Limits...
Fabrication of surface plasmon resonance sensor surface with control of the non-specific adsorption and affinity for the detection of 2,4,6-trinitrotoluene using an antifouling copolymer.

Yatabe R, Onodera T, Toko K - Front Bioeng Biotechnol (2014)

Bottom Line: We fabricated a surface plasmon resonance (SPR) sensor using a hydrophilic polymer for the highly sensitive detection of 2,4,6-trinitrotoluene (TNT).The detection of TNT was carried out by displacement assay with the SPR measurement.In displacement assay, the affinity between anti-TNT antibody and the sensor surface, affects to the sensitivity.

View Article: PubMed Central - PubMed

Affiliation: Research and Development Center for Taste and Odor Sensing, Kyushu University , Fukuoka , Japan.

ABSTRACT
We fabricated a surface plasmon resonance (SPR) sensor using a hydrophilic polymer for the highly sensitive detection of 2,4,6-trinitrotoluene (TNT). The hydrophilic polymer was made from mono-2-(methacryloyloxy)ethylsuccinate (MES) and 2-hydroxyethylmethacrylate (HEMA) by surface-initiated atom transfer radical polymerization. The detection of TNT was carried out by displacement assay with the SPR measurement. In displacement assay, the affinity between anti-TNT antibody and the sensor surface, affects to the sensitivity. In the SPR measurement, non-specific adsorption should be controlled because SPR sensor cannot discriminate between specific and non-specific adsorption. Therefore, the affinity and non-specific adsorption were controlled by changing the ratio of HEMA to MES. A detection limit of 0.4 ng/ml (ppb) for TNT was achieved using a sensor surface with the lowest affinity without non-specific adsorption.

No MeSH data available.


Related in: MedlinePlus

Fabrication procedure of polymer-based sensor surface by SI-(AGET)ATRP.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4126440&req=5

Figure 1: Fabrication procedure of polymer-based sensor surface by SI-(AGET)ATRP.

Mentions: SIA Kit Au (GE Healthcare Bioscience), which contains sensor chips with an unmodified gold layer of ca. 50 nm thickness, was used for the immobilization of various reagents on the surface. Figure 1 shows the fabrication procedure of a sensor surface using SI-ATRP. This figure shows the case in which the monomers were not mixed to simplify the explanation. First, the sensor chip was cleaned in a mixed solution of Milli-Q water, ammonia solution, and hydrogen peroxide with a 5:1:1 volume ratio at 90°C for 20 min. After that, the sensor chip was immersed in 1 mM DTBU (in ethanol) for 24 h at 18°C to form an SAM with an initiator for ATRP. After the sensor chip was cleaned in ethanol by ultrasonic cleaning, it was immersed in a reaction solution at 40°C to induce activator-generated electron transfer for atom transfer radical polymerization (AGET–ATRP). The reaction solution was prepared by mixing a monomer, a catalyst solution, and a reducing agent. The catalyst solution was a mixed solution of 1 mM CuCl2 and 10 mM TPMA in N,N-dimethylformamide (DMF). The reducing agent was a 1 mM ascorbic acid solution in DMF. These solutions were degassed in vacuum for 1.5 h, and mixed immediately before the polymerization. The reaction solution contained the monomer, CuCl2, TPMA, and ascorbic acid. After the polymerization, the reaction solution was removed using DMF. The thickness of the polymer layer in air was measured using a SpecEl-2000-VIS spectroscopic ellipsometer (Mikropack GmbH, Germany). Table 1 shows the reaction conditions and the thickness of the polymer layer under each set of conditions. These reaction conditions were adjusted to obtain polymer layers with about 10 nm thickness. Then, the sensor chip was immersed in a mixed solution of 0.4 M EDC (in water) and 0.1 M NHS (in DMF) at a 1:1 volume ratio for 1 h to activate the carboxyl groups of the polymer as NHS esters. Next, the chip was immersed in 10 mM DNP-Hdrz (in DMF) for 1 h to combine the amino group of the DNP-Hdrz and the activated carboxyl group of the polymer. Then, the chip was immersed in 0.5 wt.% sodium dodecyl sulfate for cleaning. Finally, it was rinsed in Milli-Q water to complete the fabrication of the sensor chip with binding sites of an anti-TNT antibody on the polymer.


