Microneedles: One-Plane Bevel-Tipped Fabrication by 3D-Printing Processes

Abstract

This article presents microneedles analyses where the design parameters studied included length and inner and outer diameter ranges. A mathematical model was also used to generalize outer and inner diameter ratios in the obtained ranges. Following this, the range of inner and outer diameters was completed by mechanical simulations, ranging from 30 μm to 134 μm as the inner diameter range and 208 μm to 250 μm as the outer diameter range. With these ranges, a mathematical model was made using fourth-order polynomial regressions with a correlation of 0.9993, ensuring a safety factor of four in which von Misses forces of the microneedle are around 17.931 MPa; the ANSYS software was used to analyze the mechanical behavior of the microneedles. In addition, the microneedle concept was made by 3D printing using a bio-compatible resin of class 1. The features presented by the microneedle designed in this study make it a promising option for implementation in a transdermal drug-delivery device.

Development of an Automated Design Tool for FEM-Based Characterization of Solid and Hollow Microneedles

“…Villota et al [ 43 ] chose a bevel cylinder as the geometry under study, although two different tip terminations are considered. On the one hand, the traditional 1-bevel tip is characterized by a single surface with a 45° tip angle.…”

“… Type of MN Ref. Material Used Material Properties Geometry Dimensions Applied Load Reported Results Array Size Fabrication Method Application Solid In-plane [ 42 ] Silicon E = 169 GPa σ y = 7 GPa Rectangular with sharp tip and triangular L = 1.5–3 mm W b = 300–500 μm T b = 500 μm θ = 5–30° F t = 2.5 N with P in = 6.36 MPa Post etching Stress 2.85 GPa Buckling SF > 1 1 × 1 1 × 5 Post-CMOS compatible N/r Hollow Out-of-plane [ 43 ] Class I biocompatible resin E = 2.9 GPa σ y = 73 MPa ν = 0.35 1-bevel tip L = 450 μm D b = 208–250 μm D i = 30–134 μm θ = 45° F a = 0.5 N Min D i /max D b Stress 12.4 MPa Strain 15.4 × 10 −4 1 × 1 3D printing TDD 3-bevel tip θ 1 = 30° θ 2 = 35° …”

Praticas Em Saúde: Uma Abordagem Multidisciplinar

“…Dessa forma, Sistemas de Administração Transdérmica de Medicamentos (Transdermal drug delivery -TDDs), como as microagulhas (MNs) vêm sendo desenvolvidos como estratégia para superar essas barreiras, de modo a melhorar a penetração do fármaco na pele. Esses sistemas também têm ganhado destaque por apresentar outras vantagens, em comparação aos métodos convencionais de administração, como a melhoria da biodisponibilidade de substâncias ativas instáveis, por apresentar efeito local e sistêmico e por não causar dor na aplicação, tornando-o um método confortável para o paciente (Filho et al, 2023;Villota et al, 2022). Além disso, pode ser utilizado para administração de medicamentos e vacinas sem o uso de injeções (Al-Nimry e Daghmash, 2023).…”