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Detection of single amino acid mutation in human breast cancer by disordered plasmonic self-similar chain.

Coluccio ML, Gentile F, Das G, Nicastri A, Perri AM, Candeloro P, Perozziello G, Proietti Zaccaria R, Gongora JS, Alrasheed S, Fratalocchi A, Limongi T, Cuda G, Di Fabrizio E - Sci Adv (2015)

Bottom Line: The sensitivity demonstrated falls in the picomolar (10(-12) M) range.The success of this approach is a result of accurate design and fabrication control.The residual roughness introduced by fabrication was taken into account in optical modeling and was a further contributing factor in plasmon localization, increasing the sensitivity and selectivity of the sensors.

View Article: PubMed Central - PubMed

Affiliation: Bio-Nanotechnology and Engineering for Medicine (BIONEM), Department of Experimental and Clinical Medicine, University of Magna Graecia Viale Europa, Germaneto, Catanzaro 88100, Italy.

ABSTRACT
Control of the architecture and electromagnetic behavior of nanostructures offers the possibility of designing and fabricating sensors that, owing to their intrinsic behavior, provide solutions to new problems in various fields. We show detection of peptides in multicomponent mixtures derived from human samples for early diagnosis of breast cancer. The architecture of sensors is based on a matrix array where pixels constitute a plasmonic device showing a strong electric field enhancement localized in an area of a few square nanometers. The method allows detection of single point mutations in peptides composing the BRCA1 protein. The sensitivity demonstrated falls in the picomolar (10(-12) M) range. The success of this approach is a result of accurate design and fabrication control. The residual roughness introduced by fabrication was taken into account in optical modeling and was a further contributing factor in plasmon localization, increasing the sensitivity and selectivity of the sensors. This methodology developed for breast cancer detection can be considered a general strategy that is applicable to various pathologies and other chemical analytical cases where complex mixtures have to be resolved in their constitutive components.

No MeSH data available.


Related in: MedlinePlus

Fabrication process of silver SSC.(A) After electron beam lithography and surface treatment with 2 M HF, the sample is immersed in HF/AgNO3 aqueous solution, where Ag+ is reduced to silver metal through a redox reaction chain. (B) In nanowells (reduction surface), silver growth follows a spherical symmetry and generates three spheres of appropriate diameter and interdistance. (C) Redox reactions inside a nanowell starting from the silicon surface. (D) SSC architecture and 2D map of electric field. Evidence of external laser polarization along the chain axis. The electric hotspot is localized in the smallest gap. (E to H) SEM images of silver SSCs and possible combinations in monomer, dimer, trimer, and tetramer. Scale bars, 50 nm. PMMA, polymethyl methacrylate.
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Figure 2: Fabrication process of silver SSC.(A) After electron beam lithography and surface treatment with 2 M HF, the sample is immersed in HF/AgNO3 aqueous solution, where Ag+ is reduced to silver metal through a redox reaction chain. (B) In nanowells (reduction surface), silver growth follows a spherical symmetry and generates three spheres of appropriate diameter and interdistance. (C) Redox reactions inside a nanowell starting from the silicon surface. (D) SSC architecture and 2D map of electric field. Evidence of external laser polarization along the chain axis. The electric hotspot is localized in the smallest gap. (E to H) SEM images of silver SSCs and possible combinations in monomer, dimer, trimer, and tetramer. Scale bars, 50 nm. PMMA, polymethyl methacrylate.

Mentions: The proposed device consists of three noble metal nanospheres of appropriate diameter and interdistance relation, as explained by Li et al. (9). The device, firstly proposed by Li et al. (9), shows two spatial regions with plasmonic field localization. In particular, an intense hotspot (Fig. 2D) is localized in the smallest gap (between the smallest sphere and the middle sphere). The footprint area of the hotspot is comparable with the smallest gap. Moreover, the relative position between the nanospheres, calculated by Li et al. (9), was further optimized to maximize the ratio of the electric field in the hotspot to the electric field in the middle gap. However, from the point of view of fabrication, the SSC device presents a challenge because it is necessary to control the smallest nanosphere down to a few tens of nanometers and the smallest gap below the 5-nm range. To meet these fabrication requirements, we combined two techniques: top-down and bottom-up (electron beam lithography and metal electroless deposition) (30–32) (for process details, see Supplementary Materials, section 2). Use of high-resolution electron beam lithography allows the best control of structure definition and positioning, rendering the overall process controllable and reproducible, whereas site-selective and self-assembling silver nanoparticle electroless deposition (31, 33) is used for creating real 3D nanostructures of appropriate size and shape. Figure 2 (A to C) reports the steps of the process and shows representative scanning electron microscopy (SEM) images of SSCs in four different configurations: monomer, dimer, trimer, and tetramer (Fig. 2, E to H).


