Sam N. Pennington

Construction and Operation of a Benchtop Four-Element Instrument for Analytical Microcalorimetry

SUMMARY A benchtop microcalorimeter has been designed, constructed, and applied to analytic determinations which include both inorganic and enzymic reactions. The exceptional stability and short equilibration time of the calorimeter have made possible its use for multiple analyses with facility. Ease of operation, nearly universal applicability, and readout in thermodynamic values, as well as the simultaneous availability of “kinetic” data make this instrument useful in analytic chemistry. The measurement of reaction ΔH provided directly by the instrument is widely applicable in analysis because enthalpy changes during the course of chemical reaction are universal with only most occasional exception.

Analytical Application of Microcalorimetry

Abstract A “bench top” microcalorimeter has been designed and constructed. This instrument, and a more conventional microcalorimeter previously described, have been applied to several analytical determinations including both inorganic and enzymatic reactions. Because of the stability, yet rapid equilibration time of the bench top calorimeter, multiple analyses may be performed. The ease of operation, nearly universal applicability, and the possibility of obtaining thermodynamic as well as kinetic data simultaneously, make this technique extremely useful.

Microcalorimetric determination of metal cations

SummarySilver and lead, respectively, are determined in a microcalorimeter by measuring the effect of the cation concentration upon an enzyme catalyzed reaction. The reduction in heat of the glucose oxidase catalyzed reaction in presence of Ag+ and Pb2+ is confirmed.ZusammenfassungSilber bzw. Blei kann man mit einem Mikrokalorimeter bestimmen, indem die Wirkung der Konzentration des Kations auf eine enzymatische Reaktion gemessen wird. Die Herabsetzung der Wärmetönung der durch Glukoseoxydase katalysierten Reaktion in Gegenwart von Ag+ bzw. Pb2+ wurde bestätigt.

A note on supporting matrices for adenyl cyclase.

Abstract Five insoluble matrices are described for the solid-support of solubilized cardiac adenyl cyclase. Straight forward chemistries are proposed for the reactions involved and for at least one matrix, an apparent purification of the cyclase activity was observed.