Limits...
Application of paper-supported printed gold electrodes for impedimetric immunosensor development.

Ihalainen P, Majumdar H, Viitala T, Törngren B, Närjeoja T, Määttänen A, Sarfraz J, Härmä H, Yliperttula M, Österbacka R, Peltonen J - Biosensors (Basel) (2012)

Bottom Line: In this article, we report on the formation and mode-of-operation of an affinity biosensor, where alternate layers of biotin/streptavidin/biotinylated-CRP-antigen/anti-CRP antibody are grown on printed gold electrodes on disposable paper-substrates.We have successfully demonstrated and detected the formation of consecutive layers of supra-molecular protein assembly using an electrical (impedimetric) technique.The article provides a possible biosensor development scheme, where-(1) fabrication of paper substrate (2) synthesis of gold nanoparticle inks (3) inkjet printing of gold electrodes on paper (4) formation of the biorecognition layers on the gold electrodes and (5) electrical (impedimetric) analysis of growth-all are coupled together to form a test-structure for a recyclable and inexpensive point-of-care diagnostic platform.

View Article: PubMed Central - PubMed

Affiliation: Center of Excellence for Functional Materials and Laboratory of Physical Chemistry, Department of Natural Sciences, Åbo Akademi University, Turku, Finland; E-Mails: bjorn.torngren@abo.fi (B.T.); anni.maattanen@abo.fi (A.M.); jawad.sarfraz@abo.fi (J.S.); jouko.peltonen@abo.fi (J.P.).

ABSTRACT
In this article, we report on the formation and mode-of-operation of an affinity biosensor, where alternate layers of biotin/streptavidin/biotinylated-CRP-antigen/anti-CRP antibody are grown on printed gold electrodes on disposable paper-substrates. We have successfully demonstrated and detected the formation of consecutive layers of supra-molecular protein assembly using an electrical (impedimetric) technique. The formation process is also supplemented and verified using conventional surface plasmon resonance (SPR) measurements and surface sensitive characterization techniques, such as X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The article provides a possible biosensor development scheme, where-(1) fabrication of paper substrate (2) synthesis of gold nanoparticle inks (3) inkjet printing of gold electrodes on paper (4) formation of the biorecognition layers on the gold electrodes and (5) electrical (impedimetric) analysis of growth-all are coupled together to form a test-structure for a recyclable and inexpensive point-of-care diagnostic platform.

No MeSH data available.


(A) SPR signal response after injecting 1–20 μg/mL bio-CRP antigen in HEPES-EDTA buffer over MuOH:Biotin-PEG-thiol (85:15 mol%)/streptavidin sensor surface. Down arrows represents the time of bio-CRP antigen injections: 1. = 1 µg/mL, 2. = 2 µg/mL, 3. = 5 µg/mL, 4. = 10 µg/mL and 5. = 20 µg/mL. Up arrows represents the injection of buffer without bio-CRP antigen. (B) Mass areal density of bio-CRP antigen showing the Langmuir fit over the data points.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4263588&req=5

biosensors-03-00001-f003: (A) SPR signal response after injecting 1–20 μg/mL bio-CRP antigen in HEPES-EDTA buffer over MuOH:Biotin-PEG-thiol (85:15 mol%)/streptavidin sensor surface. Down arrows represents the time of bio-CRP antigen injections: 1. = 1 µg/mL, 2. = 2 µg/mL, 3. = 5 µg/mL, 4. = 10 µg/mL and 5. = 20 µg/mL. Up arrows represents the injection of buffer without bio-CRP antigen. (B) Mass areal density of bio-CRP antigen showing the Langmuir fit over the data points.

Mentions: Surface Plasmon Resonance (SPR) gold slides were coated with SAM by immersing the slide in MBP solution (5 mM in ethanol) for 16 h. After thiolation, the substrates were removed from the solution and rinsed immediately with absolute ethanol and dried with nitrogen gas. Immobilization of streptavidin and bio-CRP-antigen was monitored in situ with a SPR instrument (SPR Navi 200, Bionavis Ltd., Tampere, Finland). The SPR Navi 200 instrument has an integrated peristaltic pump and a sample loop system connected to a 6-port valve, which allows injection of sample plugs into the continuously running buffer. For streptavidin and bio-CRP-antigen interaction measurements, the flow channel of the SPR system was first filled with HEPES-EDTA buffer with a constant flow rate of 20 µL/min. After a stable baseline was obtained, solutions with increasing concentrations (ranging from 2.5 to 300 nM for streptavidin, Figure 2, or from 1 to 20 µg/mL for bio-CRP-antigen, Figure 3) were injected as a plug into the continuously flowing buffer stream to measure the specific interaction between streptavidin and the MuOH:Biotin-PEG-thiol (85:15 mol%) SAM sensor surface, or bio-CRP antigen and the MuOH:Biotin-PEG-thiol (85:15 mol%)/streptavidin sensor surface.


