Resumen
Optical method of detecting a target molecule by amplifying the interference response by refractive index and dispersion. Optical method of detecting at least one target molecule (OM) contained in a sample at a certain concentration, comprising: a) contacting, in a liquid medium, the sample containing the MO with a solution containing nanoparticles (NPs)) whose surface has been upholstered or functionalized with at least one type of bioreceptor (BR) specific to the target molecule to be detected (NP-BR), so that these BRs specifically recognize said OM, and therefore conjugates of the NP are formed -BRs with MOs (NP-BR-MOs); b) separating the nanoparticle conjugates (NP-BR-MOs and/or NP-BRs) formed in the previous step; c) contacting the conjugates of said nanoparticles (NP-BR-MOs and/or NP-BRs) with a sensor surface of an optical transducer that works by reflection and/or transmission, whose response is based on optical interference and where This sensor surface will be functionalized by immobilizing on its surface: i) the target molecule (MO), or ii) at least one specific bioreceptor, which may be of the same type (BR) or of another type (BR1) of the target molecule; and c) determining the optical reading on the sensor surface by the change in the interference response of the optical transducer caused by the change in the real part of the refractive index caused by said NP conjugates recognized on the sensor surface, and/or by the intensity change in said interference response caused by the intensity variation caused either by the dispersion or by the variation in the complex part of the refractive index of the mentioned NPs conjugates, or by a combination of both effects. (Machine-translation by Google Translate, not legally binding)
Reivindicaciones
1. An optical method for the detection of at least one target molecule in a sample, the method comprising: a. Measuring the interference response of an optical sensor or interferometric transducer with its biofunctionalized sensor surface (figure 1A) with: i. the target molecule (TM) to be analyzed comes from a sample selected from the group consisting of a biological sample, a clinical sample, an agri-food sample and water ii. Or at least one specific bioreceptor (BR or BR1) of the target molecule; b. Putting in contact, in a liquid medium, a sample to be analyzed with functionalized nanoparticles (NPs) with at least one specific bioreceptor (NP-BR) of the target molecule (TM), forming a conjugate (NP-BR-TM) with the functionalized nanoparticles and the target molecules present in the sample; c. Separating NP-BR conjugates from the sample and, provided the sample comprises the target molecule, NP-BR-TM conjugates formed in the mixture obtained after step b); d. Putting in contact said NP-BR, and if applicable, the NP-BR-TM conjugates obtained in step b) with said biofunctionalized sensor surface of the interferometric transducer; and e. Determining the optical reading, measuring the variation of the actual part of the refractive index and/or the variation of intensity caused by the scattering or variation in the complex part of the refractive index of the NP-BR conjugates, and if applicable, the NP-BR-TM conjugates, or a combination of the foregoing, on the sensor surface of the interferometric transducer. 2. The optical detection method according to claim 1, wherein the target molecule is an IgE allergy specific antibody specific to an allergenic molecule (AM). 3. The optical detection method according to claim 2, wherein the BR1 is the allergenic molecule (AM) specific for an allergy specific antibody and the sensor surface is functionalized with said allergenic molecule (AM). 4. The optical detection method according to any one of claims 1 to 3, wherein the clinical sample to be analyzed is selected from the group consisting of blood, serum, plasma, saliva, tears and urine. 5. The optical detection method according to any one of claims 1 to 4, wherein the sample to be analyzed is a clinical sample and the target molecule is a biomarker for in vitro diagnosis. 6. The optical detection method of claim 5, wherein the biomarker is selected from the group consisting of proteins, hormones, immunoglobulins, toxins, or any molecule that is recognized by immunological processes. 7. The optical detection method according to any one of claims 1 to 6, wherein steps a) and c) take place at a temperature between 0 and 40°C, the temperature conditions of these steps being equal or different from each other. 8. The optical detection method according to any one of claims 1 to 7, wherein step b) of separation takes place by a technique selected from the group consisting of centrifuging, electric field separation, magnetic field separation, and a combination of the foregoing. 9. The optical detection method according to any one of claims 1 to 8, wherein the nanoparticles are selected from the group consisting of silica, alumina, silicon nitride, silicon, dielectric materials, metal oxides, magnetic materials, gold, aluminum, silver, and metallic materials. 10. The optical detection method according to any one of claims 1 to 9, wherein the optical sensor is a Fabry-Perot interferometer, and the functionalized nanoparticles (NP-BR) comprise spherical silica nanoparticles with a diameter between 50 nm and 100 nm. 11. The optical detection method according to claim 10, wherein the concentration of NPs is between 10<8> to 10<12> NPs/µL. 12. The optical detection method according to any one of claims 1 to 9, wherein the optical sensor is a Fabry-Perot interferometer, and the functionalized nanoparticles (NP-BR) comprise gold nanoparticles with a diameter of between 20-70 nm. 13. The optical detection method according to claim 12, wherein the concentration of NPs is between 10<8> to 10<11> NPs/mL.
