Selecting the wavelength for a real experiment

If one is to use the stopped-flow apparatus in the absorbance mode it is important to know the spectra of the starting reactants and of the final products in order to select the best wavelength at which to collect kinetic data. This wavelength is 

Rgure 2 Baseline measurement to determine the stability of the instrument. Trace a is the average of three individual time courses, with buffer (0.1 m phosphate) in the optical cell, recorded by triggering data capture using the internal trigger. This shows the electronic and lamp noise inherent in the system and demonstrates that this is essentially random noise equivalent to 0.001 A. Trace b shows a similar average captured on mixing buffer with buffer. This demonstrates that mechanical/flow noise is -0.001 over 100 ms. 

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