Application of paper-supported printed gold electrodes for impedimetric immunosensor development.

Ihalainen P, Majumdar H, Viitala T, Törngren B, Närjeoja T, Määttänen A, Sarfraz J, Härmä H, Yliperttula M, Österbacka R, Peltonen J - Biosensors (Basel) (2012)

(A) SPR signal response after injecting 1–20 μg/mL bio-CRP antigen in HEPES-EDTA buffer over MuOH:Biotin-PEG-thiol (85:15 mol%)/streptavidin sensor surface. Down arrows represents the time of bio-CRP antigen injections: 1. = 1 µg/mL, 2. = 2 µg/mL, 3. = 5 µg/mL, 4. = 10 µg/mL and 5. = 20 µg/mL. Up arrows represents the injection of buffer without bio-CRP antigen. (B) Mass areal density of bio-CRP antigen showing the Langmuir fit over the data points.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4263588&req=5

biosensors-03-00001-f003: (A) SPR signal response after injecting 1–20 μg/mL bio-CRP antigen in HEPES-EDTA buffer over MuOH:Biotin-PEG-thiol (85:15 mol%)/streptavidin sensor surface. Down arrows represents the time of bio-CRP antigen injections: 1. = 1 µg/mL, 2. = 2 µg/mL, 3. = 5 µg/mL, 4. = 10 µg/mL and 5. = 20 µg/mL. Up arrows represents the injection of buffer without bio-CRP antigen. (B) Mass areal density of bio-CRP antigen showing the Langmuir fit over the data points.
Mentions: Surface Plasmon Resonance (SPR) gold slides were coated with SAM by immersing the slide in MBP solution (5 mM in ethanol) for 16 h. After thiolation, the substrates were removed from the solution and rinsed immediately with absolute ethanol and dried with nitrogen gas. Immobilization of streptavidin and bio-CRP-antigen was monitored in situ with a SPR instrument (SPR Navi 200, Bionavis Ltd., Tampere, Finland). The SPR Navi 200 instrument has an integrated peristaltic pump and a sample loop system connected to a 6-port valve, which allows injection of sample plugs into the continuously running buffer. For streptavidin and bio-CRP-antigen interaction measurements, the flow channel of the SPR system was first filled with HEPES-EDTA buffer with a constant flow rate of 20 µL/min. After a stable baseline was obtained, solutions with increasing concentrations (ranging from 2.5 to 300 nM for streptavidin, Figure 2, or from 1 to 20 µg/mL for bio-CRP-antigen, Figure 3) were injected as a plug into the continuously flowing buffer stream to measure the specific interaction between streptavidin and the MuOH:Biotin-PEG-thiol (85:15 mol%) SAM sensor surface, or bio-CRP antigen and the MuOH:Biotin-PEG-thiol (85:15 mol%)/streptavidin sensor surface.

Bottom Line: In this article, we report on the formation and mode-of-operation of an affinity biosensor, where alternate layers of biotin/streptavidin/biotinylated-CRP-antigen/anti-CRP antibody are grown on printed gold electrodes on disposable paper-substrates.We have successfully demonstrated and detected the formation of consecutive layers of supra-molecular protein assembly using an electrical (impedimetric) technique.The article provides a possible biosensor development scheme, where-(1) fabrication of paper substrate (2) synthesis of gold nanoparticle inks (3) inkjet printing of gold electrodes on paper (4) formation of the biorecognition layers on the gold electrodes and (5) electrical (impedimetric) analysis of growth-all are coupled together to form a test-structure for a recyclable and inexpensive point-of-care diagnostic platform.

View Article: PubMed Central - PubMed

Affiliation: Center of Excellence for Functional Materials and Laboratory of Physical Chemistry, Department of Natural Sciences, Åbo Akademi University, Turku, Finland; E-Mails: bjorn.torngren@abo.fi (B.T.); anni.maattanen@abo.fi (A.M.); jawad.sarfraz@abo.fi (J.S.); jouko.peltonen@abo.fi (J.P.).

ABSTRACT
In this article, we report on the formation and mode-of-operation of an affinity biosensor, where alternate layers of biotin/streptavidin/biotinylated-CRP-antigen/anti-CRP antibody are grown on printed gold electrodes on disposable paper-substrates. We have successfully demonstrated and detected the formation of consecutive layers of supra-molecular protein assembly using an electrical (impedimetric) technique. The formation process is also supplemented and verified using conventional surface plasmon resonance (SPR) measurements and surface sensitive characterization techniques, such as X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The article provides a possible biosensor development scheme, where-(1) fabrication of paper substrate (2) synthesis of gold nanoparticle inks (3) inkjet printing of gold electrodes on paper (4) formation of the biorecognition layers on the gold electrodes and (5) electrical (impedimetric) analysis of growth-all are coupled together to form a test-structure for a recyclable and inexpensive point-of-care diagnostic platform.

No MeSH data available.