Table 1.

Table outlining the physical/chemical parameters of SAN NAs

Neuropeptide	Conjugation sitea)	Sizeb) [nm]	PDIb,c)	Charged)	Drug loading
Leu-enkephalin	–COOH	147	0.174	+21 mV	60%
Met-enkephalin	–COOH	130	0.181	+36 mV	61%
Endomorphin-1	–NH2	117	0.079	−0.62 mV	62%
Endomorphin-2	–NH2	103	0.107	−0.14 mV	59%
Leu-enkephalin	–NH2	136	0.079	−58 mV	59%

^a)Detailed structure in the Supporting Information;

^b)polydispersity index;

^c)DLS method;

^d)Zeta potential measurements.