Silver Nanoparticles Embedded in Natural Rubber Films: Synthesis, Characterization, and Evaluation of In Vitro Toxicity

Table 1

Important infrared absorption bands of natural rubber (NR) film and NR film with AgNPs in different times of reduction.

NR film	NR/Ag30	NR/Ag60	NR/Ag90	NR/Ag120	Assignment
3290	3287	3286	3285	3283	N-H amide; O-H stretch
3036	3036	3038	3034	3033	=C-H stretch
2960	2960	2961	2960	2960	CH form CH3, CH from CH3, CH2
2915	2916	2914	2916	2916
2852	2850	2851	2850	2849
2724	2725	2726	2725	2725
1654	1662	1663	1663	1662	C=O (amide I)
1545	1543	—	—	—	(Amide II)
—	1517	1516	1515	1515	-R2N-H (secondary amine)
1445	1444	1446	1446	1446	Amide III, CH2, - CH3
1375	1374	1375	1375	1375
1309	1308	1308	1308	1308
1245	1247	1247	1246	1246
1125	1125	1126	1126	1126
1038	1040	1038	1039	1039	C-N/C-O
—	890	889	891	891	C=C-H
841	842	843	841	841	C=C-H
760	762	763	762	762	Amide III (N-H, C=O ), skeleton of isoprene
740	742	740	739	739

: stretching vibration; : symmetric stretching vibration; : antisymmetric stretching vibration; : in-plane bending vibration; as: antisymmetric in-plane bending vibration; : wagging vibration.