Table 3. Physicochemical properties of selected nanozymes measured using DLS.

		Effective diameter, nm
Sample	Linker			ζ-potential, mV
		Peak 1	Peak 2
SOD1	-	4.6	-	-2.6
SOD1/PEI-PEG; non-cl*	-	6.1	74.5	-1.5
SOD1/PEI-PEG; cl†	BS3	-	97.4	0.3
SOD1/PEI-PEG; cl	EDC/S-NHS	6.2	63.6	-1.3
SOD1/pLL10-PEG; cl	EDC/S-NHS	6.3	64.2	-2.4
SOD1/pLL10-PEG‡; cl	EDC/S-NHS	5.5	72.0	1.3
SOD1/pLL50-PEG; cl	EDC/S-NHS	5.8	81.0	2.6
catalase (cat)	-	10.0	63	-5.0
cat/PEI-PEG; non-cl	-	12.5	68.4	0.5
cat/PEI-PEG; cl	GA	40.8	644.3	n.d.§
cat/PEI-PEG; cl	BS3	10.6	59.5	-1.2
cat/PEI-PEG; cl	EDC/S-NHS	10.6	52.7	-0.3
cat/pLL10-PEG; non-cl	-	12.0	71.0	-2.4
cat/pLL10-PEG; cl	EDC/S-NHS	12.0	28.2; 504	n.d.§
SOD1-cat/PEI-PE; cl	GA	-	30.0	n.d.§
SOD1-cat/PEI-PEG; cl	BS3	-	91.9	-2.7
SOD1-cat/PEI-PEG; cl	EDC/S-NHS	11.7	91.0	-2.9
SOD1-cat/pLL10-PEG; cl EDC/S-NHS		14.0	135.4	-1.3
All nanozymes were prepared at Z=1 (unless indicated otherwise).
*non-cross-linked, †cross-linked, ‡Z=10; §not determined
Measurement error was typically ≤ 5% of reported values.

Table 3B Diameter of filtered nanozymes measured using DLS
Sample*	Linker	Dz, nm†	PdI‡	ζ, mV§
SOD1	-	5.2 ± 0.1¶	0.1± 0.03	-2.3 ± 0.5
SOD1/pLL50-PEG; non-cl#	-	11.2 ± 0.5	0.2 ± 0.02	6.2 ± 0.5
SOD1/pLL50-PEG; cl**	EDC/S-NHS	9.7 ± 0.1	0.1 ± 0.02	0.6 ± 0.1
catalase (cat)	-	11.5 ± 0.1¶	0.2± 0.01	n.d††
cat/pLL50-PEG; non-cl	-	16.1 ± 0.1	0.2 ± 0.01	n.d.
cat/pLL50-PEG; cl	EDC/S-NHS	19.8 ± 0.3	0.2 ± 0.01	n.d.

SOD1 and catalase formulations were prepared in 10 mM HEPES and 10 mM HEPES-buffered saline (pH 7.4), respectively.

^*All complexes are stoichiometric (Z=1)

^†Z-average diameter (D_z)

^‡polydispersity index (PDI) and

^§ζ-potential. Data are mean ± SD of triplicate measurements.

^¶Theoretical hydrodynamic diameters (Malvern Zetasizer Nano software) are 5.2 nm for SOD1 and 12.5 nm for catalase.

^#non-cross-linked;

^**cross-linked

^††ζ-potential not determined because of high ionic strength.