A Preliminary Exploration of the Efficacy of Gentamicin Sponges in the Prevention and Treatment of Wound Infections

Figures & data

Figure 1 Gentamicin sponge cut into pieces of 1×1 × 0.5 cm.

Figure 2 Wound suppuration rates of the rats with P. aeruginosa wound infection. *p < 0.05 compared with the 40 mg/mL air-dried sponge group.

Table 1 The Gentamicin-Loading for Each Sponge Type

Air-Dried Sponge Type	Original Weight	12h	24h	48h	96h	120h	p
40mg/mL	8.10(7.65–8.45)	13.30(12.65–13.55)	18.20(18.00–18.65)	24.90(23.35–25.75)	28.40(28.10–28.55)	29.10(26.85–30.10)	<0.01
16mg/mL	7.80(7.25–8.20)	8.70(8.45–9.20)	10.50(10.20–11.00)	12.90(12.60–13.30)	16.90(16.60–17.20)	16.10(15.85–17.15)	<0.01
8mg/mL	8.20(7.40–8.50)	8.60(7.95–8.95)	9.30(9.05–9.50)	10.10(9.85–10.35)	11.20(10.85–11.55)	11.20(10.35–12.55)	<0.01
4mg/mL	7.80(7.70–8.20)	8.10(7.80–8.30)	8.30(7.75–8.40)	9.40(9.20–9.70)	8.90(8.45–9.20)	8.20(7.75–8.95)	<0.01
1.6mg/mL	8.30(7.65–8.55)	8.40(7.95–8.75)	8.60(7.85–8.95)	8.80(8.65–9.05)	8.10(7.75–8.45)	7.10(6.75–7.50)	<0.01
0.8mg/mL	7.90(7.55–8.60)	8.10(7.85–8.70)	7.90(7.90–8.35)	8.80(8.45–9.15)	8.10(7.40–8.45)	6.70(6.20–7.10)	<0.01
0mg/mL	8.20(7.45–8.50)	8.30(7.70–8.55)	7.70(7.60–8.50)	7.90(7.60–8.15)	6.30(6.05–6.75)	5.90(5.40–6.50)	<0.01
p	0.92	<0.01	<0.01	<0.01	<0.01	<0.01

Notes: The data are presented as mg and are expressed as the median (interquartile range). Each group was repeated 5 times at each time points. The p-value was calculated by Kruskal–Wallis H-test to compare multiple groups or multiple time points. Mg/mL was the concentration of gentamicin solution that sponge immersed in. The quality and weight of the air-dried sponge began to change after about 48 hours.

Table 2 The Equation of Gentamicin-Loading by Sponge Type

Air-Dried Sponge Type	Drug Loading Equation of Sponge(mg)	R2
40mg/mL	0.5056x-0.0038x2+9.4828e-006(x3)	0.998
16mg/mL	0.0582x+0.0016x2–1.1666e-005(x3)	0.996
8mg/mL	0.0364x+0.0004x2–2.5544e-006(x3)	0.984
4mg/mL	−0.0020x+0.0008x2–5.4735e-006(x3)	0.915
1.6mg/mL	0.0097x+0.0004x2–3.3236e-006(x3)	0.916
0.8mg/mL	−0.0079x+0.0008x2–5.8723e-006(x3)	0.821

Notes: x was the immersed duration of sponge in gentamicin solution, R2 was the index of testing fitting degree of equation, range was 0 to 1 as fitting degree was bad to excellent.

Figure 3 Surface equation for the drug loading of the gentamicin sponge. The x-axis shows the duration of the sponge’s immersion in the gentamicin solution, the y-axis is the concentration of the gentamicin solution the sponge was immersed in, and the z-axis is the gentamicin loading of the sponge. The points represent the median of the drug loading for each group at each time point. The color ruler represents the gentamicin loading of the sponge, and the unit is mg.

Table 3 The Drug-Release of Different Types of Air-Dried Gentamicin-Saturated Sponges

Air-Dried Sponge Type	30Min	2h	6h	12h	24h	48h	96h	p
40mg/mL	16.30(16.00–16.80)	56.90(51.80–59.40)	166.50(160.65–174.25)	338.60(327.30–343.95)	847.20(840.55–851.10)	1103.40(1100.85–1107.50)	1371.30(1367.85–1372.900	<0.01
16mg/mL	4.70(4.15–5.65)	16.90(15.00–17.85)	43.00(40.85–46.55)	49.80(47.45–51.65)	247.10(240.70–250.35)	324.40(177.80–328.25)	402.20(400.30–403.95)	<0.01
8mg/mL	1.90(1.45–2.20)	5.70(5.05–6.50)	17.60(17.10–18.25)	40.90(37.60–42.00)	97.30(95.50–100.35)	138.10(132.50–140.65)	174.90(166.30–180.40)	<0.01
4mg/mL	0.90(0.35–1.15)	3.80(3.40–4.00)	8.70(8.25–9.00)	24.10(22.85–27.20)	74.20(72.25–76.55)	99.60(97.75–102.35)	144.90(142.15–150.20)	<0.01
1.6mg/mL	0.70(0.45–1.05)	3.10(2.60–3.70)	7.80(7.35–8.50)	19.30(18.35–20.00)	48.20(46.10–50.30)	64.40(63.30–67.25)	80.90(79.00–83.60)	<0.01
0.8mg/mL	0.80(0.45–1.00)	3.10(2.80–3.40)	8.10(7.50–8.25)	18.30(16.15–19.70)	47.40(45.45–50.05)	65.80(64.75–66.90)	80.60(79.85–82.35)	<0.01
0mg/mL	0	0	0	0	0	0	0
p	<0.01	<0.01	<0.01	<0.01	<0.01	<0.01	<0.01

Notes: The data are presented as ug/mL and are expressed as the median (interquartile range). Each group was repeated 5 times at each time point. ug/mL was the concentration of gentamicin in 10mL 0.9% physiological saline that air-dried gentamicin-saturated sponges were immersed in.

Table 4 The Equation of Gentamicin-Release by Sponge Type

Air-Dried Sponge Type	The Release of Air-Dried Gentamicin-Saturated Sponge(ug/mL)	R2
40mg/mL	39.5338x-0.3998x2+0.0014(x3)	0.994
16mg/mL	10.3348x-0.1210x2+0.0006(x3)	0.932
8mg/mL	4.3702x-0.0338x2+7.3831e-005(x3)	0.994
4mg/mL	3.0254x-0.0204x2+4.9293e-005(x3)	0.99
1.6mg/mL	2.1550x-0.0181x2+4.6371e-005(x3)	0.993
0.8mg/mL	2.0534x-0.0143x2+1.7261e-005(x3)	0.993

Notes: x was the immersed duration of sponge in saline, R2 was the index of testing fitting degree of equation, range was 0 to 1 as fitting degree was bad to excellent.

Figure 4 Surface equation for the drug release of the gentamicin sponge. The x-axis is the duration of the sponge’s immersion in the gentamicin solution, the y-axis is the concentration of the gentamicin solution the sponge was immersed in, and the z-axis is the gentamicin release of the air-dried sponge. The points represent the median of the drug release of each group at each time point. The color ruler represents the gentamicin release of the sponge, and the unit is µg/mL.

Figure 5 Wound suppuration rates of the rats with MSSA wound infection. *p < 0.05 compared with the 40 mg/mL air-dried sponge group.

Figure 6 The purpose of this study was to investigate the effects of gentamicin sponges in vitro and in vivo.