Fabrication of surface plasmon resonance sensor surface with control of the non-specific adsorption and affinity for the detection of 2,4,6-trinitrotoluene using an antifouling copolymer.

Yatabe R, Onodera T, Toko K - Front Bioeng Biotechnol (2014)

Fabrication procedure of polymer-based sensor surface by SI-(AGET)ATRP.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4126440&req=5

Figure 1: Fabrication procedure of polymer-based sensor surface by SI-(AGET)ATRP.
Mentions: SIA Kit Au (GE Healthcare Bioscience), which contains sensor chips with an unmodified gold layer of ca. 50 nm thickness, was used for the immobilization of various reagents on the surface. Figure 1 shows the fabrication procedure of a sensor surface using SI-ATRP. This figure shows the case in which the monomers were not mixed to simplify the explanation. First, the sensor chip was cleaned in a mixed solution of Milli-Q water, ammonia solution, and hydrogen peroxide with a 5:1:1 volume ratio at 90°C for 20 min. After that, the sensor chip was immersed in 1 mM DTBU (in ethanol) for 24 h at 18°C to form an SAM with an initiator for ATRP. After the sensor chip was cleaned in ethanol by ultrasonic cleaning, it was immersed in a reaction solution at 40°C to induce activator-generated electron transfer for atom transfer radical polymerization (AGET–ATRP). The reaction solution was prepared by mixing a monomer, a catalyst solution, and a reducing agent. The catalyst solution was a mixed solution of 1 mM CuCl2 and 10 mM TPMA in N,N-dimethylformamide (DMF). The reducing agent was a 1 mM ascorbic acid solution in DMF. These solutions were degassed in vacuum for 1.5 h, and mixed immediately before the polymerization. The reaction solution contained the monomer, CuCl2, TPMA, and ascorbic acid. After the polymerization, the reaction solution was removed using DMF. The thickness of the polymer layer in air was measured using a SpecEl-2000-VIS spectroscopic ellipsometer (Mikropack GmbH, Germany). Table 1 shows the reaction conditions and the thickness of the polymer layer under each set of conditions. These reaction conditions were adjusted to obtain polymer layers with about 10 nm thickness. Then, the sensor chip was immersed in a mixed solution of 0.4 M EDC (in water) and 0.1 M NHS (in DMF) at a 1:1 volume ratio for 1 h to activate the carboxyl groups of the polymer as NHS esters. Next, the chip was immersed in 10 mM DNP-Hdrz (in DMF) for 1 h to combine the amino group of the DNP-Hdrz and the activated carboxyl group of the polymer. Then, the chip was immersed in 0.5 wt.% sodium dodecyl sulfate for cleaning. Finally, it was rinsed in Milli-Q water to complete the fabrication of the sensor chip with binding sites of an anti-TNT antibody on the polymer.

Bottom Line: We fabricated a surface plasmon resonance (SPR) sensor using a hydrophilic polymer for the highly sensitive detection of 2,4,6-trinitrotoluene (TNT).The detection of TNT was carried out by displacement assay with the SPR measurement.In displacement assay, the affinity between anti-TNT antibody and the sensor surface, affects to the sensitivity.

View Article: PubMed Central - PubMed

Affiliation: Research and Development Center for Taste and Odor Sensing, Kyushu University , Fukuoka , Japan.

ABSTRACT
We fabricated a surface plasmon resonance (SPR) sensor using a hydrophilic polymer for the highly sensitive detection of 2,4,6-trinitrotoluene (TNT). The hydrophilic polymer was made from mono-2-(methacryloyloxy)ethylsuccinate (MES) and 2-hydroxyethylmethacrylate (HEMA) by surface-initiated atom transfer radical polymerization. The detection of TNT was carried out by displacement assay with the SPR measurement. In displacement assay, the affinity between anti-TNT antibody and the sensor surface, affects to the sensitivity. In the SPR measurement, non-specific adsorption should be controlled because SPR sensor cannot discriminate between specific and non-specific adsorption. Therefore, the affinity and non-specific adsorption were controlled by changing the ratio of HEMA to MES. A detection limit of 0.4 ng/ml (ppb) for TNT was achieved using a sensor surface with the lowest affinity without non-specific adsorption.

No MeSH data available.


Related in: MedlinePlus