Method and apparatus for quantifying solutions comprised of multiple analytes

A system for the determination of the concentration of at least one target analyte present in a gaseous or liquid sample using Raman anti-Stokes radiation spectroscopy said system comprising:

• (a) a laser pump light source emitting light in the ultraviolet to near infrared spectral region;
• (b) an inlet for said laser light into a hollow core photonic band gap (HCPBG) fiber, said HCPBG fiber operating in a fundamental mode or a limited number of modes;
• (c) a bi-directional pump configured, in a first pumping direction, to introduce at least one reference calibrant into the core of said HCPBG fiber via an inlet port in fluid communication with the core, and, in a second pumping direction, to introduce the sample containing the at least one target analyte into the core of said HCPBG fiber via an additional port;
• (d) a spectral analysis system comprising at least one filter and/or dispersive element and a detector array or CCD including means for detecting and quantifying Raman anti-Stokes spectrum and/or spectral peaks emitted by the reference calibrant to establish a baseline response and account for cross sensitivities or spectral peak overlaps in the sample when illuminated by said light source;
• (e) means for optically coupling components (a) and (d) to the core of said HCPBG fiber.

An analyzer system for determining the identity and concentration of at least one target analyte present in a gaseous or liquid sample utilizing the Raman optical scattering effect, said analyzer system comprising:

• (i) an excitation light source coupled into an excitation fiber through an optical system, the excitation light source emitting light having a wavelength in the ultraviolet to near infrared spectral region;
• (ii) a hollow core photonic band-gap (HCPBG) fiber optically connected to the excitation fiber, said HCPBG fiber including:
• a first inlet in fluid communication with the hollow core of the HCPBG fiber and a conduit for selectively introducing sample containing the target analyte and/or at least one reference calibrant corresponding to an analyte in the sample into the hollow core of the HCPBG fiber;
• and
• an outlet for expelling the sample containing the target analyte and/or the reference calibrant from the hollow core of the HCPBG fiber;
• (iii) an exit fiber optically connected to the HCPBG fiber;
• and
• (iv) a detection system coupled to the exit fiber and comprising a dichroic beam splitter for receiving the excitation light, the Raman Stokes light, and the Raman anti-Stokes light from the exit fiber and for splitting the Raman anti-Stokes light to a detector array or CCD associated with the detection system,
• wherein the detection system is configured to derive the Raman anti-Stokes spectral peaks and/or spectra of the target analyte from the Raman anti-Stokes light received at the detector array or CCD to establish a baseline response and account for cross sensitivities or spectral peak overlaps in the sample.