Microneedles and Their Application in Transdermal Delivery of Antihypertensive Drugs-A Review

Abstract

One of the most cutting-edge, effective, and least invasive pharmaceutical innovations is the utilization of microneedles (MNs) for drug delivery, patient monitoring, diagnostics, medicine or vaccine delivery, and other medical procedures (e.g., intradermal vaccination, allergy testing, dermatology, and blood sampling). The MN-based system offers many advantages, such as minimal cost, high medical effectiveness, comparatively good safety, and painless drug application. Drug delivery through MNs can possibly be viewed as a viable instrument for various macromolecules (e.g., proteins, peptides, and nucleic acids) that are not efficiently administered through traditional approaches. This review article provides an overview of MN-based research in the transdermal delivery of hypertensive drugs. The critical attributes of microneedles are discussed, including the mechanism of drug release, pharmacokinetics, fabrication techniques, therapeutic applications, and upcoming challenges. Furthermore, the therapeutic perspective and improved bioavailability of hypertensive drugs that are poorly aqueous-soluble are also discussed. This focused review provides an overview of reported studies and the recent progress of MN-based delivery of hypertensive drugs, paving the way for future pharmaceutical uses. As MN-based drug administration bypasses first-pass metabolism and the high variability in drug plasma levels, it has grown significantly more important for systemic therapy. In conclusion, MN-based drug delivery of hypertensive drugs for increasing bioavailability and patient compliance could support a new trend of hypertensive drug delivery and provide an alternative option, overcoming the restrictions of the current dosage forms.

Keywords: hypertension; lipid nanoparticles; microneedle; polymeric nanoparticles; transdermal.

Figure 6

Various casting and molding techniques are used for the preparation of MNs ((Figure reproduced with modification (Modified form Bhatnagar and group, 2019 [119]).

Figure 1

Microneedle-based drug delivery through the skin.

Figure 2

Classification of drugs used in hypertension.

Figure 3

Algorithm for hypertension management (JNC-8 guidelines).

Figure 4

Summary of microneedles and their applications.

Figure 5

The drug delivery through different types of microneedles, i.e., hollow microneedles (poke and flow method), dissolving microneedles (poke and release method), solid microneedles (poke and patch method), coated microneedles (coat and poke method), and hydrogel-forming microneedles (poke and release method) as shown by Al-Japairai et al. 2022) [99].

Figure 7

Figure showing steps for in-plane silicon microneedle fabrication as shown by Howells, et al., 2022 [121]. Silicon wafers are represented in blue, silicon dioxide is shown in brown and photoresist is shown in black.

Figure 8

Schematic illustration of polymeric microneedle fabrication via polydimethylsiloxane PDMS micro molding (Figure modified from Wang M et al., 2017 [122]).

Figure 9

Mechanism of action of MNs. Blue color represents a fast drug releasing mechanism, while red color indicates a slow-release mechanism.