Fully integrated wearable impedance cytometry platform on flexible circuit board with online smartphone readout

Abstract

We present a wearable microfluidic impedance cytometer implemented on a flexible circuit wristband with on-line smartphone readout for portable biomarker counting and analysis. The platform contains a standard polydimethylsiloxane (PDMS) microfluidic channel integrated on a wristband, and the circuitry on the wristband is composed of a custom analog lock-in amplification system, a microcontroller with an 8-bit analog-to-digital converter (ADC), and a Bluetooth module wirelessly paired with a smartphone. The lock-in amplification (LIA) system is implemented with a novel architecture which consists of the lock-in amplifier followed by a high-pass filter stage with DC offset subtraction, and a post-subtraction high gain stage enabling detection of particles as small as 2.8 μm using the 8-bit ADC. The Android smartphone application was used to initiate the system and for offline data-plotting and peak counting, and supports online data readout, analysis, and file management. The data is exportable to researchers and medical professionals for in-depth analysis and remote health monitoring. The system, including the microfluidic sensor, microcontroller, and Bluetooth module all fit on the wristband with a footprint of less than 80 cm 2 . We demonstrate the ability of the system to obtain generalized blood cell counts; however the system can be applied to a wide variety of biomarkers by interchanging the standard microfluidic channel with microfluidic channels designed for biomarker isolation.

High-throughput electrical position detection of single flowing particles/cells with non-spherical shape

“…58 Moreover, the device is simple from the microfabrication point of view, because it is based on a coplanar-electrode layout, and it is easy to operate, because no focusing mechanisms are required. Therefore, when coupled with a fully integrated electronics, 59,60 it has the potential for pointof-care testing applications.…”

Noninvasive Featherlight Wearable Compliant “Marine Skin”: Standalone Multisensory System for Deep‐Sea Environmental Monitoring

“…It must be noted that merely changing the substrate from PCB and mounting the same rigid ICs on the flexible PCB does not make it flexible for the desired application. Moreover, many presented flexible systems have flexible sensory parts but the core of the readout circuit is a microcontroller or data acquisition system that in itself is not flexible, also, the sensory platforms are not stand‐alone . Most often, these flexible sensors are connected to the data acquisition system by either wire‐bonding or soldering wired connectors that again make the system vulnerable for failure.…”

“…Moreover, many presented flexible systems have flexible sensory parts but the core of the readout circuit is a microcontroller or data acquisition system that in itself is not flexible, also, the sensory platforms are not stand-alone. [39][40][41] Most often, these flexible sensors are connected to the data acquisition system by either wire-bonding or soldering wired connectors that again make the system vulnerable for failure. Hence, a practical approach toward obtaining a fully compliant system needs absolutely no rigid components.…”

Lab-on-a-chip technologies for diagnosis and monitoring of airway inflammation

“…Ultimately, patients with chronic inflammation will benefit from wearable devices that can continuously monitor health (Fig 1). Furniturewalla et al 9 recently fabricated a smart wristband capable of monitoring biomarkers and cells in bodily fluids. One can envision asthmatic patients with a bracelet or necklace into which they A depiction envisioning the future of respiratory health monitoring using wearable devices and smartphones.…”