AgNPs-Modified Polylactic Acid Microneedles: Preparation and In Vivo/In Vitro Antimicrobial Studies.

Abstract

OBJECTIVE:

To prepare polylactic acid microneedles (PLAMNs) with sustained antibacterial effect to avoid skin infection caused by traditional MNs-based biosensors.

METHODS:

Silver nanoparticles (AgNPs) were synthesized using an in-situ reduction process with polydopamine (PDA). PLAMNs were fabricated using the hot-melt method. A series of pressure tests and puncture experiments were conducted to confirm the physicochemical properties of PLAMNs. Then AgNPs were modified on the surface of PLAMNs through in-situ reduction of PDA, resulting in the formation of PLAMNs@PDA-AgNPs. The in vitro antibacterial efficacy of PLAMNs@PDA-AgNPs was evaluated using agar diffusion assays and bacterial liquid co-culture approach. Wound healing and simulated long-term application were performed to assess the in vivo antibacterial effectiveness of PLAMNs@PDA-AgNPs.

RESULTS:

The MNs array comprised 169 tiny needle tips in pyramidal rows. Strength and puncture tests confirmed a 100% puncture success rate for PLAMNs on isolated rat skin and tin foil. SEM analysis revealed the integrity of PLAMNs@PDA-AgNPs with the formation of new surface substances. EDS analysis indicated the presence of silver elements on the surface of PLAMNs@PDA-AgNPs, with a content of 14.44%. Transepidermal water loss (TEWL) testing demonstrated the rapid healing of micro-pores created by PLAMNs@PDA-AgNPs, indicating their safety. Both in vitro and in vivo tests confirmed antibacterial efficacy of PLAMNs@PDA-AgNPs.

CONCLUSIONS:

In conclusion, the sustained antibacterial activity exhibited by PLAMNs@PDA-AgNPs offers a promising solution for addressing skin infections associated with MN applications, especially when compared to traditional MN-based biosensors. This advancement offers significant potential for the field of MN technology.

• Authors: Wenqin Zhang, Xiaozhen Cai, Xinyi Zhang, Shiqi Zou, Danhong Zhu, Qiulong Zhang, Jianmin Chen
• Journal: Pharmaceutical research (Pharm Res) (Nov 20 2023) ISSN: 1573-904X [Electronic] United States
• PMID: 37985572 (Publication Type: Journal Article)
• Copyright: © 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.