Magnetically actuated dual-valve micropump integrated with hollow microneedles
SENSORS AND ACTUATORS, A: PHYSICAL, cilt.412, sa.118739, ss.1-13, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 412 Sayı: 118739
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.sna.2026.118739
- Dergi Adı: SENSORS AND ACTUATORS, A: PHYSICAL
- Derginin Tarandığı İndeksler: Academic Search Ultimate (EBSCO), Engineering Source (EBSCO), Scopus, Science Citation Index Expanded (SCI-EXPANDED), Chemical Abstracts Core, Chimica, Compendex, INSPEC
- Sayfa Sayıları: ss.1-13
- Hacettepe Üniversitesi Adresli: Evet
Özet
Microneedle (MN) arrays have emerged as minimally invasive interfaces capable of bypassing the stratum corneum barrier to enable efficient transdermal fluid transport. However, achieving precise and programmable flow control requires their integration with active microfluidic components. In this work, a magnetically actuated dual-valve micropump integrated with a hollow microneedle (HMN) array was designed, fabricated, and characterized to establish a compact and direction-dependent microfluidic platform. The poly-L-lactic acid (PLLA) HMN array was produced through a single-step solvent-casting process, eliminating post-fabrication steps while ensuring high structural fidelity and reproducibility. Each truncated-cone HMN (1.4 ± 0.2 mm length, 0.9 ± 0.1 mm base width, 0.20 ± 0.03 mm tip diameter) exhibited a deformation force of 2.9 ± 0.4 N and achieved an effective penetration depth of ~900 µm in an eight-layer Parafilm® model. The micropump, consisting of a flexible PDMS membrane coupled with a neodymium magnet, was wirelessly actuated by an external magnetic pulser (0.7 T, 4 s intervals), inducing periodic membrane deflection. Two integrated elastic microvalves, a non-return valve (NRV) and a diaphragm valve (DV), enabled unidirectional and pressure-sensitive flow regulation. Direction-dependent magnetic actuation yielded two distinct operational modes: a positive-pressure mode (18 ± 0.36 µL min⁻¹) and a negative-pressure mode (7.3 ± 0.65 µL min⁻¹), demonstrating controllable and stable flow characteristics with zero-order kinetics. When evaluated under artificial skin load conditions, the system maintained continuous forward flow with rates of 11 ± 0.55 µL min⁻¹ and 4.3 ± 0.47 µL min⁻¹ in the positive and negative modes, respectively, confirming its ability to overcome insertion-induced hydraulic resistance. By bridging magnetic polarity-driven actuation with HMN-mediated transport, this platform establishes a scalable, wireless, and energy-efficient strategy for controlled transdermal application and on-demand therapeutic administration, offering substantial potential for future lab-on-chip biomedical systems.