REFERENCES
1. Zhang, Z.; Zheng, G.; Li, H.; et al. Anti-bacterium influenced corrosion effect of antibacterial Ti-3Cu alloy in Staphylococcus aureus suspension for biomedical application. Mater. Sci. Eng. C. 2019, 94, 376-84.
2. Korda, A. A.; Munawaroh, S.; Basuki, E. A. The antimicrobial activity and characterization of the cast titanium copper alloys with variations of copper content. IOP. Conf. Ser. Mater. Sci. Eng. 2019, 547, 012002.
3. Zhang, E.; Li, F.; Wang, H.; et al. A new antibacterial titanium-copper sintered alloy: preparation and antibacterial property. Mater. Sci. Eng. C. 2013, 33, 4280-7.
4. Liu, J.; Li, F.; Liu, C.; et al. Effect of Cu content on the antibacterial activity of titanium-copper sintered alloys. Mater. Sci. Eng. C. 2014, 35, 392-400.
5. Liu, R.; Memarzadeh, K.; Chang, B.; et al. Antibacterial effect of copper-bearing titanium alloy (Ti-Cu) against streptococcus mutans and porphyromonas gingivalis. Sci. Rep. 2016, 6, 29985.
6. Liu, R.; Tang, Y.; Zeng, L.; et al. In vitro and in vivo studies of anti-bacterial copper-bearing titanium alloy for dental application. Dent. Mater. 2018, 34, 1112-26.
7. Fowler, L.; Janson, O.; Engqvist, H.; Norgren, S.; Öhman-Mägi, C. Antibacterial investigation of titanium-copper alloys using luminescent Staphylococcus epidermidis in a direct contact test. Mater. Sci. Eng. C. 2019, 97, 707-14.
8. Bai, B.; Zhang, E.; Liu, J.; Zhu, J. The anti-bacterial activity of titanium-copper sintered alloy against Porphyromonas gingivalis in vitro. Dent. Mater. J. 2016, 35, 659-67.
9. Simonelli, M.; Aboulkhair, N. T.; Cohen, P.; et al. A comparison of Ti-6Al-4V in-situ alloying in selective laser melting using simply-mixed and satellited powder blend feedstocks. Mater. Charact. 2018, 143, 118-26.
10. Ma, M.; Zhao, M.; Ji, R.; Guo, Y.; Li, D.; Zeng, S. Adjusting the dose of ag-ion implantation on TiN-Ag-modified SLA-Ti creates different micronanostructures: implications on bacteriostasis, biocompatibility, and osteogenesis in dental implants. ACS. Omega. 2023, 8, 39269-78.
11. Luo, S.; Paisansuthichol, S.; Tran, N.; Qian, M.; Song, T. Biomedical titanium-tantalum alloys for orthopedic implant applications: From manufacturing to biological performance. Bioact. Mater. 2026, 61, 830-78.
12. Mitra, I.; Bose, S.; Dernell, W. S.; et al. 3D Printing in alloy design to improve biocompatibility in metallic implants. Mater. Today. 2021, 45, 20-34.
13. Fu, S.; Zhang, Y.; Qin, G.; Zhang, E. Antibacterial effect of Ti Ag alloy motivated by Ag-containing phases. Mater. Sci. Eng. C. 2021, 128, 112266.
14. Mosallanejad, M.; Niroumand, B.; Aversa, A.; Manfredi, D.; Saboori, A. Laser powder bed fusion in-situ alloying of Ti-5%Cu alloy: process-structure relationships. J. Alloys. Compd. 2021, 857, 157558.
15. Soro, N.; Attar, H.; Brodie, E.; Veidt, M.; Molotnikov, A.; Dargusch, M. S. Evaluation of the mechanical compatibility of additively manufactured porous Ti-25Ta alloy for load-bearing implant applications. J. Mech. Behav. Biomed. Mater. 2019, 97, 149-58.
