Device Processing Challenges for Miniaturized Sensing Systems Targeting Biological Fluids

Abstract

This article presents a review of device processing technologies used in the fabrication of biomedical systems, and highlights the requirements of advanced manufacturing technology. We focus on biomedical systems that perform diagnostics of fluidic specimens, with analytes that are in the liquid phase. In the introduction, we define biomedical systems as well as their versatile applications and the essential current trends. The paper gives an overview of the most important biomolecules that typically must be detected or analyzed in several applications. The paper is structured as follows. First, the conventional architecture and construction of a biosensing system is introduced. We provide an overview of the most common biosensing methods that are currently used for the detection of biomolecules and its analysis. We present an overview of reported biochips, and explain the technology of biofunctionalization and detection principles, including their corresponding advantages and disadvantages. Next, we introduce microfluidics as a method for delivery of the specimen to the biochip sensing area. A special focus lies on material requirements and on manufacturing technology for fabricating microfluidic systems, both for niche and mass-scale production segments. We formulate requirements and constraints for integrating the biochips and microfluidic systems. The possible impacts of the conventional microassembly techniques and processing methods on the entire biomedical system and its specific parts are also described. On that basis, we explain the need for alternative microassembly technologies to enable the integration of biochips and microfluidic systems into fully functional systems.

Package Design Thermal Optimization for Metal-Oxide Gas Sensors by Finite Element Modeling and Infra-Red Imaging Characterization

“…The fluorescence response of CDs decreases with increasing temperature from 20 °C to 80 °C [ 40 ], and the temperature of CDs should be kept below 80 °C. The CD sensors show a fast response time and high selectivity and sensitivity in several practical applications such as heavy-metal sensing [ 40 ], varieties of biological fluids [ 41 ], acetone in human fluids [ 42 ], and antibacterial applications [ 40 ].…”

“…The in-house formulated xerogel-epoxy composite with very low thermal conductivity that played a key role in the presented novel packaging approach can be useful for packaging carbon dot (CD)-based sensors. The fluorescence response of CDs decreases with increasing temperature from 20 • C to 80 • C [40], and the temperature of CDs should be kept below 80 • C. The CD sensors show a fast response time and high selectivity and sensitivity in several practical applications such as heavy-metal sensing [40], varieties of biological fluids [41], acetone in human fluids [42], and antibacterial applications [40].…”

Low-Cost Optical pH Sensor with a Polyaniline (PANI)-Sensitive Layer Based on Commercial Off-the-Shelf (COTS) Components

“…Colorimetry is a particular case of commonly used optical detection methods, which are widely used for fluid analyses in chemical and bio-medical applications [6]. The intensity of the color depends on the concentration of the analyte in the liquid, and the results can be interpreted either directly, without any equipment, or using a dedicated equipment if a high-accuracy measurement is required.…”