Table 4.

Engineered zinc alloys with antibacterial properties.

Alloy system	Sample	Preparation	Bacterial strains	Antibacterial test	Antibacterial effect	Antibacterial mechanisms	Application	Reference
Zn-Cu	Zn-4.0 wt.%Cu	Extrusion at 280°C	S. aureus	Live/dead cell staining	Effectively inhibited bacteria adhesion and biofilm formation	Release of Cu and Zn ions	Vascular stents	Niu et al., 2016
Zn-Cu	Zn-xCu (x=1, 2, 3, and 4 wt%) alloys	Extrusion at 280°C	S. aureus	Inhibition zone diameter (IZD) test	Antibacterial property was perfect when Cu concentration > 2 wt%	Release of Cu and Zn ions	Cardiovascular implants	Tang et al., 2017
Zn-Cu	Zn-xCu (x = 1, 2 and 4 wt%) alloys	Casting followed by heating to 350°C for 1 h and rolling	Mixed oral bacteria	Live/dead cell staining	Zn-4Cu alloy can inhibit biofilm formation of mixed oral bacteria	Release of Zn2+ and Cu2+ and increased pH (OH- release)	Osteosynthesis implants, especially in the craniomaxillofacial area	Li et al., 2019b
Zn-Cu-Fe	Zn-3Cu-xFe (x = 0, 0.2, 0.5 wt%)	Extrusion at 180°C	S. aureus, E. coli	Plate counting	Antibacterial properties of Zn-3Cu alloy were significantly improved by Fe alloying	Higher degradation rate and more Zn2+ and Cu2+ released	Vascular stents	Yue et al., 2020
Zn-Cu-Ti	Zn-1Cu-0.1Ti alloy	Casting and plastic deformation processes including hot-rolling and cold-rolling	S. aureus	IZD)	Good antibacterial effect with higher IZD than pure Zn	/	Bone fracture fixation applications such as bone screws and plates of biodegradable implants	Lin et al., 2020
Zn-Cu	Zn-xCu (x = 0, 0.5, 1 and 2 wt%)	extruding	S. aureus, S. epidermidis, MRSA, MRSE	Plate counting, live/dead staining, FESEM, TEM, real-time PCR of bacteria-related genes	Prevented bacterial adhesion and biofilm information	Inhibition of expression of genes related to wall synthesis, adhesion, colonization, biofilm formation, autolysis, and secretion of virulence factors in MRSA	Biodegradable orthopedic materials	Qu et al., 2020
	Zn-2Cu		MRSA	Rat femur intramedullary nail infection prevention model	Significant antibacterial activity against MRSA and reduction of inflammatory toxic side-effects and infection-related bone loss			Qu et al., 2020
Zn-Ag	Zn-4.0Ag alloy	Casting followed by thermomechanical treatment	S. gordonii	Crystal violet staining, live/dead cell staining	Effectively inhibited initial bacteria adhesion	Released Zn and Ag ions	Craniomaxillofacial osteosynthesis implants	Li et al., 2018
Zn-Ag-Au-V	Zn–2Ag–1.8Au–0.2V (wt.%) alloy	Casting followed by hot-rolling at 200°C and annealing at 390°C for 15 min	S. gordonii	Live/dead cell staining	Reduced plaque formation, inhibited bacterial adhesion and biofilm formation	Degradation products, such as released Zn2+, Ag+, and OH−	Craniomaxillofacial osteosynthesis implants	Li et al., 2019a
Zn-Mg	Zn-0.02 Mg alloy	Extrusion at 180°C	S. aureus, E. coli	Spread plate assay, live/dead viability assay, SEM	Strong antibacterial effect	Zn2+ damaged bacterial cell membranes and inhibited the multiple bacterial activities, such as nutrient transport and glycolysis	Cardiovascular stents	Lin et al., 2019
Zn-Al-Mg	Zn-0.5Al-xMg (x = 0, 0.1, 0.3 and 0.5 wt%)	Casting followed by suitable post-treatment	E. coli	Disc diffusion antibiotic sensitivity testing	Zn-0.5Al-0.5Mg significantly prohibited the growth of E. coli	/	Biodegradable orthopedic materials	Bakhsheshi-Rad et al., 2017
Zn-Mg-Sr	Zn-0.8Mg-0.2Sr (wt%)	Combination of casting, homogenization annealing, and extrusion at 200°C	S. gordonii	Live/dead staining	Effective inhibition of initial adhesion and biofilm formation	Released Zn2+ and alkaline shift in pH	Cranial and maxillofacial implants	Capek et al., 2021

“/” means “not mentioned”.