A hybrid Attenuated Total Reflection fiber optic probe device having a radiation source; a detecting system; a core-only solid optical fiber probe tip having an input end and an output end; an input hollow fiber waveguide configured for association with the radiation source at a first end and interconnection with the input end of the core-only solid optical fiber probe tip at a second end; an output hollow fiber waveguide configured for interconnection with the output end of the core-only solid optical fiber probe tip at a first end and association with the detection system at a second end; an inwardly tapered solid fiber input radiation collector element configured at a tapered end for interconnection with the second end of the output hollow fiber waveguide so as to receive radiation from the radiation source; wherein an outside diameter of the core-only solid optical fiber probe tip and an inside diameter of each one of the input hollow fiber waveguide and the output hollow fiber waveguide is such that the interconnection between each one of the input hollow fiber waveguide and the output hollow fiber waveguide and the core-only solid optical fiber probe tip is by means of inserting the input end of the core-only solid optical fiber probe tip into the second end of the input hollow fiber waveguide and inserting the output end of the core-only solid optical fiber probe tip into the first end of the output hollow fiber waveguide, such that the core-only solid optical fiber probe tip is held in the input and output hollow fiber waveguides by means of friction, and wherein an outside diameter of a portion of the inwardly tapered solid fiber input radiation collector element and an inside diameter of the second end of the output hollow fiber waveguide is such that the tapered end of the inwardly tapered solid fiber input radiation collector element is held in the end of the second end of the output hollow fiber waveguide by means of friction.

System and methods for sensing fluid characteristics of peritoneal dialysate infused into and removed from a patient during treatment are provided. The systems and methods can use an optical sensor including a transmitter light source operable to emit light through a fluid flow path and an optical receiver operable to receive at least a portion of the light emitted by the transmitter light source.

Disclosed is an optical sensor device for detecting a chemical analyte including a light source configured to generate probe light having a first wavelength spectrum, an optical fiber sensor probe including a mechanically processed optical fiber segment which is chemically functionalized to include a sensing material formed on exterior of the fiber segment, the optical fiber sensor probe coupled to receive and guide the generated probe light inside the optical fiber sensor probe while allowing optical evanescent coupling between probe light guided inside the optical fiber sensor probe and the sensing material, and a detector coupled to the optical fiber sensor probe to optically detect the guided probe light to obtain information on a material property of the sensing material.

We describe a method of selectively detecting the presence of an analyte, the method comprising: providing at least one waveguide, the waveguide having a core comprising porous material; absorbing an analyte sample into said porous material of said core such that said analyte sample is held within pores of said core; waveguiding radiation along said at least one waveguide to an output to provide output radiation; measuring one or more spectral features of said output radiation due to absorption or scattering of said waveguided radiation by said absorbed analyte sample; selectively identifying the presence of a target analyte in said analyte sample from said one or more spectral features. In embodiments spectral features are measured for multiple different waveguide core regions having different physical/chemical properties modified to provide additional selectivity to the target analyte(s), and these measurements combined to identify the target analyte.

We describe a method of selectively detecting the presence of an analyte, the method comprising: providing at least one waveguide, the waveguide having a core comprising porous material; absorbing an analyte sample into said porous material of said core such that said analyte sample is held within pores of said core; waveguiding radiation along said at least one waveguide to an output to provide output radiation; measuring one or more spectral features of said output radiation due to absorption or scattering of said waveguided radiation by said absorbed analyte sample; selectively identifying the presence of a target analyte in said analyte sample from said one or more spectral features. In embodiments spectral features are measured for multiple different waveguide core regions having different physical/chemical properties modified to provide additional selectivity to the target analyte(s), and these measurements combined to identify the target analyte.

We describe a method of selectively detecting the presence of an analyte. The method comprises providing a waveguide with a core comprising porous material; absorbing an analyte sample into the porous material of the core such that the analyte sample is held within pores of the core; waveguiding radiation along the waveguide to an output; measuring spectral features of the output radiation due to absorption or scattering of said waveguided radiation by the absorbed analyte sample; and selectively identifying the presence of a target analyte in the sample from the spectral features. In embodiments spectral features are measured for multiple different waveguide core regions having different physical/chemical properties modified to provide additional selectivity to the target analyte(s), and these measurements are combined to identify the target analyte.