. Author manuscript; available in PMC: 2014 Sep 18.

Published in final edited form as: J Am Chem Soc. 2013 Jul 16;135(30):11299–11308. doi: 10.1021/ja4047872

Table 1.

Summary of properties of ELPs: composition and corresponding LCST.

	A-40^b	A₈V₂-40^b	A₅V₅-40	A₂V₈-40	V-40
Composition^a	100% A	80% A / 20% V	50% A / 50% V	20% A / 80% V	100% V
T_c,EPR/°C^c	-	70 ± 1	52 ± 1	44 ± 1	38 ± 1
T_{c,Turbidimetry}/°C	69.2	60.4	49.7	40.8	34.4
	A-80	A₈V₂-80	A₅V₅-80	A₂V₈-80	V-80
Composition	100% A	80% A / 20% V	50% A / 50% V	20% A / 80% V	100% V
T_c,EPR/°C	70 ± 1	54 ± 1	36 ± 1	34 ± 1	32 ± 1
T_{c,Turbidimetry}/°C	66.4	52.8	41.1	32.9	28.1

“Composition” denotes the composition of the guest residues Xaa, in the otherwise always identical Val-Pro-Gly-Xaa-Gly sequence.

The discrepancy between T_c,EPR and T_c for ELP A/ A₈V₂-40 is a consequence of large amounts of residual water in the ELP aggregates above the LCST, which screen the hydrophobic interaction between 16-DSA and the ELP aggregates. Such interactions between 16-DSA and A-y ELPs can only be observed at temperatures significantly above the LCST, since increased dehydration of the ELPs is needed for significant interaction between 16-DSA and the aggregates.

Note that T_c,EPR denotes the onset of observable interaction between the ELP and 16-DSA, while T_c denotes the cloud point of the solution (i.e., the temperature of the inflection point in a turbidity profile).