模拟体液中镁合金表面PCL-TiO2@Ag/γ-CD MOF纳米复合涂层的耐腐蚀、生物相容和抗菌性研究

doi:10.61558/2993-074X.3573

摘要/Abstract

摘要：

镁合金由于具有可降解性和生物相容性，被认为是生物植入物应用的有前景的候选材料。然而，其快速腐蚀仍然是实际应用的一个关键限制因素。本研究开发了一种多功能纳米复合涂层，旨在提高镁合金植入物的耐腐蚀性和抗菌性能。该涂层由表面修饰TiO₂@Ag核-壳纳米颗粒的γ-环糊精金属有机框架（γ-CD MOF）构成，并嵌入到聚己内酯（PCL）基体中（PCL-TiO₂@Ag/γ-CD MOF），与未修饰TiO₂@Ag核-壳纳米颗粒的涂层（PCL/γ-CD MOF）进行比较。模拟体液浸泡测试结果表明，虽然PCL-TiO₂@Ag/γ-CD MOF复合涂层初始的腐蚀速率高于PCL/γ-CD MOF涂层，但随着浸泡时间的推移，其性能显著改善。五天后，腐蚀抑制率达到95.44%，腐蚀速率降至1.70 mpy。此外，该复合涂层对大肠杆菌、假单胞菌和金黄色葡萄球菌均表现出较强的抗菌活性。研究证实，该涂层促进了成骨样MC3T3-E1细胞的生长和繁殖，从而具有无毒性和良好的生物相容性。本研究结果表明，PCL-TiO₂@Ag/γ-CD MOF纳米复合涂层在可降解镁合金植入物中具有良好的生物相容性、抗菌性和耐腐蚀性，在生物医学领域具有广阔的应用前景。

关键词: 抗菌涂层, 生物相容性, 防腐蚀涂层, γ-环糊精金属有机框架, TiO₂@Ag核-壳结构

Abstract:

Magnesium alloys are promising candidates for bio-implant applications due to their biodegradability and biocompatibility. However, their rapid corrosion remains a critical limitation. This study presents the development of a multifunctional nanocomposite coating designed to enhance the corrosion resistance and antibacterial properties of magnesium alloy implants. The coating comprised γ-cyclodextrin metal-organic frameworks (γ-CD MOFs) decorated with TiO₂@Ag core-shell nanoparticles, embedded in a polycaprolactone (PCL) matrix. Immersion tests in a simulated body fluid (SBF) revealed an initially higher corrosion rate for the PCL-TiO₂@Ag/γ-CD MOF coating compared to the coating without TiO₂@Ag nanoparticles; however, it demonstrated significant improvement over time. After five days, the corrosion inhibition reached 95.44%, with the corrosion rate decreasing to 1.70 mpy. Additionally, the composite coating exhibited strong antibacterial activity against Escherichia coli, Pseudomonas, and Staphylococcus aureus. Furthermore, MTT assays indicated that the coating facilitated the growth and proliferation of osteoblast-like MC3T3-E1 cells, confirming its nontoxicity and biocompatibility. These findings highlight the potential of the PCL-TiO₂@Ag/γ-CD MOF nanocomposite as a biocompatible, antibacterial, and corrosion-resistant coating for biodegradable magnesium implants, offering a promising solution for biomedical applications.

Key words: Antibacterial coating, Biocompatible, Anti-corrosion coating, γ-CD metal-organic framework, TiO₂@Ag core shell

萨拉·德赫甘-切纳尔, 哈米德·礼萨·扎雷, 扎赫拉·穆罕默德普尔, 玛丽亚姆·萨达特·米尔巴盖里-菲鲁扎巴德. 模拟体液中镁合金表面PCL-TiO₂@Ag/γ-CD MOF纳米复合涂层的耐腐蚀、生物相容和抗菌性研究[J]. 电化学（中英文）, 2025, 31(11): 2504241.

Sara Dehghan-Chenar, Hamid R. Zare, Zahra Mohammadpour, Maryam Sadat Mirbagheri-Firoozabad. Biocompatible and Antibacterial PCL-TiO₂@Ag/γ-CD MOF Nanocomposite Coating for Corrosion Resistance of Magnesium Alloy in Simulated Body Fluid[J]. Journal of Electrochemistry, 2025, 31(11): 2504241.

