Stopped-flow down to -90°C

The SFM-series of stopped-flow are temperature regulated using a circulating water bath. In their standard configuration, the stopped-flows may be operated from -20°C to +85°C, offering more than a 100 degree temperature range to the user. However, some applications in inorganic chemistry require lower temperatures to slow down the reactions enough to enable the observation of the intermediates and final products optically.

By coupling the SFM-series to a cryostat, the operating temperature limit can be decreased to -90°C allowing the chemical reaction to slow down more than 3000 times. Absorbance spectra are collected at a 400µs sampling rate with a diode array detector to trap the structure of intermediates invisible at ambient temperature.

The reaction between 2,4 dinitrophenyl acetate (DNPA) and sodium methoxide in ethanol and acetone is used to illustrate the benefits of the SFM in this cryogenic condition..

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