Conventional microneedles (MNs) have been extensively reported and applied toward a variety of biosensing and drug delivery applications. Hydrogel forming MNs with the added ability to electrically track health conditions in real‐time is an area yet to be explored. The first conductive hydrogel microneedle (HMN) electrode that is capable of on‐needle pH detection with no postprocessing required is presented here. The HMN array is fabricated using a swellable dopamine (DA) conjugated hyaluronic acid (HA) hydrogel, and is embedded with poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) to increase conductivity. The catechol‐quinone chemistry intrinsic to DA is used to measure pH in interstitial fluid (ISF). The effect of PEDOT:PSS on the characteristics of the HMN array such as swelling capability and mechanical strength is fully studied. The HMN's capability for pH measurement is first demonstrated using porcine skin equilibrated with different pH solutions ranging from 3.5 to 9. Furthermore, the HMN‐pH meter is capable of in vivo measurements with a 93% accuracy compared to a conventional pH probe meter. This HMN technology bridges the gap between traditional metallic electrochemical biosensors and the direct extraction of ISF, and introduces a platform for the development of polymeric wearable sensors capable of on‐needle detection.

To enable personalized and precision medicine, it is crucial to monitor patient health status and bring information on disease-related agents and therapeutic drug molecules into the clinic. This requires new technologies to interrogate different body fluids that are rich sources of biomarkers, such as whole blood and interstitial fluid (ISF). Such technologies enable rapid, sensitive and - ultimately - real-time and continuous analysis of the clinically important biomarkers. Biophysics, materials chemistry and polymer and molecular engineering, as well as micro and nanofabrication, are crucial tools in this endeavor. At IDEATION Lab, we apply innovative engineering solutions to advance patient health monitoring using two main technologies: Microneedles and Microfluidics. In the first part of my talk, I will present our new transdermal biosensing technologies powered by engineered hydrogel microneedles (HMNs), aptamer probes, and in-situ metallic nanoparticle synthesis for minimally invasive, on-needle, and real-time measurement of clinically important biomarkers in ISF. Our HMN assays expect to pave the way for the next-generation of polymeric-based wearable biosensors. In the second part, I will discuss a real-time biosensor driven by microfluidic techniques that continuously updates specific biomolecules’ fluctuating concentration levels with picomolar sensitivity directly in whole blood. For the first time, our microfluidic assay enables measuring the dynamic changes in blood insulin which is an important knowledge gap in diabetes management. The new advances reported in this talk, enrich the level of information that can be collected from different body fluids, and provide new means and potentials for highly accurate patient health status monitoring, thus transforming the field of personalized and precision medicine.