Abstract:
We describe a system/method for predicting the outcome of a medical procedure on a patient. The system/method uses using complement cascade data representing levels of a set of complement cascade markers in the patient at a succession of peri-operative time intervals, determining deviations from a model of the response to provide a pre-symptomatic prediction of the outcome. In embodiments the complement cascade pathways include the lytic pathway and at least one of the lectin pathway, the classical pathway and the alternative pathway, and the biomarkers include at least C3. The system may include an electroluminescence or plasmon-resonance multianalyte detector to analyse a blood sample from the patient.
Abstract:
This invention is generally concerned with methods and apparatus for optical monitoring of fluid level and quality, in particular by means of evanescent wave techniques such as cavity ring-down spectroscopy. We describe a fuel monitoring system, comprising: an evanescent wave fuel sensor for monitoring said fuel, the sensor comprising a light source and a transducer for providing an electrical signal in response to light from said light source, and having a light path between said light source and said transducer including an evanescent wave sensing region; and a processor coupled to said fuel sensor, for converting said electrical signal from said transducer into a signal characterising said monitored fuel; and an output coupled to said processor, for outputting a signal responsive to said fuel characterising signal. We further describe apparatus for jointly determining depth of fluid in a tank and characterising the fluid according to depth, and a fluid storage tank having a three dimensional structure for containing fluid, and a three-dimensional array of fibre-optic sensors integrated into said tank structure.
Abstract:
This invention is generally concerned with sensing apparatus and methods, more particularly apparatus and methods for sensing techniques based upon cavity ring-down spectroscopy (CRDS). An evanescent wave cavity-based optical sensor is described. The sensor comprises an optical cavity formed by a pair of highly reflective surfaces (108, 110) such that light within said cavity makes a plurality of passes between said surfaces, an optical path between said surfaces including a reflection from a totally internally reflecting (112) surface, said reflection from said reflection from said surface generating an evanescent wave to providing a sensing function; a light source (102) to inject light into said cavity; and a detector (114) to detect a light level within said cavity; whereby absorption of said evanescent wave is detectable using said detector to provide said sensing function; wherein said light source comprises a continuous wave light source; and wherein said light source has a power and bandwidth sufficient to couple energy into at least two modes of oscillation of said cavity to overcome losses within the cavity and excite at least two modes of oscillation of said cavity.
Abstract:
This invention relates to photonic biosensor arrays in particular employing plasmon resonance based sensing, and to methods and apparatus for reading such arrays. A biosensor array for plasmon resonance-based sensing of a plurality of different biological targets simultaneously, the array comprising a transparent substrate having a surface bearing a plurality of assay spots for plasmon resonance sensing, each of said assay spots comprising a discrete metallic island, a said metallic island comprising a plurality of metallic nanoparticles to which are attached functionalising molecules for binding to a said biological target, different said islands bearing different said functionalising molecules for binding to different ones of said biological targets, and wherein total internal reflection of light at said surface at a wavelength at or near a said plasmon resonance results in scattering of said light away from said surface, said scattering being modulated by said binding of said biological targets.
Abstract:
This invention is generally concerned with sensing techniques based upon evanescent-wave cavity ring-down spectroscopy (CRDS), with particular reference to functionalising a sensing surface with the aim of increasing specificity and/or sensitivity. An evanescent wave cavity-based optical sensor is described. The sensor comprises an optical cavity formed by a pair of highly reflective surfaces such that light within said cavity makes a plurality of passes between said surfaces, an optical path between said surfaces including a reflection from a totally internally reflecting (TIR) surface, said reflection from said TIR surface generating an evanescent wave to provide a sensing function; a light source to inject light into said cavity; and a detector to detect a light level within said cavity ; and wherein said TIR surface is provided with a functionalising material over at least part of said TIR surface such that said evanescent wave interacts with said material ; whereby an interaction between said funtionalising material and a target to be sensed is detectable as a change in absorption of said evanescent wave. Preferably the TIR surface has substantially no features with a dimension perpendicular to the surface of greater than 3µm, more preferably 1µm.
