Microneedle Arrays Combined with Nanomedicine Approaches for Transdermal Delivery of Therapeutics

Abstract

Organic and inorganic nanoparticles (NPs) have shown promising outcomes in transdermal drug delivery. NPs can not only enhance the skin penetration of small/biomacromolecule therapeutic agents but can also impart control over drug release or target impaired tissue. Thanks to their unique optical, photothermal, and superparamagnetic features, NPs have been also utilized for the treatment of skin disorders, imaging, and biosensing applications. Despite the widespread transdermal applications of NPs, their delivery across the stratum corneum, which is the main skin barrier, has remained challenging. Microneedle array (MN) technology has recently revealed promising outcomes in the delivery of various formulations, especially NPs to deliver both hydrophilic and hydrophobic therapeutic agents. The present work reviews the advancements in the application of MNs and NPs for an effective transdermal delivery of a wide range of therapeutics in cancer chemotherapy and immunotherapy, photothermal and photodynamic therapy, peptide/protein vaccination, and the gene therapy of various diseases. In addition, this paper provides an overall insight on MNs’ challenges and summarizes the recent achievements in clinical trials with future outlooks on the transdermal delivery of a wide range of nanomedicines.

Microneedles in Drug Delivery: Progress and Challenges

“…The system has been proven as a valuable technique in delivering drug molecules with higher masses (over 500 Da) and various polarities. The therapeutic ingredients include small molecules; biomacromolecules (proteins, hormones, peptides); vaccines for SARS, MERS, and COVID-19; and genes [2]. In fact, an example of an MN-based system has progressed into phase III clinical trials (www.clinicaltrials.gov, accessed on 1 August 2021).…”

Micro- and Nano-Based Transdermal Delivery Systems of Photosensitizing Drugs for the Treatment of Cutaneous Malignancies

“…NIR-irradiated drug-loaded nanovehicle revealed a synergistic killing effect on melanoma cells through ROS and caspase-activated apoptosis. Tumor regression studies on a xenografted melanoma mouse model highlighted superior therapeutic efficacy of the nanovehicle through combinational PDT and targeted therapy as a promising therapeutic option for malignant melanoma [ 99 ].…”

Microneedle-Mediated Transdermal Delivery of Drug-Carrying Nanoparticles

“…As portable and minimally invasive devices, MN patches that contain hundreds of MNs connecting with supporting layers can effectively overcome the barrier of stratum corneum to facilitate transdermal delivery of nanoparticles that are far greater than pure drugs, either by producing reversible microchannels for enhancing skin permeation of topically applied nanoparticles (e.g., solid MNs), or by getting dissolved under the skin to achieve direct delivery of nanoparticles in the skin (e.g., coated MNs and dissolvable MNs) (Figure 1). Although the topic about transdermal delivery of nanoparticles via MNs has been recently reported by some review papers (Chen et al, 2020;Alimardani et al, 2021;Ruan and Zhang, 2021;Salwa et al, 2021), this work put a different emphasis on this subject that include the design and summarization of drug-carrying nanoparticles integrated with MNs. In this review, we first introduce the four types of nanoparticles capable of carrying drugs, including nanocrystals, lipid nanoparticles, polymeric nanoparticles and inorganic nanoparticles, and then describe MN-based strategies that have been adopted to aid transdermal delivery of these nanoparticles for drug delivery.…”