16. Fischer, M.; Joguet, D.; Robin, G.; Peltier, L.; Laheurte, P. In situ elaboration of a binary Ti-26Nb alloy by selective laser melting of elemental titanium and niobium mixed powders. Mater. Sci. Eng. C. 2016, 62, 852-9.
17. Polozov, I.; Sufiiarov, V.; Popovich, A.; Masaylo, D.; Grigoriev, A. Synthesis of Ti-5Al, Ti-6Al-7Nb, and Ti-22Al-25Nb alloys from elemental powders using powder-bed fusion additive manufacturing. J. Alloys. Compd. 2018, 763, 436-45.
18. Kang, N.; Li, Y.; Lin, X.; Feng, E.; Huang, W. Microstructure and tensile properties of Ti-Mo alloys manufactured via using laser powder bed fusion. J. Alloys. Compd. 2019, 771, 877-84.
19. Grigoriev, A.; Polozov, I.; Sufiiarov, V.; Popovich, A. In-situ synthesis of Ti2AlNb-based intermetallic alloy by selective laser melting. J. Alloys. Compd. 2017, 704, 434-42.
20. Rabbitt, D.; O’kelly, P.; Villapún, V. M.; Carter, L. N.; Knowles, A. J.; Cox, S. C. Antimicrobial titanium-copper alloys: the role of microstructure in arc-melted compositions. Adv. Eng. Mater. 2025, 27, 2500347.
21. Rabbitt, D. L. A. Development of antimicrobial metal alloys. University of Birmingham; 2025. Available from: https://etheses.bham.ac.uk/id/eprint/16231/ [Last accessed on 21 Aug 2026].
22. Rabbitt, D.; Villapún, V. M.; Carter, L. N.; et al. Rethinking biomedical titanium alloy design: a review of challenges from biological and manufacturing perspectives. Adv. Healthc. Mater. 2024, 14, 2403129.
23. Zhang, L. C.; Chen, L. Y. A review on biomedical titanium alloys: recent progress and prospect. Adv. Eng. Mater. 2019, 21, 1801215.
24. Wu, C.; Lin, P.; Huang, S.; et al. Revisiting alloy design of low-modulus biomedical β-Ti alloys using an artificial neural network. Materialia 2022, 21, 101313.
25. Stráský, J.; Harcuba, P.; Václavová, K.; et al. Increasing strength of a biomedical Ti-Nb-Ta-Zr alloy by alloying with Fe, Si and O. J. Mech. Behav. Biomed. Mater. 2017, 71, 329-36.
26. Scipioni Bertoli, U.; Guss, G.; Wu, S.; Matthews, M. J.; Schoenung, J. M. In-situ characterization of laser-powder interaction and cooling rates through high-speed imaging of powder bed fusion additive manufacturing. Mater. Des. 2017, 135, 385-96.
27. Takata, N.; Liu, M.; Kodaira, H.; Suzuki, A.; Kobashi, M. Anomalous strengthening by supersaturated solid solutions of selectively laser melted Al-Si-based alloys. Addit. Manuf. 2020, 33, 101152.
28. Farshidianfar, M. H.; Khajepour, A.; Gerlich, A. Real-time control of microstructure in laser additive manufacturing. Int. J. Adv. Manuf. Technol. 2015, 82, 1173-86.
29. Thampy, V.; Fong, A. Y.; Calta, N. P.; et al. Subsurface cooling rates and microstructural response during laser based metal additive manufacturing. Sci. Rep. 2020, 10, 1981.
30. Liu, Y.; Jiang, W.; Chen, Z.; Xu, Q.; Zhang, Z.; He, J. Optimization of processing parameters and microstructure evolution of (TiB+La2O3)/Ti6Al4V manufactured by laser melting deposition. J. Mater. Res. Technol. 2023, 24, 8086-97.
31. Zhou, J.; Li, H.; Yu, Y.; et al. Fabrication of functionally graded materials from a single material by selective evaporation in electron beam powder bed fusion. Mater. Sci. Eng. A. 2020, 793, 139827.
