Quantitative characterization of agglomerates and aggregates of pyrogenic and precipitated amorphous silica nanomaterials by transmission electron microscopy

Table 5 Comparison of the characteristics of agglomerates and aggregates of SAS NM

	Mean diameter (nm)^x	Sphericity ^x	Shape factor ^x	% < 100 nm ^x,y
NM-200	31 ± 3 ^a	0,39 ± 0,01 ^a	0,51 ± 0,02 ^a	94 ± 1 ^a
NM-201	43 ± 4 ^a,b	0,4 ± 0,01 ^a	0,56 ± 0,05 ^a	91 ± 2 ^a,b
NM-202	53 ± 9 ^b	0,36 ± 0,01 ^b	0,35 ± 0,01 ^b	87 ± 2 ^b
NM-203	48 ± 4 ^b	0,35 ± 0,02 ^b	0,35 ± 0,02 ^b	88 ± 2 ^b

^x Mean values of medians ± SD are represented for 3 independent analyses.
^y The percentage of particles with a minimal feret diameter smaller than 100 nm is represented.
^{a, b} Different letters indicate significantly different mean values by Kruskal-Wallis One Way Analysis of Variance on Ranks (P < 0,05).

ISSN: 1477-3155