3D-assembled microneedle ion sensor-based wearable system for the transdermal monitoring of physiological ion fluctuations

Abstract

Monitoring human health is of considerable significance in biomedicine. In particular, the ion concentrations in blood are important reference indicators related to many diseases. Microneedle array-based sensors have enabled promising breakthroughs in continuous health monitoring due to their minimally invasive nature. In this study, we developed a microneedle sensing-array integrated system to continuously detect subcutaneous ions to monitor human health status in real time based on a fabrication strategy for assembling planar microneedle sheets to form 3D microneedle arrays. The limitations of preparing 3D microneedle structures with multiple electrode channels were addressed by assembling planar microneedle sheets fabricated via laser micromachining; the challenges of modifying closely spaced microneedle tips into different functionalized types of electrodes were avoided. The microneedle sensing system was sufficiently sensitive for detecting real-time changes in Ca2+, K+, and Na+ concentrations, and it exhibited good detection performance. The in vivo results showed that the ion-sensing microneedle array successfully monitored the fluctuations in Ca2+, K+, and Na+ in the interstitial fluids of rats in real time. By using an integrated circuit design, we constructed the proposed microneedle sensor into a wearable integrated monitoring system. The integrated system could potentially provide information feedback for diseases related to physiological ion changes.

Advanced and personalized healthcare through integrated wearable sensors (versatile)

“…In this regard, Huang et al developed a stainless steel-based microneedle patch for the simultaneous sensing of calcium, potassium, and sodium ions. 83 The stainless-steel microneedles were modified differently for the detection of different ions as shown in Fig. 10III(a) and (b).…”

Implantable Resistive Strain Sensor-Decorated Colloidal Crystal Hydrogel Catheter for Intestinal Tract Pressure Sensing

“…The human intestine, as a natural and excellently integrated sensor network, can convert environmental stimuli into electrical signals, which are then processed by the brain to produce effective commands. , In recent years, a variety of technologies based on flexible electronics and interventional catheters have been developed to monitor peristaltic stress in the intestine. − Inspired by the sensory characteristics of living organisms, new materials and rational manufacturing methods have been developed to build integrated electronic devices which convert in vivo stress signals into electrical signals to enable rapid monitoring of human physiological activity. − While there have been some promising advances, the exploration of simple device structures to achieve efficient multimodal fusion is still urgently needed.…”

Research Progress of Extracellular Vesicles-Loaded Microneedle Technology

“…Using MNs to deliver drugs to different anatomical sites needs to include sensitive biosensor design and miniature flexible and biocompatible electronics in the assessment [12]. MNs can also be integrated with multiple sensors for detecting skin interstitial fluid (ISF), consistently monitoring ion concentrations, glucose, uric acid, insulin, and serotonin, providing a novel approach for disease diagnosis and prognosis monitoring [16][17][18]. Considering factors such as material composition, shape, structure, mechanical strength, and biodegradability, MNs can be Pharmaceutics 2024, 16, 326 2 of 19 custom-designed for various therapeutic applications [19].…”