. Author manuscript; available in PMC: 2020 Mar 7.

Published in final edited form as: Nanoscale. 2019 Mar 7;11(10):4531–4545. doi: 10.1039/C8NR07667G

Table 4. Chemical shifts and populations (%) of the silicon Qⁿ and Tⁿ environments and peak area relations, (Q² + Q³)/Q⁴ and Qⁿ/Tⁿ units, on the basis of the deconvolution of ²⁹Si MAS NMR spectra of MSNs materials.

Material	δ, ppm (peak area, %)				δ (ppm)		peak area
Material	Q²	Q³	Q⁴	(Q² + Q³)/Q⁴	T²	T³	Q/T
MSNs	-93.2 (6.2)	-102.3 (44.6)	-112.0 (49.1)	1.0	---	---	---
MSNs-COOH_ext	-93.6 (3.2)	-102.7 (36.5)	-112.0 (60.2)	0.6	-57.8	-66.9	15.3
MSNs-BSA	-92.5 (3.7)	-102.8 (32.1)	-112.5 (64.0)	0.5	-58.3	-66.4	15.7

Table 4. Chemical shifts and populations (%) of the silicon Qn and Tn environments and peak area relations, (Q2 + Q3)/Q4 and Qn/Tn units, on the basis of the deconvolution of 29Si MAS NMR spectra of MSNs materials.