Fabrication of protein microarrays using the electrospray deposition (ESD) method: Application of microfluidic chips in immunoassay

Abstract

In this study, antibody-based protein microarrays for high-throughput immunoassay were fabricated on an aldehydemodified indium-tin oxide glass plate using the electrospray deposition (ESD) method and their characteristics were evaluated immunochemically. The microarrays were also integrated into microfluidic chips with a polydimethylsiloxane (PDMS) micro-channel to detect human cytokines, which were quantitatively analyzed with a high resolution chargecoupled device. Simultaneous detection of various antigens was performed using the microarrays with considerable sensitivity (ca. 100 pg/mL). The results of this study indicate that microfluidic chip comprising a protein microarray formed by the ESD method and a PDMS micro-channel could be easy to handle, and offers high-throughput detection of molecular biomarkers. © KSBB hÉóïçêÇëW=ÉäÉÅíêçëéê~ó=ÇÉéçëáíáçå=ãÉíÜçÇI=éêçíÉáå=ãáÅêç~êê~óI=ÄáçÅÜáéI=ÜáÖÜJíÜêçìÖÜéìí=fããìåç~ëë~ó= = = = =

Fabrication of a New, Low-Cost, and Environment-Friendly Laccase-Based Biosensor by Electrospray Immobilization with Unprecedented Reuse and Storage Performances

“…Furthermore, the ESD process that can be easily automated requires a very small amount of material to be sprayed, making deposition possible in safe, compact, and portable devices. ESD saw its first application in nuclear physics to fabricate a thin layer of radioactive material as a source of high-energy particles (α or β). ,− Later, the method was applied to molecules, over a wide range of molecular weights, for example, low-weight molecules, synthetic polymers, proteins, and DNA. ,,− Thus, ESD has been employed in the formation of layers of semiconductive ceramics such as metal-oxide films, modification of silicon surfaces with layers of silk-forming peptides to enhance the adhesion of living cells, preparation of DNA and protein samples for scanning tunneling microscopy, formation of protective polymer coatings on electrode surfaces, as well as applications for biosensors and biochips (e.g., protein-/DNA-microarray and microfluidic devices), , antifouling or biocompatible coatings for medical devices, high-performance filter media, biomaterial scaffolds for tissue engineering, − nanotechnology, and nanoelectronics . Moreover, the combination of high-flux ESI sources with mass spectrometric selection in vacuum led to the deposition of polyatomic ions with well-defined composition, charge states, and kinetic energy to prepare controlled interfaces for applications in energy storage, catalysis, soft materials, and biology. ,, Among all these applications, ESD has also been used to prepare surfaces with ceramic, nanoparticles, or polymer coatings designed to accept bioactive species or to inhibit bacterial adhesion to enhance cell growth and to immobilize proteins for in situ analysis with other techniques, , as well as to write two-dimensional (2D) metallic nanostructured patterns for surface-enhanced Raman spectroscopy using silver nanoparticles. , …”

Development of immunoassays for protein analysis on nanobioarray chips

“…In other words, this method of detection will be inaccurate if the substrate is not introduced to all detection regions or wells simultaneously (Yakovleva et al, 2002). This method is excellent for high throughput detection, but light shielding from other wells (usually white) is required in order to prevent any residual light from bleeding into other wells, causing false positives (Lee et al, 2010).…”

Electrospray: More than just an ionization source

“…An example of a high‐throughput immunoassay using an antibody microarray produced by ES was published by Lee et al. [112]. Using an array of 324 spots with deposited antibodies (produced in 20 min) on an ITO glass, they were able to spatially detect a fluorescently labeled antigen complexed to an antibody with a sensitivity of 1 ng/mL using a CCD camera.…”

“…Microarrays have been attracting increasing attention particularly due to a remarkable increase in the throughput of sensing and diagnostic assays [111]. Due to the monodispersity of the generated droplets/particles, it is relatively easy to produce microarrays consisting of spots of identical sizes (tens of microns) by using a stencil mask placed between the emitter and the counter electrode [109,112].…”