Synthesis, identification and application of the novel metal-organic framework Fe₃O₄@PAA@ZIF-8 for the drug delivery of ciprofloxacin and investigation of antibacterial activity

Figures & data

Figure 1. Ciprofloxacin structure.

Scheme 1. Simulation of the preparation of the Fe₃O₄@PAA@ZIF-8 framework, drug loading, release and antibacterial testing.

Figure 2. FTIR spectra of (a) Fe₃O₄@PAA, (b) Fe₃O₄@PAA@ZIF-8 and (c) Fe₃O₄@PAA@ZIF-8@CIP.

Figure 3. XRD pattern of (a) Fe₃O₄@PAA@ZIF-8 and (b) Fe₃O₄@PAA@ZIF-8@cip.

Figure 4. SEM images of (a) CIP, (b) Fe₃O₄@PAA@ZIF-8 and (c) Fe₃O₄@PAA@ZIF-8@CIP.

Figure 5. EDAX analysis of (a) Fe₃O₄@PAA@ZIF-8 and (b) Fe₃O₄@PAA@ZIF-8@CIP.

Figure 6. (a) BET Fe₃O₄@PAA@ZIF-8 analysis, (b) BET of Fe₃O₄@PAA@ZIF-8@CIP, (c) BJH of Fe₃O₄@PAA@ZIF-8 and (d) BJH Fe₃O₄@PAA@ZIF-8@CIP.

Figure 7. The release of cip from Fe₃O₄@PAA@ZIF-8 in two buffers at pH: 5 and pH: 7.4.

Table 1. Kinetic parameters of ciprofloxacin release.

	Zero order		Fist order		Huguchi model		Hixson		Kor’s peppas
	R^2	k0 (h^−1)	R^2	k1 (h^−1)	R^2	kH (h^−1/2)	R^2	kKP (h^−^n)	R^2	kHC (h^−1/3)
pH: 7.4	0.724	6.853	0.782	−0.041	0.881	21.029	0.504	0.273	0.727	0.675
pH: 5	0.672	2.41	0.675	0.138	0.735	11.327	0.457	0.0645	0.689	0.323

Figure 8. Results of antibacterial test (a) disk containing Escherichia coli bacteria and (b) disk containing Staphylococcus aureus bacteria.

Table 2. Antibacterial activity of CIP, Fe₃O₄@PAA@ZIF-8 and Fe₃O₄@PAA@ZIF-8@CIP.

Halo diameter
Bacterium	CIP	MOF	MOF-CIP
E. coli	15 mm	0	32 mm
S. aureus	0	0	15 mm