Detection of single amino acid mutation in human breast cancer by disordered plasmonic self-similar chain.

Coluccio ML, Gentile F, Das G, Nicastri A, Perri AM, Candeloro P, Perozziello G, Proietti Zaccaria R, Gongora JS, Alrasheed S, Fratalocchi A, Limongi T, Cuda G, Di Fabrizio E - Sci Adv (2015)

Fabrication process of silver SSC.(A) After electron beam lithography and surface treatment with 2 M HF, the sample is immersed in HF/AgNO3 aqueous solution, where Ag+ is reduced to silver metal through a redox reaction chain. (B) In nanowells (reduction surface), silver growth follows a spherical symmetry and generates three spheres of appropriate diameter and interdistance. (C) Redox reactions inside a nanowell starting from the silicon surface. (D) SSC architecture and 2D map of electric field. Evidence of external laser polarization along the chain axis. The electric hotspot is localized in the smallest gap. (E to H) SEM images of silver SSCs and possible combinations in monomer, dimer, trimer, and tetramer. Scale bars, 50 nm. PMMA, polymethyl methacrylate.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4643778&req=5

Figure 2: Fabrication process of silver SSC.(A) After electron beam lithography and surface treatment with 2 M HF, the sample is immersed in HF/AgNO3 aqueous solution, where Ag+ is reduced to silver metal through a redox reaction chain. (B) In nanowells (reduction surface), silver growth follows a spherical symmetry and generates three spheres of appropriate diameter and interdistance. (C) Redox reactions inside a nanowell starting from the silicon surface. (D) SSC architecture and 2D map of electric field. Evidence of external laser polarization along the chain axis. The electric hotspot is localized in the smallest gap. (E to H) SEM images of silver SSCs and possible combinations in monomer, dimer, trimer, and tetramer. Scale bars, 50 nm. PMMA, polymethyl methacrylate.
Mentions: The proposed device consists of three noble metal nanospheres of appropriate diameter and interdistance relation, as explained by Li et al. (9). The device, firstly proposed by Li et al. (9), shows two spatial regions with plasmonic field localization. In particular, an intense hotspot (Fig. 2D) is localized in the smallest gap (between the smallest sphere and the middle sphere). The footprint area of the hotspot is comparable with the smallest gap. Moreover, the relative position between the nanospheres, calculated by Li et al. (9), was further optimized to maximize the ratio of the electric field in the hotspot to the electric field in the middle gap. However, from the point of view of fabrication, the SSC device presents a challenge because it is necessary to control the smallest nanosphere down to a few tens of nanometers and the smallest gap below the 5-nm range. To meet these fabrication requirements, we combined two techniques: top-down and bottom-up (electron beam lithography and metal electroless deposition) (30–32) (for process details, see Supplementary Materials, section 2). Use of high-resolution electron beam lithography allows the best control of structure definition and positioning, rendering the overall process controllable and reproducible, whereas site-selective and self-assembling silver nanoparticle electroless deposition (31, 33) is used for creating real 3D nanostructures of appropriate size and shape. Figure 2 (A to C) reports the steps of the process and shows representative scanning electron microscopy (SEM) images of SSCs in four different configurations: monomer, dimer, trimer, and tetramer (Fig. 2, E to H).

Bottom Line: The sensitivity demonstrated falls in the picomolar (10(-12) M) range.The success of this approach is a result of accurate design and fabrication control.The residual roughness introduced by fabrication was taken into account in optical modeling and was a further contributing factor in plasmon localization, increasing the sensitivity and selectivity of the sensors.

View Article: PubMed Central - PubMed

Affiliation: Bio-Nanotechnology and Engineering for Medicine (BIONEM), Department of Experimental and Clinical Medicine, University of Magna Graecia Viale Europa, Germaneto, Catanzaro 88100, Italy.

ABSTRACT
Control of the architecture and electromagnetic behavior of nanostructures offers the possibility of designing and fabricating sensors that, owing to their intrinsic behavior, provide solutions to new problems in various fields. We show detection of peptides in multicomponent mixtures derived from human samples for early diagnosis of breast cancer. The architecture of sensors is based on a matrix array where pixels constitute a plasmonic device showing a strong electric field enhancement localized in an area of a few square nanometers. The method allows detection of single point mutations in peptides composing the BRCA1 protein. The sensitivity demonstrated falls in the picomolar (10(-12) M) range. The success of this approach is a result of accurate design and fabrication control. The residual roughness introduced by fabrication was taken into account in optical modeling and was a further contributing factor in plasmon localization, increasing the sensitivity and selectivity of the sensors. This methodology developed for breast cancer detection can be considered a general strategy that is applicable to various pathologies and other chemical analytical cases where complex mixtures have to be resolved in their constitutive components.

No MeSH data available.


Related in: MedlinePlus