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Materials Science in Additive Manufacturing Additive manufacturing of 316L-Cu alloys

A1 B1 C1

A2 B2 C2

A3 B3 C3

D E

Figure 5. SEM imaging and quantification of visible S. aureus CFU. (A1, A2, A3) 316L control shows significantly higher CFU count than (B1, B2, B3)
SS-3Cu and (C1, C2, C3) SS-5Cu across all time points. These images are taken at ×5000. The inset image within Figure 5C1 is taken at ×40000. (D) CFU
quantification of SEM images with n = 3 per condition. Statistically significant values are marked as *P < 0.05, **P < 0.01, ***P < 0.001. (E) Normalized
bacterial viability for each time point
Abbreviations: CFU: Colony-forming units; SEM: Scanning electron microscopy
While the magnitude of property variation from the cellular contents and eventual cell death. An alternative
base 316L is minor, this lack of consensus highlights the hypothesis suggests that Cu ions penetrate the membrane
variability of material properties in AM-produced alloys and generate reactive oxygen species, which causes oxidative
and their dependence on processing parameters. stress that damages cellular contents, including DNA. Both
8,31
4.2. Antibacterial properties theories converge on the same outcome: cell death resulting
from membrane damage due to surface contact with Cu.
While Cu is known to have antibacterial properties, its
exact method of killing bacteria remains a topic of ongoing Although Cu alloying has great antibacterial potential,
research, with no single definite consensus. One accepted more established and trusted infection prevention methods
theory of contact killing involves the ability of released Cu are widely employed. Antibiotic medication may be
ions to degrade the cell membrane, leading to leakage of administered post-surgery to address infection risks, but

Volume 4 Issue 1 (2025) 8 doi: 10.36922/msam.7357