Abstract: An optical sensor and method for use with a visible-light laser excitation beam and a Raman spectroscopy detector, for detecting the presence chemical groups in an analyte applied to the sensor are disclosed. The sensor includes a substrate, a plasmon resonance mirror formed on a sensor surface of the substrate, a plasmon resonance particle layer disposed over the mirror, and an optically transparent dielectric layer about 2-40 nm thick separating the mirror and particle layer. The particle layer is composed of a periodic array of plasmon resonance particles having (i) a coating effective to binding analyte molecules, (ii) substantially uniform particle sizes and shapes in a selected size range between 50-200 nm (ii) a regular periodic particle-to-particle spacing less than the wavelength of the laser excitation beam. The device is capable of detecting analyte with an amplification factor of up to 1012-1014, allowing detection of single analyte molecules.

Abstract: An optical sensor and method for use with a visible-light laser excitation beam and a Raman spectroscopy detector, for detecting the presence chemical groups in an analyte applied to the sensor are disclosed. The sensor includes a substrate, a plasmon resonance mirror formed on a sensor surface of the substrate, a plasmon resonance particle layer disposed over the mirror, and an optically transparent dielectric layer about 2-40 nm thick separating the mirror and particle layer. The particle layer is composed of a periodic array of plasmon resonance particles having (i) a coating effective to binding analyte molecules, (ii) substantially uniform particle sizes and shapes in a selected size range between 50-200 nm (ii) a regular periodic particle-to-particle spacing less than the wavelength of the laser excitation beam. The device is capable of detecting analyte with an amplification factor of up to 1012-1014, allowing detection of single analyte molecules.

Abstract: An optical sensor and method for use with a visible-light laser excitation beam and a Raman spectroscopy detector, for detecting the presence chemical groups in an analyte applied to the sensor are disclosed. The sensor includes a substrate, a plasmon resonance mirror formed on a sensor surface of the substrate, a plasmon resonance particle layer disposed over the mirror, and an optically transparent dielectric layer about 2-40 nm thick separating the mirror and particle layer. The particle layer is composed of a periodic array of plasmon resonance particles having (i) a coating effective to binding analyte molecules, (ii) substantially uniform particle sizes and shapes in a selected size range between 50-200 nm (ii) a regular periodic particle-to-particle spacing less than the wavelength of the laser excitation beam. The device is capable of detecting analyte with an amplification factor of up to 1012-1014, allowing detection of single analyte molecules.

Abstract: An optical sensor and method for use with a visible-light laser excitation beam and a Raman spectroscopy detector, for detecting the presence chemical groups in an analyte applied to the sensor are disclosed. The sensor includes a substrate, a plasmon resonance mirror formed on a sensor surface of the substrate, a plasmon resonance particle layer disposed over the mirror, and an optically transparent dielectric layer about 2-40 nm thick separating the mirror and particle layer. The particle layer is composed of a periodic array of plasmon resonance particles having (i) a coating effective to binding analyte molecules, (ii) substantially uniform particle sizes and shapes in a selected size range between 50-200 nm (ii) a regular periodic particle-to-particle spacing less than the wavelength of the laser excitation beam. The device is capable of detecting analyte with an amplification factor of up to 1012-1014, allowing detection of single analyte molecules.

Abstract: An optical sensor and method for use with a visible-light laser excitation beam and a Raman spectroscopy detector, for detecting the presence chemical groups in an analyte applied to the sensor are disclosed. The sensor includes a substrate, a plasmon resonance mirror formed on a sensor surface of the substrate, a plasmon resonance particle layer disposed over the mirror, and an optically transparent dielectric layer about 2-40 nm thick separating the mirror and particle layer. The particle layer is composed of a periodic array of plasmon resonance particles having (i) a coating effective to binding analyte molecules, (ii) substantially uniform particle sizes and shapes in a selected size range between 50-200 nm (ii) a regular periodic particle-to-particle spacing less than the wavelength of the laser excitation beam. The device is capable of detecting analyte with an amplification factor of up to 1012-1014, allowing detection of single analyte molecules.

