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A regenerative label-free fiber optic sensor using surface plasmon resonance for clinical diagnosis of fibrinogen.

Nguyen TT, Bea SO, Kim DM, Yoon WJ, Park JW, An SS, Ju H - Int J Nanomedicine (2015)

Bottom Line: On the coated HP layer, immunoglobulin G was then immobilized for specific capturing of Fbg.We demonstrated a real-time quantitative detection of Fbg concentrations with limit of detection of ~10 ng/mL.The fact that the HP layer could be removed by imidazole with acid also permitted us to demonstrate the regeneration of the outermost metal surface of the sensor head for the sensor reusability.

View Article: PubMed Central - PubMed

Affiliation: Department of Bionano Technology, College of Bionano Technology, Gachon University, Seongnam, South Korea.

ABSTRACT

Purpose: We present the regenerative label-free fiber optical biosensor that exploits surface plasmon resonance for quantitative detection of fibrinogen (Fbg) extracted from human blood plasma.

Materials and methods: The sensor head was made up of a multimode optical fiber with its polymer cladding replaced by metal composite of nanometer thickness made of silver, aluminum, and nickel. The Ni layer coated allowed a direct immobilization of histidine-tagged peptide (HP) on its metal surface without an additional cross-linker in between. On the coated HP layer, immunoglobulin G was then immobilized for specific capturing of Fbg.

Results: We demonstrated a real-time quantitative detection of Fbg concentrations with limit of detection of ~10 ng/mL. The fact that the HP layer could be removed by imidazole with acid also permitted us to demonstrate the regeneration of the outermost metal surface of the sensor head for the sensor reusability.

Conclusion: The sensor detection limit was estimated to be ~10 pM, which was believed to be sensitive enough for detecting Fbg during the clinical diagnosis of cardiovascular diseases, myocardial infarction, strokes, and Alzheimer's diseases.

No MeSH data available.


Related in: MedlinePlus

Procedures for regenerative sensing.Notes: (1): HP immobilization; (2): association of IgG with HP; (3): passivation of surface with a blocking solution; (4): Fbg adsorption to IgG; (5): removing HP by imidazole; (6): removing imidazole by acetic acid and PBST; and (7): regenerated metal surface.Abbreviations: HP, histidine-tagged peptide; IgG, immunoglobulin G (fibrinogen antibody); Fbg, fibrinogen; PBST, phosphate-buffered saline with Tween 20.
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f2-ijn-10-155: Procedures for regenerative sensing.Notes: (1): HP immobilization; (2): association of IgG with HP; (3): passivation of surface with a blocking solution; (4): Fbg adsorption to IgG; (5): removing HP by imidazole; (6): removing imidazole by acetic acid and PBST; and (7): regenerated metal surface.Abbreviations: HP, histidine-tagged peptide; IgG, immunoglobulin G (fibrinogen antibody); Fbg, fibrinogen; PBST, phosphate-buffered saline with Tween 20.

Mentions: Figure 2 schematically illustrates the procedures for Fbg sensing, which cover from the sensor surface treatment to the surface regeneration. Firstly, the metal surface in the flow cell was cleaned by flowing PBST. Then, HP (1 μg/mL) was injected for immobilization on the Ni surface (1). The coordinate metal bonding of IM with Ni through nitrogen electrons enabled HP to be immobilized. We used Fbg antibody for stable bonding of Fbg with the surface, even in the presence of surface washout using PBST buffer. This IgG can also be used for selective bonding with Fbg in cases where various other kinds of proteins are present together, which was not our case. We injected Fbg antibody, IgG (0.375 μg/mL concentration, enzyme-linked immunosorbent assay dilution procedure 4,000 times) into the flow cell for IgG immobilization on HPs through peptide–peptide interaction (2). To prevent the nonspecific binding of Fbg molecules to sites other than IgG, the sensor surface was passivated by B (0.4%, volume-to-volume ratio) (3) before immobilization of Fbg on the IgG (4). Note that injection of each layer of HP, IgG, B, and Fbg was followed by respective incubation of ~30-minute duration. Again, a PBST solution was injected to wash away weakly bound molecules after each incubation. For the regeneration of the Ni surface, IM (20 mM) was injected to eliminate HP (5), and the final regeneration of the Ni surface (7) was performed with 1 M ACT and PBST (6).


