In Vitro Evaluation of Enrofloxacin-Loaded MLV Liposomes

Figures & data

TABLE 1 Formulations, codes, size, drug encapsulation capacity, and zeta potential values of MLVs

Variables	Codes	Molar ratios of DPPC: Cholesterol: ENF: SA or DCP	Mean vesicle size (μ m ± SD)	Encapsulation capacity (% ± SD)	mV (± SD)
DPPC molar ratio	A1	2.3: 4.3: 1: −	2.10 ± 0.12	51.0 ± 0.1	−35.9 ± 0.4
	A2	4.7: 4.3: 1: −	2.21 ± 0.14	67.2 ± 0.1	−37.3 ± 0.3
	A3	6.7: 4.3: 1: −	2.42 ± 0.11	81.4 ± 0.1	−38.1 ± 0.2
Cholesterol molar ratio	B1	4.7: 8.7: 1: −	2.54 ± 0.51	76.5 ± 0.1	−38.5 ± 0.4
	B2	4.7: 13.0: 1: −	3.05 ± 0.24	86.5 ± 0.1	−41.2 ± 0.3
	B3	4.7: 17.3: 1: −	3.31 ± 0.16	93.1 ± 0.1	−42.5 ± 0.3
ENF molar ratio	C1	9.3: 8.7: 1: −	2.22 ± 0.31	57.2 ± 0.1	−16.2 ± 0.2
	C2	9.3: 8.7: 2.7: −	1.83 ± 0.12	72.4 ± 0.1	−29.6 ± 0.4
	C3	9.3: 8.7: 3.7: −	1.89 ± 0.13	80.9 ± 0.2	−36.8 ± 0.3
α-tocopherol amount (mg)	D1	4.7: 4.3: 1: −	2.23 ± 0.13	70.8 ± 0.2	−36.4 ± 0.3
	D2	4.7: 4.3: 1: −	2.25 ± 0.10	74.7 ± 0.2	−36.9 ± 0.4
SA molar ratio	E1	7: 26: 1.5: 1	2.13 ± 0.72	75.3 ± 0.1	+12.0 ± 0.1
	E2	7: 26: 1.5: 2	2.40 ± 0.68	91.2 ± 0.1	+39.2 ± 0.3
	E3	7: 26: 1.5: 3	2.67 ± 0.93	96.7 ± 0.1	+58.8 ± 0.4
DCP molar ratio	F1	7: 26: 1.5: 1	2.47 ± 0.65	72.7 ± 0.1	− 51.3 ± 0.5
	F2	7: 26: 1.5: 2	2.06 ± 0.59	64.3 ± 0.1	−73.3 ± 0.4
	F3	7: 26: 1.5: 3	1.63 ± 0.11	57.9 ± 0.1	−91.3 ± 0.4

Only E formulations contained SA and only F formulations contained DCP.

Except D1 (30 mg) and D2 (45 mg), all formulations contained 15 mg α-tocopherol.

FIG. 2 ENF-loaded MLVs vesicle size distribution of E3 formulation (the molar ratios of DPPC: cholesterol: ENF: SA is 7: 26: 1.5: 3).

FIG. 1 Effect of lipid compositions (DPPC) [the molar ratios of DPPC: cholesterol: ENF are 2.3: 4.3: 1 (A1), 4.7: 4.3: 1 (A2), and 6.7: 4.3: 1 (A3)] on drug release from MLVs.

FIG. 3 Effect of lipid compositions (cholesterol) [the molar ratios of DPPC: cholesterol: ENF are 4.7: 8.7: 1 (B1), 4.7: 13: 1 (B2), and 4.7: 17.3: 1 (B3)] on drug release from MLVs.

FIG. 4 Effect of ENF concentrations (coded C1, C2, C3) on drug release from MLVs.

FIG. 5 Effect of SA molar ratios [the molar ratios of DPPC: cholesterol: ENF: SA are 7: 26: 1.5: 1 (E1), 7: 26: 1.5: 2 (E2), and 7: 26: 1.5: 3 (E3)] on drug release from MLVs.

FIG. 6 Effect of DCP molar ratios [the molar ratios of DPPC: cholesterol: ENF: DCP are 7: 26: 1.5: 1 (F1), 7: 26: 1.5: 2 (F2), and 7: 26: 1.5: 3 (F3)] on drug release from MLVs.

TABLE 2 Dissolution kinetic values (r²) of MLVs

Codes	Zero order (r^2)	First order (r^2)	Higuchi (r^2)	Hixon Crowel (r^2)
A1	0.9679	0.9589	0.9896	0.9930
A2	0.9818	0.7977	0.9664	0.9164
A3	0.9914	0.7905	0.9431	0.8988
B1	0.9912	0.8600	0.9333	0.9246
B2	0.9739	0.9005	0.8943	0.9319
B3	0.9648	0.9158	0.8777	0.9357
C1	0.9549	0.9351	0.9954	0.9861
C2	0.9974	0.9295	0.9609	0.9670
C3	0.9719	0.8916	0.8936	0.9255
E1	0.9932	0.8993	0.9404	0.9472
E2	0.9903	0.9585	0.9383	0.9739
E3	0.9845	0.9514	0.9184	0.9653
F1	0.9851	0.9587	0.9673	0.9739
F2	0.9643	0.9533	0.9805	0.9729
F3	0.9011	0.8774	0.9697	0.9731

TABLE 3 Drug content of MLVs during storage time

	Drug retention after storage in
Codes	15 days (% ± SD)	30 days (% ± SD)	60 days (% ± SD)
A1	97.1 ± 0.1	88.4 ± 0.0	85.6 ± 0.0
A2	98.1 ± 0.1	93.3 ± 0.1	87.7 ± 0.1
A3	98.5 ± 0.1	93.7 ± 0.1	92.4 ± 0.1
B1	96.0 ± 0.1	93.1 ± 0.1	92.1 ± 0.1
B2	97.1 ± 0.1	95.3 ± 0.1	94.6 ± 0.1
B3	98.0 ± 0.1	97.5 ± 0.1	97.0 ± 0.2
C1	90.2 ± 0.1	84.0 ± 0.0	80.8 ± 0.0
C2	97.0 ± 0.0	94.2 ± 0.1	93.2 ± 0.1
C3	98.8 ± 0.1	97.8 ± 0.1	97.1 ± 0.1
E1	96.1 ± 0.0	94.1 ± 0.0	92.7 ± 0.0
E2	99.0 ± 0.1	98.0 ± 0.1	95.6 ± 0.0
E3	98.7 ± 0.1	97.8 ± 0.1	96.9 ± 0.1
F1	95.7 ± 0.1	85.6 ± 0.1	62.8 ± 0.1
F2	91.3 ± 0.1	75.1 ± 0.1	46.4 ± 0.1
F3	86.1 ± 0.1	60.8 ± 0.1	37.3 ± 0.1