32. Majumdar, J. D.; Pinkerton, A.; Liu, Z.; Manna, I.; Li, L. Microstructure characterisation and process optimization of laser assisted rapid fabrication of 316L stainless steel. Appl. Surf. Sci. 2005, 247, 320-7.
33. Ghouse, S.; Babu, S.; Van Arkel, R. J.; Nai, K.; Hooper, P. A.; Jeffers, J. R. The influence of laser parameters and scanning strategies on the mechanical properties of a stochastic porous material. Mater. Des. 2017, 131, 498-508.
34. Carter, L. N.; Martin, C.; Withers, P. J.; Attallah, M. M. The influence of the laser scan strategy on grain structure and cracking behaviour in SLM powder-bed fabricated nickel superalloy. J. Alloys. Compd. 2014, 615, 338-47.
35. Ng, C.; Bermingham, M.; Dargusch, M. Controlling grain size, morphology and texture in additively manufactured β-titanium alloy with super transus hot isostatic pressing. Addit. Manuf. 2022, 59, 103176.
36. Wang, Z.; Xiao, Z.; Tse, Y.; Huang, C.; Zhang, W. Optimization of processing parameters and establishment of a relationship between microstructure and mechanical properties of SLM titanium alloy. Opt. Laser. Technol. 2019, 112, 159-67.
37. Hassanin, H.; El-sayed, M. A.; Ahmadein, M.; et al. Optimising surface roughness and density in titanium fabrication via laser powder bed fusion. Micromachines 2023, 14, 1642.
38. Li, Z.; Kucukkoc, I.; Zhang, D. Z.; Liu, F. Optimising the process parameters of selective laser melting for the fabrication of Ti6Al4V alloy. Rapid. Prototyp. J. 2018, 24, 150-9.
39. Bocchetta, P.; Chen, L.; Tardelli, J. D. C.; Reis, A. C. D.; Almeraya-Calderón, F.; Leo, P. Passive layers and corrosion resistance of biomedical Ti-6Al-4V and β-Ti alloys. Coatings 2021, 11, 487.
40. Rack, H.; Qazi, J. Titanium alloys for biomedical applications. Mater. Sci. Eng. C. 2006, 26, 1269-77.
41. Mahmoudi, P.; Akbarpour, M. R.; Lakeh, H. B.; Jing, F.; Hadidi, M. R.; Akhavan, B. Antibacterial Ti-Cu implants: a critical review on mechanisms of action. Mater. Today. Bio. 2022, 17, 100447.
42. Tran, T. Q.; Chinnappan, A.; Lee, J. K. Y.; et al. 3D printing of highly pure copper. Metals 2019, 9, 756.
43. Ngo, T. D.; Kashani, A.; Imbalzano, G.; Nguyen, K. T.; Hui, D. Additive manufacturing (3D printing): a review of materials, methods, applications and challenges. Compos. Part. B. Eng. 2018, 143, 172-96.
44. Jiang, Q.; Zhang, P.; Yu, Z.; et al. A review on additive manufacturing of pure copper. Coatings 2021, 11, 740.
45. Wang, J. C.; Li, Y. H.; Yuan, Y. J.; Liu, Y. J.; Zhang, L. C. Advances in laser powder bed fusion of copper and copper alloys: microstructure, mechanical behavior, and conductivity. cMat 2025, 2, e70021.
46. Zhu, M.; Miao, J.; Zhou, X.; Zhang, E.; Liu, Z.; Yang, H. Corrosion resistance and antibacterial properties of Ti-3Cu alloy prepared by selective laser melting. Trans. Nonferrous. Met. Soc. China. 2025, 35, 143-56.
47. Zhang, E.; Ren, J.; Li, S.; Yang, L.; Qin, G. Optimization of mechanical properties, biocorrosion properties and antibacterial properties of as-cast Ti-Cu alloys. Biomed. Mater. 2016, 11, 065001.
48. Bao, M.; Liu, Y.; Wang, X.; et al. Optimization of mechanical properties, biocorrosion properties and antibacterial properties of wrought Ti-3Cu alloy by heat treatment. Bioact. Mater. 2018, 3, 28-38.
