Study of the permeation-promoting effect and mechanism of solid microneedles on different properties of drugs

Abstract

In transdermal drug delivery systems, the physicochemical properties of the drug affect its percutaneous permeability. However, whether the physicochemical properties of drugs change their transdermal permeability in the presence of pores in the presence of solid microneedles (MNs) has been less studied in this area. In this project, cinnamaldehyde, curcumin, ferulic acid and geniposide were selected as model drugs for the study of their transdermal permeability under the action of MNs, and a combination of classical experiments and visualization means such as scanning electron microscopy and laser confocal was used to investigate the permeation-promoting mechanism of MNs. The results showed that the MNs had significant permeation-promoting effects on different properties of drugs, with the permeation-promoting effects on cinnamaldehyde, curcumin, ferulic acid and geniposide being 6.36, 17.43, 29.54 and 8.91 times, respectively, and the permeation-promoting effects were more pronounced for lipid-soluble and amphiphilic drugs. Using scanning electron microscopy, transmission electron microscopy and other means to confirm that MNs can promote the penetration by acting on the skin to produce pores, and their effect on skin structure is greater than that of drugs. In addition, the existence of pores increases the amount of drug transdermal, which may enhance the diffusion of drug on the skin, and has no effect on lipid exchange and transdermal route. Through the research, it has been found that MNs is equivalent to direct peeling of the stratum corneum (SC), but it is simpler and safer for the patient.

Applications and prospects of microneedles in tumor drug delivery

“…The height of the needle tip is 100–1000 μm, and the diameter of the needle tip is 1–10 μm. The sharp tips of microneedles can penetrate the skin and tissue for drug delivery to enhance drug penetration, 40 while avoiding contact with blood vessels and nerves, allowing almost painless and noninvasive drug delivery, and minimizing risk of infection. 41 In addition, the neat array structure of microneedles can enable uniform drug delivery and distribution to local tissues and improve the drug availability to local tissues.…”

Key Transdermal Patch Using Cannabidiol-Loaded Nanocarriers with Better Pharmacokinetics in vivo

“…[23][24][25] TDDS offer noninvasiveness, minimal pain, first-pass metabolism bypassing, ease of administration, independence from medical personnel, and potential applicability to a wide range of hydrophilic and hydrophobic drugs. [26][27][28][29][30] However, one limitation of transdermal drug delivery is the difficulty of drug penetration through the human skin, which is hard and resistant to infiltration. 31 The human skin comprises three main layers: the epidermis, dermis, and hypodermis.…”