Evaluation of a chitosan-polyethylene glycol paste as a local antibiotic delivery device

Table 1 Zone of inhibition of antibacterial activity results reported as the average ± standard deviation of the inhibited growth diameter using vancomycin antibiotic eluates against Staphylococcus aureus and amikacin antibiotic eluates against Pseudomonas aeruginosa from 3A:2N, 1A:1N, and 2A:3N chitosan/polyethylene glycol paste variations and neutral 1% chitosan sponges after 24 h of direct contact (n = 5)

Group	Antibiotic eluate time points (h)
	1	3	6	12	24	48	72
Staphylococcus aureus zone of inhibition diameter (mm, n = 5) of vancomycin eluates
3A:2N CPP	13 ± 1.1	11 ± 0.5a	10 ± 0.4a	12 ± 0.4	12 ± 0.4	12 ± 0.5	10 ± 0.8
1A:1N CPP	13 ± 0.5	13 ± 1.1	11 ± 0.0a	12 ± 0.4	11 ± 0.4a	13 ± 0.4	10 ± 0.8
2A:3N CPP	12 ± 0.4	11 ± 1.1	11 ± 0.5	11 ± 0.5	11 ± 0.5	12 ± 0.0	8 ± 0.9
Neut 1% CS	12 ± 0.7c	7 ± 0.5	1 ± 3.1	0	0	0	0
Pseudomonas aeruginosa zone of inhibition diameter (mm, n = 5) of amikacin eluates
3A:2N CPP	10 ± 0.9	9 ± 2.3	10 ± 2.2	8 ± 1.5	8 ± 1.8	2 ± 3.8	0
1A:1N CPP	13 ± 2.2	10 ± 2.1	9 ± 1.1a	5 ± 3.2a	4 ± 3.8a	0	0
2A:3N CPP	11 ± 1.6	9 ± 1.3	8 ± 0.7a	9 ± 1.6	5 ± 3.2a	0	0
Neut 1% CS	10 ± 1.9c	5 ± 3.2	0	0	0	0	0

^aP < 0.05 vs hour 1 value;

^cP < 0.05 vs all other time points.