Abstract: A preferred embodiment biosensor is a multi-layer micro-porous thin film structure. Pores in a top layer of the micro-porous thin film structure are sized to accept a first molecule of interest. Pores in a second layer of the micro-porous thin film structure are smaller than the pores in the top layer and are sized to accept a second molecule of interest that is smaller than the first molecule of interest. The pores in the second layer are too small to accept the first molecule of interest. The pores in the top layer and the pores in the second layer are sized and arranged such that light reflected from the multi-layer micro-porous thin film structure produces multiple superimposed interference patterns that can be resolved. In preferred embodiments, the multi-layer micro-porous thin film structure is a porous silicon thin film multi-layer structure formed on a silicon substrate, such as a silicon wafer. Specific and nonspecific binding can be detected with biosensors of the invention.

Abstract: A preferred embodiment biosensor is a multi-layer micro-porous thin film structure. Pores in a top layer of the micro-porous thin film structure are sized to accept a first molecule of interest. Pores in a second layer of the micro-porous thin film structure are smaller than the pores in the top layer and are sized to accept a second molecule of interest that is smaller than the first molecule of interest. The pores in the second layer are too small to accept the first molecule of interest. The pores in the top layer and the pores in the second layer are sized and arranged such that light reflected from the multi-layer micro-porous thin film structure produces multiple superimposed interference patterns that can be resolved. In preferred embodiments, the multi-layer micro-porous thin film structure is a porous silicon thin film multi-layer structure formed on a silicon substrate, such as a silicon wafer. Specific and nonspecific binding can be detected with biosensors of the invention.

Abstract: The invention provides an optical sensor for detecting chemical reaction activity, including, e.g., enzyme activity and catalytic or reactive molecule activity. An optical sensor of the invention includes a porous photonic film that produces a predetermined spectral reflectance response. In preferred embodiments, the film has a chemical coating (such as a hydrophobic layer) within its pores with an affinity for the reaction product(s) of the catalytic or otherwise reactive analyte A coating can also act as a protective layer in preferred embodiment. A thin substrate susceptible to reaction by at least one analyte of interest is on the surface of the thin film to block pores of the thin film. A method of detecting chemical reaction activity of the invention exposes the optical sensor to an analyte of interest, such as an enzyme or otherwise catalytic or reactive molecule.

Abstract: The invention provides an optical sensor for detecting chemical reaction activity, including, e.g., enzyme activity and catalytic or reactive molecule activity. An optical sensor of the invention includes a porous photonic film that produces a predetermined spectral reflectance response. In preferred embodiments, the film has a chemical coating (such as a hydrophobic layer) within its pores with an affinity for the reaction product(s) of the catalytic or otherwise reactive analyte A coating can also act as a protective layer in preferred embodiment. A thin substrate susceptible to reaction by at least one analyte of interest is on the surface of the thin film to block pores of the thin film. A method of detecting chemical reaction activity of the invention exposes the optical sensor to an analyte of interest, such as an enzyme or otherwise catalytic or reactive molecule.