A Novel Method of Immobilizing Antibodies on a Quartz Crystal Microbalance Using Plasma-Polymerized Films for Immunosensors

Abstract

A novel method of immobilizing antibodies on quartz crystals for use in immunosensors was developed using an ethylenediamine plasma-polymerized film matrix. The films formed on the quartz crystals are extremely thin and homogeneous, and they incorporate amino groups. Sensors produced using this method are more reproducible from sample to sample and exhibit lower noise and higher sensitivity than sensors made using conventional immobilization methods, e.g., via polyethylenimine and (gamma-aminopropyl)trimethoxysilane. This is, to our knowledge, the first reported application of plasma-polymerized films to quartz crystal microbalance immunosensors. Results on orientation-controlled immobilization of anti-bodies, reusability and calibration tests are also presented.

Sensor Chip Using a Plasma-polymerized Film for Surface Plasmon Resonance Biosensors: Reliable Analysis of Binding Kinetics

“…immunosensors) using PPFs as a coating film on gold electrodes. [11][12][13] In the present report, we demonstrate that using Sensor Chip PPF reduces the effect by mass transport limitation compared with using "Sensor Chip CM5" (carboxylated dextran hydrogel matrix), which is the conventional chip.…”

“…12,13 Results and Discussion Figure 1 is a schematic illustration of the SPR sensor chip on which the gold surface is modified by carboxylated dextran (Sensor Chip CM5) 14 and PPF (Sensor Chip PPF). Under normal use, good adhesion of the matrix to the gold surface is achieved by adsorption of long-chain ω-hydroxyalkylthiols to generate a self-assembled monolayer, also called the "linker layer" (Fig.…”

X-ray Photoelectron Spectroscopy, Time-of-Flight Secondary Ion Mass Spectrometry, and Principal Component Analysis of the Hydrolysis, Regeneration, and Reactivity of N-Hydroxysuccinimide-Containing Organic Thin Films

“…The novel combination of these analysis methods allowed systematic and sensitive examination of various aspects of NHS-OEG 7 SAMs surface hydrolysis, including cleavage of covalent NHS groups, contamination by adventitious hydrocarbon deposition, thiol oxidation and removal of both NHS and OEG SAM chemistry into aqueous media. XPS data yielded quantitative information for surface elemental composition as well as the carbon and sulfur species in treated NHS-OEG 7 surfaces.…”

“…Possible structures of the prominent peaks for the positive and negative ion spectra are proposed in Table S2 and Table S3, respectively. Multi-variate ratios from ToF-SIMS used for determining the (a) NHS reactivity (Bound_NHS ratio) from the positive ion spectra, (b) thin film thickness (TFT ratio) from the positive ion spectra and (c) sulfur oxidation (SO ratio) from the negative ion spectra of NHS-OEG 7 SAMs on gold after aging treatments that include fresh NHS (Fresh), 1-hr aged (1-hr), 3-day aged (3-d), 7-day aged (7-d), 100% r.h. (100) and hydrolyzed (Water) surfaces. Table 1 XPS-determined elemental compositions for NHS-OEG 7 SAMs on gold after various treatments.…”

Amperimetric Biosensor Based on Carbon Nanotube and Plasma Polymer

“…Allylamine PPs were subsequently widely used in biomedical applications (Mahoney et al, 2004;Kurosawa et al, 2002;Basarir et al, 2007;Zhang et al, 2003;Zhang et al, 2005). The PP surfaces of ethylenediamine (EDA) and alkylamines have amino groups and have also been used in biomedical applications (Jung et al, 2006;Nakanishi et al, 1996;. The resulting film is sometimes different from that of the original monomer structure, because the plasma polymerization process involves fragmentation and reorganization in the presence of highly energetic active species.…”