Abstract: An optical sensor and method for use with a visible-light laser excitation beam and a Raman spectroscopy detector, for detecting the presence chemical groups in an analyte applied to the sensor are disclosed. The sensor includes a substrate, a plasmon resonance mirror formed on a sensor surface of the substrate, a plasmon resonance particle layer disposed over the mirror, and an optically transparent dielectric layer about 2-40 nm thick separating the mirror and particle layer. The particle layer is composed of a periodic array of plasmon resonance particles having (i) a coating effective to binding analyte molecules, (ii) substantially uniform particle sizes and shapes in a selected size range between 50-200 nm (ii) a regular periodic particle-to-particle spacing less than the wavelength of the laser excitation beam. The device is capable of detecting analyte with an amplification factor of up to 1012-1014, allowing detection of single analyte molecules.

Abstract: Apparatus and method for examining the identity of chemical groups in a sample are disclosed. The apparatus has a substrate having a plasmon resonant surface on which the sample is supported, a source of a beam of light, and a lens assembly having a tip region and a nanolens composed of one or more plasmon resonance particles (PRPs) on the tip region. The PRPs are arranged to produce near-field electromagnetic gap modes in a space between the nanolens and a confronting detection region on the substrate surface when the gap between the nanolens and substrate is 30 nm or less. A focusing mechanism in the apparatus operates to move the lens assembly toward and away from the substrate surface, with a gap of less than 30 nm, to produce electromagnetic gap modes that enhance the Raman spectroscopy signals produced by the sample in the detection region.

Abstract: An optical sensor and method for use with a visible-light laser excitation beam and a Raman spectroscopy detector, for detecting the presence chemical groups in an analyte applied to the sensor are disclosed. The sensor includes a substrate, a plasmon resonance mirror formed on a sensor surface of the substrate, a plasmon resonance particle layer disposed over the mirror, and an optically transparent dielectric layer about 2-40 nm thick separating the mirror and particle layer. The particle layer is composed of a periodic array of plasmon resonance particles having (i) a coating effective to binding analyte molecules, (ii) substantially uniform particle sizes and shapes in a selected size range between 50-200 nm (ii) a regular periodic particle-to-particle spacing less than the wavelength of the laser excitation beam. The device is capable of detecting analyte with an amplification factor of up to 1012-1014, allowing detection of single analyte molecules.

Abstract: Apparatus and method for examining the identity of chemical groups in a sample are disclosed. The apparatus has a substrate having a plasmon resonant surface on which the sample is supported, a source of a beam of light, and a lens assembly having a tip region and a nanolens composed of one or more plasmon resonance particles (PRPs) on the tip region. The PRPs are arranged to produce near-field electromagnetic gap modes in a space between the nanolens and a confronting detection region on the substrate surface when the gap between the nanolens and substrate is 30 nm or less. A focusing mechanism in the apparatus operates to move the lens assembly toward and away from the substrate surface, with a gap of less than 30 nm, to produce electromagnetic gap modes that enhance the Raman spectroscopy signals produced by the sample in the detection region. The apparatus and method are useful, for example, in identifying successive bases in a single DNA strand, for direct DNA sequencing.

Abstract: The invention generally relates to a new gene probe biosensor employing near field surface enhanced Raman scattering (NFSERS) for direct spectroscopic detection of hybridized molecules (such as hybridized DNA) without the need for labels, and the invention also relates to methods for using the biosensor.

Abstract: The invention generally relates to a new gene probe biosensor employing near field surface enhanced Raman scattering (NFSERS) for direct spectroscopic detection of hybridized molecules (such as hybridized DNA) without the need for labels, and the invention also relates to methods for using the biosensor.

Abstract: The invention generally relates to a new gene probe biosensor employing near field surface enhanced Raman scattering (NFSERS) for direct spectroscopic detection of hybridized molecules (such as hybridized DNA) without the need for labels, and the invention also relates to methods for using the biosensor.