Low-Cost, Low-Impedance Polyimide Based Micro-Needle Array (PI-MNA): A Minimally Invasive Flexible Dry Electrode for Surface Bio-Potential Monitoring

Li, Junshi; Shen, Zhengkun; Wang, Hancong; Huang, Dong; Chen, Yufeng; Mou, Qun; Zheng, Fengyi; Liu, Junhua; Li, Zhihong

doi:10.1109/memsys.2019.8870653

Cited by 10 publications

(7 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The above-mentioned biodegradable polymers are obviously no longer intact after administration since the collapse of polymers begins once the microneedles are pressed into skin. Therefore, biocompatible polymers like PDMS [41,91], polyimide (PI) [55,56], SU-8 [96], and epoxy [93] are usually selected. Moreover, for specific applications known as electrophysiological interaction (section 3.3), one or more layers of conductive materials should be deposited onto the surface of the micromolded polymer microneedles.…”

Section: Non-biodegradable Materialsmentioning

confidence: 99%

“…Due to the interspace of negative microneedle-shaped holes are too narrow to allow the casted liquid filling up spontaneously, vacuumization [40,43,46,48,55,56,59,92], centrifugation [47,[49][50][51][52][53]55] and positive pressure [42,45] are often employed to drive the liquid into the negative holes. Gao et al [43] added silk fibroin into the microneedles before casting the PEGDA prepolymer solution.…”

Section: Swellable Materialsmentioning

confidence: 99%

“…On the contrary, when an electrical signal of certain intensity and frequency is transmitted to a specific tissue site, the physiological state can be affected. Flexible devices containing microneedles have been successfully applied in electrophysiological interactions, such as surface bioelectrical recording [56,62,64,69,77,80,82], electrotactile display [66][67][68], implantable neural interface [60,61,74,86,87,89,201], and so on, in both animals and humans.…”

Section: Electrophysiological Interactionmentioning

confidence: 99%

See 2 more Smart Citations

Recent advances on fabrication of microneedles on the flexible substrate

Huang

et al. 2021

J. Micromech. Microeng.

View full text Add to dashboard Cite

Microneedles are able to penetrate into the skin and offer great chances in various biomedical applications including transdermal drug delivery, stable bio-signal monitoring, sampling and bio-sensing. Owing to the micro-scale feature size, microneedles have advantages of minimal invasiveness, pain, high biosafety and simple operation. However, it is still challenging to fabricate solid microneedles on a flexible substrate. This review primarily introduces recent studies about microneedles on the flexible substrate, various fabrication methods of microneedles on the flexible substrate, including micromolding, silicon dry/wet etching, electrochemical etching, drawing-lithography, electro-drawing lithography, magnetorheological drawing lithography, three-dimensional printing, vapor–liquid–solid grown, hot embossing, and assembly, and corresponding materials have been summarized and discussed in details. In the end, regular biomedical applications of microneedle on the flexible substrate are categorized into drug delivery, vaccine delivery, electrophysiological interaction, sampling and bio-sensing. Recent advances of each application have been discussed.

show abstract

Section: Non-biodegradable Materialsmentioning

confidence: 99%

Section: Swellable Materialsmentioning

confidence: 99%

Section: Electrophysiological Interactionmentioning

confidence: 99%

See 1 more Smart Citation

Recent advances on fabrication of microneedles on the flexible substrate

Huang

et al. 2021

J. Micromech. Microeng.

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 99%

“…Using elastomeric molds ensures that the mold can be easily bent at a low bending force to avoid plastic deformation of the MNs. The versatility of the strategy allows it to be compatible with several thermosetting polymers, such as cycloolefin polymers [15] and polyimide, [16] organically modified ceramics, [17] and UV-curable polymers, such as SU-8. [18] As the replication fidelity of micromolding is high, the achievable geometry is limited only by the fabrication process used to generate the master template and the release technique for demolding.…”

Section: Introductionmentioning

confidence: 99%

Robust, Long‐Term, and Exceptionally Sensitive Microneedle‐Based Bioimpedance Sensor for Precision Farming

et al. 2021

View full text Add to dashboard Cite

Precision farming has the potential to increase global food production capacity whilst minimizing traditional inputs. However, the adoption and impact of precision farming are contingent on the availability of sensors that can discern the state of crops, while not interfering with their growth. Electrical impedance spectroscopy offers an avenue for nondestructive monitoring of crops. To that end, it is reported on the deployment of impedimetric sensors utilizing microneedles (MNs) that can be used to pierce the waxy exterior of plants to obtain sensitive impedance spectra in open‐air settings with an average relative noise value of 3.83%. The sensors are fabricated using a novel micromolding and release method that is compatible with UV photocurable and thermosetting polymers. Assessments of the quality of the MNs under scanning electron microscopy show that the replication process is high in fidelity to the original design of the master mold and that it can be used for upward of 20 replication cycles. The sensor's performance is validated against conventional planar sensors for obtaining the impedance values of Arabidopsis thaliana. As a change is detected in impedance due to lighting and hydration, this raises the possibility for their widespread use in precision farming.

show abstract