UV-laser-assisted modification of poly(methyl methacrylate) and its application to capillary-driven-flow immunoassay

Abstract

A concave microchannel surface was formed by nanosecond pulse laser ablation to allow antibody immobilization on a capillary flow immunoassay chip. Microscopic analysis showed that UV laser ablation of poly(methyl methacrylate) at 193 nm and 1.76 J · cm−2 allowed excellent immobilization of Cy5 conjugated antibody. The concave structure was 10 µm deep and 260 µm wide and supported uniform antibody printing on the microchannel surface. The characteristics of immobilized antibodies on this surface and on a commercially available polymer coating were comparable. Quantitative analysis of procollagen type I C-peptide (PICP) at different concentrations provided a linear relationship in the range 0–600 ng ml−1 PICP, which is sufficient for clinical estimation of PICP in the blood. The results may provide a new benchmark for a mechatronic antibody immobilization-based capillary flow immunoassay chip.

Capillary-Driven Flow Microfluidics Combined with Smartphone Detection: An Emerging Tool for Point-of-Care Diagnostics

“…Several biomedically relevant biomarkers were studied via capillary-driven flow microfluidics [ 33 , 34 , 35 , 36 , 37 , 38 ]. A capillary flow immunoassay microchip was developed by Fuchiwaki et al [ 33 ] to quantify procollagen type I C-peptide from blood samples. Laser ablation was used to immobilize the antibody on the surface of the PMMA microchannels, which allowed the reaction via movement of liquid in the channels, as shown in the schematic ( Figure 2 d) [ 33 ].…”

“…A capillary flow immunoassay microchip was developed by Fuchiwaki et al [ 33 ] to quantify procollagen type I C-peptide from blood samples. Laser ablation was used to immobilize the antibody on the surface of the PMMA microchannels, which allowed the reaction via movement of liquid in the channels, as shown in the schematic ( Figure 2 d) [ 33 ]. The liquid sample was dropped on the channel inlets which travelled towards the antibody-coated region via capillary force, incubated and flushed out via the outlet and paper absorption.…”

“…Several biomedically relevant biomarkers were studied via capillary-driven flow microfluidics [33][34][35][36][37][38]. A capillary flow immunoassay microchip was developed by Fuchiwaki et al [33] to quantify procollagen type I C-peptide from blood samples.…”

“…Side and top view of the sample pipetting and fluid flow in the microchannel (A,B). Reproduced with permission from [30]; (d) Illustration of the antibody immobilization process (a) with single-channel schematic (b).Reproduced with permission from[33]; (e) Combinable-polydimethylsiloxane (PDMS) capillary sensor array concept illustration. Reproduced with permission from[34]; (f) Combinable-PDMS capillary sensor array analysis of serum components via imaging (a) and fluorescence microscopy (bc).…”

Design and Fabrication of Capillary-Driven Flow Device for Point-Of-Care Diagnostics

“…In another development, PMMA was also used to develop a capillary flow device for nucleic acid biosensing applications using 500 µm-wide microfluidic channels consisting of sealed reagent-loaded pads [7]. Furthermore, capillary-driven flow microfluidics has also been developed for the measurement of biomedically relevant biomarkers [8][9][10][11][12][13]. The dynamics of open microfluidic channels has also been studied via 3D printing of microchannels for rapid prototyping and mass fabrication options [14].…”