49. Ji, H.; Zhao, M.; Xie, B.; et al. Corrosion and antibacterial performance of novel selective-laser-melted (SLMed) Ti-xCu biomedical alloys. J. Alloys. Compd. 2021, 864, 158415.
50. Tao, S.; Xu, J.; Yuan, L.; Luo, J.; Zheng, Y. Microstructure, mechanical properties and antibacterial properties of the microwave sintered porous Ti-3Cu alloys. J. Alloys. Compd. 2020, 812, 152142.
52. Zhang, C.; Deng, Y.; Chong, M.; Zhang, Z.; Tan, Y. Entropy-based re-sampling method on SAR class imbalance target detection. ISPRS. J. Photogramm. Remote. Sens. 2024, 209, 432-47.
53. Hedberg, Y. S.; Žnidaršič, M.; Herting, G.; Milošev, I.; Odnevall Wallinder, I. Mechanistic insight on the combined effect of albumin and hydrogen peroxide on surface oxide composition and extent of metal release from Ti6Al4V. J. Biomed. Mater. Res. 2018, 107, 858-67.
54. Gussev, M. N.; Busby, J. T.; Field, K. G.; Sokolov, M. A.; Gray, S. E. Role of scale factor during tensile testing of small specimens. In sixth international symposium on small specimen test techniques, ASTM International; 2014.
55. Gupta, T. T.; Gupta, N. K.; Pestrak, M. J.; et al. Staphylococcus aureus aggregates on orthopedic materials under varying levels of shear stress. Appl. Environ. Microbiol. 2020, 86, e01234-20.
56. Viroxy. ISO 22196:2011. Available from: https://www.viroxylabs.com/microbiological-testing-services/disinfectant-efficacy-testing/iso-221962011/ [Last accessed on 14 Aug 2026].
57. Schneider, C. A.; Rasband, W. S.; Eliceiri, K. W. NIH image to ImageJ: 25 years of image analysis. Nat. Methods. 2012, 9, 671-5.
58. Zhang, E.; Wang, X.; Chen, M.; Hou, B. Effect of the existing form of Cu element on the mechanical properties, bio-corrosion and antibacterial properties of Ti-Cu alloys for biomedical application. Mater. Sci. Eng. C. 2016, 69, 1210-21.
59. Yang, H. L.; Zou, L.; Juaim, A. N.; et al. Copper release and ROS in antibacterial activity of Ti-Cu alloys against implant-associated infection. Rare. Metals. 2023, 42, 2007-19.
60. Mikolay, A.; Huggett, S.; Tikana, L.; Grass, G.; Braun, J.; Nies, D. H. Survival of bacteria on metallic copper surfaces in a hospital trial. Appl. Microbiol. Biotechnol. 2010, 87, 1875-9.
61. Jeromen, A.; Nair, A.; Rodič, P.; et al. DED-LB manufactured Ti-6Al-4V-4Cu alloy: materials development, characterization, and in vivo biocompatibility. J. Mater. Res. Technol. 2025, 39, 5597-611.
62. Hedberg, J.; Karlsson, H. L.; Hedberg, Y.; Blomberg, E.; Odnevall Wallinder, I. The importance of extracellular speciation and corrosion of copper nanoparticles on lung cell membrane integrity. Colloid. Surface. B. 2016, 141, 291-300.
63. Midander, K.; Cronholm, P.; Karlsson, H. L.; et al. Surface characteristics, copper release, and toxicity of nano- and micrometer-sized copper and copper(II) oxide particles: a cross-disciplinary study. Small 2009, 5, 389-99.
64. Tengvall, P.; Lundström, I.; Sjöqvist, L.; Elwing, H.; Bjursten, L. M. Titanium-hydrogen peroxide interaction: model studies of the influence of the inflammatory response on titanium implants. Biomaterials 1989, 10, 166-75.
65. Thompson, G.; Puleo, D. Ti-6Al-4V ion solution inhibition of osteogenic cell phenotype as a function of differentiation timecourse in vitro. Biomaterials 1996, 17, 1949-54.
