Table 1. C, H, and N Elemental Analysis Results of Cross-Linkers and Hydrogels^a.

	% C	% H	% N	C/N	DS	a	n
chitosan (CS)	40.95	6.96	7.41	5.53
L1	71.79	5.28
L2	72.71	5.98
L3	63.48	4.64
L4	65.72	5.56
CS-L1	45.64	4.74	3.12	14.63	0.65	1	14
CS-L2	43.43	5.89	5.57	7.80	0.15	1	15
CS-L3	32.43	4.61	1.91	16.98	0.82	1	14
CS-L4	34.74	5.52	4.29	8.10	0.17	1	15

^aDS: degree of substitution; a: the number of nitrogen; n: the number of carbon.