Description of Procedures and Techniques Associated with Duplex Melting

2d Description of Procedures and Techniques Associated with Duplex Melting 

Calorimetric (DSC) measurements yield thermodynamic properties of duplex melting in these oligonucleotides independent of any assumptions concerning the model of melting, such as a cooperative all-or-none process versus a noncooperative, multiple-stage melting process. Comparison of calorimetric enthalpies with van t Hoff enthalpies obtained either from the manipulation of heat capacity curves outlined in equations (16.19) to (16.22), or from optical or NMR measurements [equations (16.14) to (16.17)] allows conclusions to be drawn concerning the size of the cooperative unit. If the two 

It is sometimes more convenient to analyze the melting process in reverse, that is, the association of monomers to form the duplex. If the process is truly an equilibrium one, then either direction should give an equivalent analysis. We will switch back and forth in our discussion if one direction is more convenient, although most experimental measurements have been of the melting process (rather than the formation reaction), and all thermodynamic properties will be reported for melting. 

The most common type of oligonucleotides studied in the early work of the Breslauer research group involved self-complementary sequences. For example, the sequence d(GCGCGC) can form a duplex in a process according to 

Similarly, the longer, but still self-complementary oligonucleotide d(CGCGAATTCGCG) has been observed to form a duplex via the dimerization/association reaction 

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