66. Costa, B. C.; Tokuhara, C. K.; Rocha, L. A.; Oliveira, R. C.; Lisboa-Filho, P. N.; Costa Pessoa, J. Vanadium ionic species from degradation of Ti-6Al-4V metallic implants: in vitro cytotoxicity and speciation evaluation. Mater. Sci. Eng. C. 2019, 96, 730-9.
67. Ghosh, S. K.; Saha, R.; Saha, B. Toxicity of inorganic vanadium compounds. Res. Chem. Intermed. 2014, 41, 4873-97.
69. Kosiba, K.; Gustmann, T.; Kim, J. T.; et al. Experimental cooling rates during high-power laser powder bed fusion at varying processing conditions. J. Alloys. Compd. 2023, 967, 171773.
70. Akbarpour, M. R.; Moniri Javadhesari, S. Densification and mechanical and antibacterial properties of low-cost powder metallurgy TiCu intermetallic alloy as a potential biomedical material. JOM 2020, 72, 3262-8.
71. Li, Y. H.; Chen, N.; Cui, H. T.; Wang, F. Fabrication and characterization of porous Ti-10Cu alloy for biomedical application. J. Alloys. Compd. 2017, 723, 967-73.
72. Korda, A. A.; Munawaroh, S.; Basuki, E. A. The antimicrobial activity and characterization of the cast titanium copper alloys with variations of copper content. IOP. Conf. Ser. Mater. Sci. Eng. 2019, 547, 012002.
73. Crnčević, N.; El Sayed, A.; Hsino, M.; et al. Effect of copper salts on Escherichia coli and enterococcus faecalis biofilms in pipeline systems: implications for microbial control and hydraulic performance. Appl. Sci. 2025, 15, 8042.
74. Reyes-Jara, A.; Cordero, N.; Aguirre, J.; Troncoso, M.; Figueroa, G. Antibacterial effect of copper on microorganisms isolated from bovine mastitis. Front. Microbiol. 2016, 7, 626.
75. Benhalima, L.; Amri, S.; Bensouilah, M.; Ouzrout, R. Antibacterial effect of copper sulfate against multi-drug resistant nosocomial pathogens isolated from clinical samples: effect of copper sulfate on clinical isolates. Pak. J. Med. Sci. 2019, 35, 1322-8.
76. Zevenhuizen, L. P. T. M.; Dolfing, J.; Eshuis, E. J.; Scholten-Koerselman, I. J. Inhibitory effects of copper on bacteria related to the free ion concentration. Microb. Ecol. 1979, 5, 139-46.
77. Honkanen, M.; Jämsen, E.; Karppelin, M.; Huttunen, R.; Eskelinen, A.; Syrjänen, J. Periprosthetic joint infections as a consequence of bacteremia. Open. Forum. Infect. Dis. 2019, 6, ofz218.
78. Pina, V. G.; Amigó, V.; Muñoz, A. I. Microstructural, electrochemical and tribo-electrochemical characterisation of titanium-copper biomedical alloys. Corros. Sci. 2016, 109, 115-25.
79. Luo, L.; Zhong, Q.; Chen, Z.; et al. 3D-printed copper-containing tailored titanium alloys with corrosion resistance, biocompatibility, and anti-inflammatory properties for enhanced guided bone regeneration. Front. Bioeng. Biotechnol. 2025, 13, 1647678.
80. Li, J.; Zhang, D.; Chen, X.; et al. Laser directed energy deposited, ultrafine-grained functional titanium-copper alloys tailored for marine environments: Antibacterial and anti-microbial corrosion studies. J. Mater. Sci. Technol. 2023, 166, 21-33.
81. Liu, H.; Zhang, X.; Shi, L.; et al. Effect of Cu content on the properties of laser powder bed fused biomedical titanium alloys. J. Mater. Res. Technol. 2024, 30, 8992-8.
