fabrication-ultra-sharp-polymeric-microneedles-via-computer-numerical

Fabrication of Ultra-sharp Polymeric Microneedles <em>via</em> Computer Numerical Control (CNC) Micromachining and Micromolding

Microneedles have recently gained recognition as a promising method in transdermal drug delivery owing to their minimally invasive, painless nature, and ...

fabrication-circular-cross-section-microchannels-with-stenosis-via

Fabrication of Circular Cross-section Microchannels with Stenosis via DLP 3D Printing and PDMS Membrane Inflation for Microfluidic Vascular Models

Microfluidic models mimicking the complex architecture of biological vessels require circular cross-sectional channels to accurately simulate hemodynamic ...

International University, Ho Chi Minh City, Vietnam

Vietnam National University, Ho Chi Minh City, Vietnam

International University

Vietnam National University Ho Chi Minh City

Transdermal drug delivery (TDD) has significantly advanced medical practice in recent years due to its ability to prevent the degradation of substances in the gastrointestinal tract and avoid hepatic metabolism. Among different available approaches, microneedle arrays (MNAs) technology represents a fascinating delivery tool for enhancing TDD by penetrating the stratum corneum painless and minimally invasive for delivering antibacterial, antifungal, and antiviral medications. Polymeric MNAs are extensively utilized among many available materials due to their biodegradability, biocompatibility, and low toxicity. Therefore, this review provides a comprehensive discussion of polymeric MNAs, starting with understanding stratum corneum and developing MNA technology. Furthermore, the engineering concepts, fundamental considerations, challenges, and future perspectives of polymeric MNAs in clinical applications are properly outlined, offering a comprehensive and unique overview of polymeric MNAs and their potential for a broad spectrum of clinical applications.

Panoramic review on polymeric microneedle arrays for clinical applications.

Microneedle technology has emerged as an advanced method for transdermal drug delivery, which focuses on diverse fabrication techniques to develop microneedles with various models and geometries. This study explores the application of Computer Numerical Control (CNC) milling technology to create microneedle master molds with extremely sharp tips. We examined the effects of two key machining parameters, feed rate and ramp angle, on the tip sharpness of the microneedles. Our results showed that increasing both the feed rate and ramp angle could significantly reduce machining time. However, a higher feed rate also led to larger tip diameters and notable tip defects. Conversely, changes in the ramp angle at a constant feed rate had minimal impact on tip size. We identified an optimal condition balancing cutting time and tip sharpness at a feed rate of 100 mm/min and a ramp angle of 1.5°. Additionally, we assessed the CNC's capability to produce needles with different tip angles. The findings confirm that needles with varying tip angles maintained tip diameters below 10 μm, with needles having a 50° tip angle exhibiting the sharpest tips at approximately 3.3 μm. Further compression, insertion and diffusion tests were conducted to evaluate the performance of needles with different geometries.

Optimizing CNC milling parameters for manufacturing of ultra-sharp tip microneedle with various tip angles.

Over the last decades, three-dimensional (3D) printing has emerged as one of the most promising alternative tissue and organ regeneration technologies. Recent advances in 3D printing technology, particularly in hydrogel-derived bioink formulations, offer promising solutions for fabricating intricate, biomimetic scaffolds that promote vascularization. In this review, we presented numerous studies that have been conducted to fabricate 3D-printed hydrogel vascularized constructs with significant advancements in printing integumentary systems, cardiovascular systems, vascularized bone tissues, skeletal muscles, livers, and kidneys. Furthermore, this work also discusses the engineering considerations, current challenges, proposed solutions, and future outlooks of 3D bioprinting.

ArticleTotal : 2	Year
Publication title Cited by 1	2025
Publication title	2026

Article	Year
Panoramic review on polymeric microneedle arrays for clinical applications. Biomedical microdevices\| PubMed ID: 39312013	2024
Optimizing CNC milling parameters for manufacturing of ultra-sharp tip microneedle with various tip angles. Drug delivery and translational research\| PubMed ID: 39557783	2025
Advances in three-dimensional printing of hydrogel formulations for vascularized tissue and organ regeneration. Journal of biomaterials science. Polymer edition\| PubMed ID: 39899080	2025

Thanh-Qua Nguyen

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