety of materials such as silicon, stainless steel, and polymers have been used to fabricate solid, coated, hollow, or dissolvable microneedles. Their implications for transdermal drug delivery have been discussed extensively. However, there remain challenges with sustained delivery, efficacy, cost-effective fabrication, and large-scale manufacturing. This review discusses different modes of characterization and the gaps in manufacturing technologies associated with microneedles. This review also discusses their potential impact on drug delivery, vaccine delivery, disease diagnostic, and cosmetics applications.
经皮给药具有诸多优势，如避免肝脏首过代谢、维持稳定的血浆浓度、安全性高以及相较于口服或肠胃外给药途径具有更好的顺应性。然而，透皮给药面临的最大挑战在于，只有数量有限的具有理想理化性质的强效药物能够被动扩散并通过细胞间途径渗透过皮肤屏障，进而通过该途径达到治疗浓度。人们已在开发增强药物透皮渗透的方法上付出了巨大努力。其中，微针是微观尺度的物理增强方法之一，极大地拓展了可用于透皮和皮内给药的药物范围。微针的长度通常为0.1至1毫米。在本综述中，将讨论微针材料、制造工艺、表征技术以及在透皮给药方面的应用。诸如硅、不锈钢和聚合物等多种材料已被用于制造实心、包衣、空心或可溶解的微针。它们在透皮给药方面的意义已得到广泛讨论。然而，在持续给药、疗效、经济高效的制造以及大规模生产方面仍存在挑战。本综述讨论了不同的表征模式以及与微针相关的制造技术差距。本综述还讨论了它们对药物递送、疫苗递送、疾病诊断和化妆品应用的潜在影响。