82. Thijs, L.; Verhaeghe, F.; Craeghs, T.; Humbeeck, J. V.; Kruth, J. A study of the microstructural evolution during selective laser melting of Ti-6Al-4V. Acta. Mater. 2010, 58, 3303-12.
83. Xu, W.; Brandt, M.; Sun, S.; et al. Additive manufacturing of strong and ductile Ti-6Al-4V by selective laser melting via in situ martensite decomposition. Acta. Mater. 2015, 85, 74-84.
84. Kwabena Adomako, N.; Haghdadi, N.; Primig, S. Electron and laser-based additive manufacturing of Ni-based superalloys: a review of heterogeneities in microstructure and mechanical properties. Mater. Des. 2022, 223, 111245.
85. Popovich, V.; Borisov, E.; Popovich, A.; Sufiiarov, V.; Masaylo, D.; Alzina, L. Functionally graded inconel 718 processed by additive manufacturing: crystallographic texture, anisotropy of microstructure and mechanical properties. Mater. Des. 2017, 114, 441-9.
86. Chen, L.; Cui, Y.; Zhang, L. Recent Development in beta titanium alloys for biomedical applications. Metals 2020, 10, 1139.
87. Schmidt, A. H.; Swiontkowski, M. F. Pathophysiology of infections after internal fixation of fractures. J. Am. Acad. Orthop. Surg. 2000, 8, 285-91.
88. Foster, A. L.; Moriarty, T. F.; Zalavras, C.; et al. The influence of biomechanical stability on bone healing and fracture-related infection: the legacy of Stephan Perren. Injury 2021, 52, 43-52.
89. Grass, G.; Rensing, C.; Solioz, M. Metallic copper as an antimicrobial surface. Appl. Environ. Microbiol. 2011, 77, 1541-7.
90. Gaetke, L. M.; Chow-Johnson, H. S.; Chow, C. K. Copper: toxicological relevance and mechanisms. Arch. Toxicol. 2014, 88, 1929-38.
91. Bandyopadhyay, A.; Mitra, I.; Ciliveri, S.; et al. Additively manufactured Ti-Ta-Cu alloys for the next-generation load-bearing implants. Int. J. Extrem. Manuf. 2023, 6, 015503.
92. Berg, J.; Thorsen, M. K.; Holm, P. E.; Jensen, J.; Nybroe, O.; Brandt, K. K. Cu exposure under field conditions coselects for antibiotic resistance as determined by a novel cultivation-independent bacterial community tolerance assay. Environ. Sci. Technol. 2010, 44, 8724-8.
93. Gaurav, A.; Bakht, P.; Saini, M.; Pandey, S.; Pathania, R. Role of bacterial efflux pumps in antibiotic resistance, virulence, and strategies to discover novel efflux pump inhibitors. Microbiology 2023, 169, 001333.
94. Pietsch, F.; O'neill, A.; Ivask, A.; et al. Selection of resistance by antimicrobial coatings in the healthcare setting. J. Hosp. Infect. 2020, 106, 115-25.
95. De Gaetano, G. V.; Lentini, G.; Famà, A.; Coppolino, F.; Beninati, C. Antimicrobial resistance: two-component regulatory systems and multidrug efflux pumps. Antibiotics 2023, 12, 965.
96. Boyd-Vorsah, S.; Torres, Ortiz. A.; Pulido, S.; Bui, B.; Yeh, P. J. Survival, resistance, and fitness dynamics of Escherichia coli populations after prolonged exposure to copper. Evol. Med. Public. Health. 2025, 13, 176-87.
97. Xu, Y.; Tan, L.; Li, Q.; Zheng, X.; Liu, W. Sublethal concentrations of heavy metals Cu2+ and Zn2+ can induce the emergence of bacterial multidrug resistance. Environ. Technol. Innov. 2022, 27, 102379.
98. Bartolomeu, F.; Costa, M.; Alves, N.; Miranda, G.; Silva, F. Additive manufacturing of NiTi-Ti6Al4V multi-material cellular structures targeting orthopedic implants. Opt. Lasers. Eng. 2020, 134, 106208.
