Abstract: A method is provided for characterizing analyte-specific affinity agents having affinity for an analyte. The method includes providing a library of candidate affinity agents, providing a surface suitable for adhesion of the library of candidate affinity agents, and exposing the library of candidate affinity agents to the surface to thereby adhere the library of candidate affinity agents to the surface. It also includes providing an analyte, and causing the analyte to contact the surface to thereby expose the library of candidate affinity agents adhered to the surface to the analyte, to cause selected ones of the candidate affinity agents to react with the analyte to form reaction products, and to create an output fluid that comprises the reaction products. In addition, the method includes analyzing the output fluid to characterize the analyte-specific affinity agents associated with the respective reaction products.

Abstract: A method is provided for sensing ammonia in a breath sample. The method comprises conditioning the breath sample so that the conditioned breath sample has a relative humidity greater than a relative humidity corresponding to a first inflection point of a downwardly concave lowest ammonia iso-concentration curve. It also comprises contacting the conditioned breath sample with an interactant that interacts with the ammonia in the conditioned breath sample, wherein the interaction causes a change in an optical characteristic in relation to the amount of the ammonia in the breath sample. It further comprises using the change in the optical characteristic to sense the ammonia in the breath sample. Related apparatuses are also provided.

Abstract: Methods and devices are provided for analyzing acetone in breath. One such method comprises disposing a reactant in a reaction zone within the breath analysis device, wherein the reactant comprises a primary amine disposed on a surface, and wherein the reaction zone has an optical characteristic that is at a reference level. It also comprises pre-storing a liquid nitroprusside solution within the breath analysis device separately from the reactant. The method further comprises using the breath analysis device to cause the breath to contact the reactant in the reaction zone so that the acetone in the breath reacts with the reactant to form a reaction product and, after the reaction product has been formed, using the breath analysis device to cause the nitroprusside solution to contact and react with the reaction product and to facilitate a change in the optical characteristic of the reaction zone relative to the reference level.

Abstract: Methods and devices are provided for analyzing acetone in breath. One such method comprises disposing a reactant in a reaction zone within the breath analysis device, wherein the reactant comprises a primary amine disposed on a surface, and wherein the reaction zone has an optical characteristic that is at a reference level. It also comprises pre-storing a liquid nitroprusside solution within the breath analysis device separately from the reactant. The method further comprises using the breath analysis device to cause the breath to contact the reactant in the reaction zone so that the acetone in the breath reacts with the reactant to form a reaction product and, after the reaction product has been formed, using the breath analysis device to cause the nitroprusside solution to contact and react with the reaction product and to facilitate a change in the optical characteristic of the reaction zone relative to the reference level.

Abstract: A system is provided for sensing an analyte in a breath sample. The system includes a breath bag, a cartridge and a base. The breath bag contains the breath sample. The bag includes a mouthpiece fixedly disposed on the breath bag. The cartridge includes an interactant that reacts with the analyte and generates a change in an optical characteristic relative to a reference. The base includes a flow path, a breath bag receiver for detachably receiving and retaining the mouthpiece of the breath bag in fluid communication with the flow path, and a cartridge receiver that detachably receives and retains the cartridge in the base, such that the base engages the cartridge so that the interactant is in fluid communication with the flow path.