The present invention is directed to methods and compositions for separating and isolating target molecules. The portable pressure transducer may removably couple with a pneumotach, in the form of an airway adapter, disposed along the respiratory conduit. The selector selects from laser light emitted from the laser through the surface with the anti-reflection film and feeding laser light of a desired wavelength back to the laser through the surface with the anti-reflection film. ; n is 1 or 2; R3 is a substituted or unsubstituted aromatic carbocyclic group; R4 is a hydrogen atom etc.