Table 1. ITC derived thermodynamic parameters for the binding of polyamines to CP DNA^a.

Polyamines	Temperature (K)	Ka (×105 M−1)	N	ΔG o (kcal/mol)	ΔH o (kcal/mol)	TΔS o (kcal/mol)	ΔCp o (cal/mol K)
Spermine	283.15	36.7±0.56	0.271±0.002	−8.500±0.012	−0.175±0.002	8.325±0.010	−35.5±0.03
	288.15	29.6±0.32	0.260±0.001	−8.543±0.009	−0.360±0.003	8.183±0.025
	293.15	18.5±0.10	0.227±0.001	−8.411±0.013	−0.529±0.003	7.882±0.015
Spermidine	283.15	6.94±0.50	0.307±0.001	−7.582±0.014	−0.167±0.001	7.415±0.020	−28.6±0.05
	288.15	5.37±0.38	0.299±0.002	−7.548±0.011	−0.315±0.003	7.233±0.011
	293.15	4.79±0.26	0.276±0.002	−7.602±0.019	−0.453±0.004	7.149±0.014
Putrescine	283.15	2.14±0.16	0.330±0.002	−6.897±0.011	−0.133±0.009	6.764±0.009	−22.9±0.04
	288.15	1.74±0.18	0.329±0.007	−6.918±0.013	−0.236±0.004	6.682±0.013
	293.15	1.18±0.07	0.244±0.002	−6.808±0.007	−0.362±0.008	6.446±0.014
Cadaverine	283.15	1.09±0.12	0.273±0.003	−6.531±0.010	−0.132±0.002	6.399±0.020	−16.1±0.06
	288.15	0.87±0.09	0.213±0.002	−6.506±0.015	−0.228±0.007	6.278±0.011
	293.15	0.69±0.09	0.184±0.003	−6.505±0.009	−0.293±0.012	6.212±0.008

^aAll the data in this table are derived from ITC experiments conducted in 20 mM [Na⁺] citrate-phosphate buffer, pH 7.0 and are average of four determinations, K_a and ΔH ^o values were determined from ITC profiles fitting to Origin 7 software as described in the text. The values of ΔG ^o and TΔS ^o were determined using the equation ΔG ^o = −RTlnK_a, and TΔS ^o = −ΔH ^o−ΔG ^o. All the ITC were fit to a model of single binding sites.