Bulk- and surface-modified combinable PDMS capillary sensor array as an easy-to-use sensing device with enhanced sensitivity to elevated concentrations of multiple serum sample components

Abstract

To enhance sensitivity and facilitate easy sample introduction into a combinable poly(dimethylsiloxane) (PDMS) capillary (CPC) sensor array, PDMS was modified in bulk and on its surface to prepare "black" PDMS coated with a silver layer and self-assembled monolayer (SAM). India ink, a traditional Japanese black ink, was added to the PDMS pre-polymer for bulk modification. The surface was modified by a silver mirror reaction followed by SAM formation using cysteine. These modifications enhanced the fluorescence signals by reflecting them from the surface and reducing background interference. A decrease in the water contact angle led to enhanced sensitivity and easy sample introduction. Furthermore, a CPC sensor array for multiplex detection of serum sample components was prepared that could quantify the analytes glucose, potassium, and alkaline phosphatase (ALP). When serum samples were introduced by capillary action, the CPC sensor array showed fluorescence responses for each analyte and successfully identified the components with elevated concentrations in the serum samples.

Michrochip chromatography using an open‐tubular microchannel and a ternary water–ACN–ethyl acetate mixture carrier solution

“…Such research areas were well-known as micrototal analysis systems (-TAS) or lab-on-a-chip [17]. As one of them, microchip-electrophoresis is widely investigated as a small and rapid separation method.…”

Advancements in Capillary-Assembled Microchip (CAs-CHIP) Development for Multiple Analyte Sensing and Microchip Electrophoresis

“…To address this problem, we have developed combinable PDMS capillary (CPC) technology. [52][53][54] In this capillary biosensor, different reagents can be immobilized independently because the CPC is an assembly of two PDMS microstructures. Overall, it is important to explore new biosensing mechanisms, develop simple fluid handling techniques, and improve the fabrication and design of the micro analytical device to ultimately achieve simultaneous multiplex bioassay capabilities.…”

Fast and Single-step Fluorescence-based Competitive Bioassay Microdevice Combined PDMS Microchannel Arrays Separately Immobilizing Graphene Oxide-Analyte Conjugates and Fluorescently-labelled Receptor Proteins

“…Recently, we proposed designing "singlestep" microdevices based on square glass capillaries [9][10][11][12][13] or polymer capillaries. [14][15][16] For these approaches, the inner capillary wall is functionalized by physical adsorption or covalent bonding of analytical reagents or by coating the wall with reagent-containing films. By integrating all reagents involved in the analysis onto the capillary wall, a rapid response could be achieved based on small reaction scale, low amount of sample, and simple analytical procedure based on the capillary actionmediated introduction of the sample solution.…”