Abstract:
This invention is generally concerned with apparatus and methods for sensing based upon evanescent-wave cavity ring-down spectroscopy (CRDS), in particular time-resolved and multiplexed sensing techniques. We describe an evanescent wave cavity-based optical sensor, the sensor comprising: an optical cavity formed by a pair of highly reflective surfaces such that light within said cavity makes a plurality of passes between said surfaces, an optical path between said surfaces including a reflection from a totally internally reflecting (TIR) surface, said reflection from said TIR surface generating an evanescent wave to provide a sensing function; a light source to inject a pulse of light into said cavity; a detector to detect decaying oscillations of said light pulse within said cavity; and a signal processor coupled to said detector and configured to provide a time-resolved output responsive to a light level within said cavity and having a time-resolution corresponding to a set of said light pulse oscillations, whereby said sensing function operates at substantially said time-resolution. We further describe a system where one or more TIR surfaces are provided with at least two functionalising materials responsive at different wavelengths such that an interaction between a said functionalising material and one or more targets to be sensed is detectable as a change in absorption of a said evanescent wave at a said wavelength.
Abstract:
This invention is generally concerned with apparatus and methods for monitoring fluids, in particular critical fluids such as lubricants, based upon evanescent wave techniques. A sensor module, in particular for use with attenuated total internal (ATIR) reflection apparatus for optically determining the condition of a fluid, the sensor module comprising: an evanescent wave sensor; a module housing for said sensor; and an optical connector for connecting said sensor to said ATIR apparatus. Preferably the sensor comprises a tapered optical fibre with a high reflectivity mirror at one or both ends. Also attenuated total internal reflection (TIR) apparatus for the sensor.
Abstract:
A functionalised gold nanoparticle conjugate comprising a gold nanoparticle linked to at least one antigen, in particular the F1 protein of Yersinia pestis , via a thiol- carboxylic acid linker molecule, such as mercaptodecanoic acid. The reactants are coupled together in the presence of a non-ionic detergent to aid stabilisation of the nanoparticle conjugate to enable its purification and further manipulation.
Abstract:
This invention relates to photonic biosensor arrays in particular employing plasmon resonance based sensing, and to methods and apparatus for reading such arrays. A biosensor array for plasmon resonance-based sensing of a plurality of different biological targets simultaneously, the array comprising a transparent substrate having a surface bearing a plurality of assay spots for plasmon resonance sensing, each of said assay spots comprising a discrete metallic island, a said metallic island comprising a plurality of metallic nanoparticles to which are attached functionalising molecules for binding to a said biological target, different said islands bearing different said functionalising molecules for binding to different ones of said biological targets, and wherein total internal reflection of light at said surface at a wavelength at or near a said plasmon resonance results in scattering of said light away from said surface, said scattering being modulated by said binding of said biological targets.
Abstract:
This invention relates to a method for the fabrication of photonic biosensor arrays and applications of arrays produced by the method in the biomedical field. A method for the fabrication of a biosensor array for plasmon resonance-based sensing of a plurality of different biological targets simultaneously, the method comprising: (i) providing a transparent substrate; ii) providing seed metallic nanoparticles in the form of a colloid; (iii) depositing said colloid as discrete metallic islands on the transparent substrate, each of said metallic islands comprising a plurality of metallic nanoparticles; (iv) washing the substrate in order to remove unadhered material; (v) developing the substrate in a growth solution, which solution comprises a salt of the same metal which is present in the form of discrete metallic islands on the substrate, a reducing agent, a capping agent and optionally a surfactant; (vi) washing the developed substrate; and (vii) functionalising each of said metallic islands with a different functionalising molecule using a common chemical process to attach said different functionalising molecules to said metallic islands.