. 2013 Jul 1;10:26. doi: 10.1186/1743-8977-10-26

Table 1.

Grafting amount and size of SNP after different steps of synthesis: plain SNP (SNP) to amine-modified SNP (aSNP), to alkyne-modified (aaSNP) and to final PEG-coated SNP

Sample	Weight Loss (%)^a	Grafting amount (t, mmol/g)^a	Grafting density (group/nm²)^a	Size (nm)^b
plain SNP	1.7^g	1.9^h	8.1^h	30^c
aSNP	3.6	0.63	2.7	103^d
aaSNP	2.4	0.29	1.2	126^e
PEG-coated SNP	3.6	0.15	0.7	90^c

^aWeight loss, grafting amount and density were calculated for each modification step, not for total modification. ^bSize were measured by dynamic light scattering as mono-distribution after sonication for 30-60 min. ^cSize was measured in H₂O. ^dSize was measured in dimethylformamide triethylamine (DMF-TEA) (3:1). ^eSize was measured in DMF. ^gWeight loss of water from surface of bare silica particle. ^h Grafting amount and density of Si-OH available for modification on the surface calculated from water loss.