A regenerative label-free fiber optic sensor using surface plasmon resonance for clinical diagnosis of fibrinogen.

Nguyen TT, Bea SO, Kim DM, Yoon WJ, Park JW, An SS, Ju H - Int J Nanomedicine (2015)

Procedures for regenerative sensing.Notes: (1): HP immobilization; (2): association of IgG with HP; (3): passivation of surface with a blocking solution; (4): Fbg adsorption to IgG; (5): removing HP by imidazole; (6): removing imidazole by acetic acid and PBST; and (7): regenerated metal surface.Abbreviations: HP, histidine-tagged peptide; IgG, immunoglobulin G (fibrinogen antibody); Fbg, fibrinogen; PBST, phosphate-buffered saline with Tween 20.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4556302&req=5

f2-ijn-10-155: Procedures for regenerative sensing.Notes: (1): HP immobilization; (2): association of IgG with HP; (3): passivation of surface with a blocking solution; (4): Fbg adsorption to IgG; (5): removing HP by imidazole; (6): removing imidazole by acetic acid and PBST; and (7): regenerated metal surface.Abbreviations: HP, histidine-tagged peptide; IgG, immunoglobulin G (fibrinogen antibody); Fbg, fibrinogen; PBST, phosphate-buffered saline with Tween 20.
Mentions: Figure 2 schematically illustrates the procedures for Fbg sensing, which cover from the sensor surface treatment to the surface regeneration. Firstly, the metal surface in the flow cell was cleaned by flowing PBST. Then, HP (1 μg/mL) was injected for immobilization on the Ni surface (1). The coordinate metal bonding of IM with Ni through nitrogen electrons enabled HP to be immobilized. We used Fbg antibody for stable bonding of Fbg with the surface, even in the presence of surface washout using PBST buffer. This IgG can also be used for selective bonding with Fbg in cases where various other kinds of proteins are present together, which was not our case. We injected Fbg antibody, IgG (0.375 μg/mL concentration, enzyme-linked immunosorbent assay dilution procedure 4,000 times) into the flow cell for IgG immobilization on HPs through peptide–peptide interaction (2). To prevent the nonspecific binding of Fbg molecules to sites other than IgG, the sensor surface was passivated by B (0.4%, volume-to-volume ratio) (3) before immobilization of Fbg on the IgG (4). Note that injection of each layer of HP, IgG, B, and Fbg was followed by respective incubation of ~30-minute duration. Again, a PBST solution was injected to wash away weakly bound molecules after each incubation. For the regeneration of the Ni surface, IM (20 mM) was injected to eliminate HP (5), and the final regeneration of the Ni surface (7) was performed with 1 M ACT and PBST (6).

Bottom Line: On the coated HP layer, immunoglobulin G was then immobilized for specific capturing of Fbg.We demonstrated a real-time quantitative detection of Fbg concentrations with limit of detection of ~10 ng/mL.The fact that the HP layer could be removed by imidazole with acid also permitted us to demonstrate the regeneration of the outermost metal surface of the sensor head for the sensor reusability.

View Article: PubMed Central - PubMed

Affiliation: Department of Bionano Technology, College of Bionano Technology, Gachon University, Seongnam, South Korea.

ABSTRACT

Purpose: We present the regenerative label-free fiber optical biosensor that exploits surface plasmon resonance for quantitative detection of fibrinogen (Fbg) extracted from human blood plasma.

Materials and methods: The sensor head was made up of a multimode optical fiber with its polymer cladding replaced by metal composite of nanometer thickness made of silver, aluminum, and nickel. The Ni layer coated allowed a direct immobilization of histidine-tagged peptide (HP) on its metal surface without an additional cross-linker in between. On the coated HP layer, immunoglobulin G was then immobilized for specific capturing of Fbg.

Results: We demonstrated a real-time quantitative detection of Fbg concentrations with limit of detection of ~10 ng/mL. The fact that the HP layer could be removed by imidazole with acid also permitted us to demonstrate the regeneration of the outermost metal surface of the sensor head for the sensor reusability.

Conclusion: The sensor detection limit was estimated to be ~10 pM, which was believed to be sensitive enough for detecting Fbg during the clinical diagnosis of cardiovascular diseases, myocardial infarction, strokes, and Alzheimer's diseases.

No MeSH data available.


Related in: MedlinePlus