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链接本文: https://electrochem.xmu.edu.cn/CN/10.61558/2993-074X.3573

https://electrochem.xmu.edu.cn/CN/Y2025/V31/I11/2504241

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参考文献 51

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Parameter			E_corr (V)	I_corr (μA)	J_corr (μA·cm⁻²)	β_a (mV·dec^-1)	−β_c (mV·dec^-1)	CR (mpy)	IE%
Mg			−1.62±0.02	8.22±0.23	41.10±1.14	54±2.08	60±3.73	37.35±1.04	-
PCL			−1.58±0.02	1.37±0.06	6.87±0.31	48±4.49	72±2.05	6.24±0.28	83.27±0.36
PCL/γ-CD MOF	The immersion time in the SBF solution	0	−1.59±0.02	0.43±0.01	2.14±0.06	39±3.16	86±4.98	1.95±0.06	94.77±0.25
		1 day	−1.58±0.02	1.46±0.07	7.28±0.38	35±2.86	57±1.02	6.61±0.34	82.28±0.52
		3 days	−1.48±0.02	1.50±0.02	7.47±0.12	30±1.92	77±3.23	6.79±0.11	81.81±0.80
		5 days	-1.61±0.02	6.73±0.20	33.68±1.02	70±1.63	87±4.11	30.61±0.93	18.04±0.21
PCL-TiO₂@Ag/ γ-CD MOF	The immersion time in the SBF solution	0	−1.55±0.02	2.48±0.06	12.38±0.31	39±2.16	70±4.49	11.25±0.28	69.87±1.57
		1 day	−1.50±0.02	0.84±0.03	4.19±0.14	23±3.68	89±4.11	3.81±0.13	89.79±0.62
		3 days	−1.49±0.02	0.50±0.01	2.52±0.06	20±2.94	56±2.86	2.30±0.05	93.85±0.03
		5 days	-1.48±0.02	0.37±0.03	1.87±0.16	43±4.49	46±3.30	1.70±0.14	95.44±0.52

Parameters	Mg	PCL	PCL/γ-CD MOF				PCL-TiO₂@Ag/γ-CD MOF
			The immersion time in the SBF solution				The immersion time in the SBF solution
			0	1 day	3 days	5 days	0	1 day	3 days	5 days
R_s	2.64	1.26	2.10	1.43	2.12	1.90	2.52	2.38	2.19	2.3
C_out	1.19×10^-7	1.04×10^-7	5.99×10^-8	6.42×10^-8	7.97×10^-8	1.26×10^-7	7.19×10^-8	6.82×10^-8	5.77×10^-8	3.77×10^-8
R_out	19.31	27.10	50.78	32.52	26.18	20.69	28.84	36.82	38.82	52.5
C_in	4.30×10^-3	6.48×10^-4	2.23×10^-4	9.13×10^-4	2.24×10^-3	8.40×10^-4	1.08×10^v3	3.54×10^-4	3.38×10^-4	9.05×10^-5
R_in	28.84	519.8	859.4	292.4	232.2	95.46	281.2	548.8	570.6	988.4
CPE_ct	3.07×10^-5	1.39×10^-5	5.40×10^-6	4.65×10^-5	5.12×10^-5	7.53×10^-5	4.20×10^-5	3.05×10^-5	1.92×10^-5	1.67×10^-5
n	0.81	0.72	0.75	0.70	0.75	0.66	0.64	0.80	0.79	0.55
R_ct	140.46	923.4	1659.0	803.4	751.0	197.6	737.6	1120.0	1530.0	2220
L	2090	4772	18020	17800	27540	27480	10460	14940	14259	1980
R_L	524.0	275.6	3254.0	1012.8	609.8	706.6	480.4	848.2	915.0	819.0
χ²×10^-3	3.63	1.04	2.28	1.04	0.83	4.31	1.64	2.18	0.95	9.90
IE%	-	84.78	91.53	82.51	81.29	28.91	80.95	87.46	90.81	93.67

模拟体液中镁合金表面PCL-TiO₂@Ag/γ-CD MOF纳米复合涂层的耐腐蚀、生物相容和抗菌性研究

Biocompatible and Antibacterial PCL-TiO₂@Ag/γ-CD MOF Nanocomposite Coating for Corrosion Resistance of Magnesium Alloy in Simulated Body Fluid

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