Table 1.
The methodological details of the included studies in which Ag was used as the antibacterial agent.
| PEO Processing Parameters | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Substrate | # of Exp Groups with Ag | Electrolyte | Voltage (V) | Current Density (A/dm2) | Time (min) | Surface Topography |
Phase Composition |
Surface Content of Ag | Cumulative Ag Ion Release (ppb) | Ref. |
| Ti6Al7Nb | 2 | 0.02 M CA, 0.15 M Ca-GP, and (0.3 and 3.0) g/L Ag NPs | - | 20 | 5 | Porous structures (<5 µm) |
- | - | 12—day 7 89—day 7 |
[15] |
| Ti6Al4V | 2 | 0.15 M CA, 0.02 M Ca-GP, and 3.0 g/L Ag NPs | - | 20 | 5 | Micro- and nano-porous structures with Ag NPs of 7–25 nm | Ti, anatase, rutile, HA, CaTiO3, and Ca3(PO4)2 | - | 138—day 28 600—day 28 |
[31] |
| Ti6Al7Nb | 1 | 0.15 M CA, 0.02 M Ca-GP, and 3.0 g/L Ag NPs | - | 20 | 5 | Porous structures (<3 µm) with Ag NPs of 37 nm | Ti, anatase, and rutile | 0.03 wt% | - | [32] |
| CP-Ti | 3 | 0.4 M CA, 0.04 M β-GP, and (0.00003, 0.00006 and 0.004 M) AgNO3 | 380–420 | - | 180 | Irregular and rough morphology with spherical particles and flakes | Rutile, α-TCP, β-Ca2P2O7, and HA | <0.1 wt% <0.1 wt% 0.21–0.45 wt% |
- | [35] |
| CP-Ti | 1 | 0.15 M CA, 0.05 M NaH2PO4, 0.25 mM AgNO3 | 280–320 | - | 6 | Porous surface with 1.5 µm pore size and 8.5% pore density | Anatase, rutile | 0.13 at% | 48—day 18 | [48] |
| CP-Ti | 3 | 0.4 g/L NaOH, 4.0 g/L NaH2PO4, and 0.1–1.0 g/L Ag NPs | 400 | - | 5 | Homogenous porous surface layer | Ti, anatase, rutile | 1.5 at% 3.5 at% 5.8 at% |
40—day 7 200—day 7 240—day 7 |
[49] |
| Ti6Al4V | 2 | 0.15 M CA, 0.02 M Ca-GP, 0.3 M SrA, and 3.0 g/L Ag NPs |
- | 20 | 5 | Uniform coverage with a micro-/nanopores. Addition of SrA resulted in smaller pore size. |
Ti, anatase, rutile, HA, SrTiO3, Sr2Ca(PO4)2 | - | 1500—day 28 1800—day 28 |
[50] |
| CP-Ti | 3 | 100 mM Ca-GP, 150 mM CA, 0,5, and 10 mM AgNO3 | - | 2.51 | 10 | Porous oxide layer for 0 and 5 mM Ag, non-porous surface for 10 mM Ag | Anatase, α-Ti | 0.5 at% 1.5 at% 3.0 at% |
300—day 28 3000—day 28 104—day 28 |
[51] |
| CP-Ti, Ti-40Nb | 2 | Na2HPO4, NaOH, β-Ca3(PO4)2, and 0.3—1 g/L AgNO3 | 200–450 | - | 5–10 | Uniformly distributed β-TCP particles over a porous surface with 0–8 µm pore sizes | Anatase, α-TCP, β-TCP | 0.2 at% 0.8 at% |
- | [52] |
| CP-Ti | 4 | Na2HPO4, NaOH, β-Ca3(PO4)2, and 1 g/L AgNO3 | 200–450 | - | 5–10 | Uniformly distributed β-TCP particles over a porous surface with 0–8 µm pore sizes | Anatase, α-TCP, β-TCP | 0.3 at% 0.5 at% 0.8 at% |
- | [53] |
| CP-Ti | 3 | 0.1 M CA, 0.06 M NaH2P, and 0.01—0.05 M Ag2O NPs | - | 10 | 10 | Porous structure with typical micro-sized pores | Anatase, rutile | 1.6 wt% 3.1 wt% 5.8 wt% |
2000—day 28 4000—day 28 104—day 28 |
[54] |
| CP-Ti | 1 | CA, Na2HPO4, and 0.0025 M Ag-A | 380 | - | 5 | Flake-like morphology with regional Ag particles of <200 nm | Ti, anatase, rutile, HA, and CaTiO3 |
4.6 wt% | - | [55] |
| CP-Ti | 3 | 20.5 g/L CA, 7.2 G/L Na2HPO4, and (0.0005, 0.001, and 0.002) M Ag-A | 400 | - | 5 | Micro-porous structures with Ag NPs surrounding micro-pores | Ti, anatase, rutile, HA, and CaTiO3 |
1.14 wt% | - | [56] |
| Ti6Al4V | 1 | 20.5 g/L CA, 7.2 g/L Na2HPO4, and 0.001 M Ag-A | 400 | - | 5 | Micro-porous structures with Ag NPs of <100 nm surrounding micro-pores | Ti, anatase, rutile, HA, and CaTiO3 | 0.7 wt% | 1500—day 14 | [57] |
| Ti6Al4V | 2 | CA, β-GP and (0.1 and 0.4) g/L AgNO3 | 400 | - | 5 | Granular and needle-like morphology with Ag NPs of 20–30 nm | Ti, anatase, rutile, HA, and CaTiO3 | 0.6 wt% 2.1 wt% |
2500—day 14 8000—day 14 |
[58] |
| Ti-29Nb-13Ta-4.6Zr | 2 | 0.15 M CA, 0.1 M Ca-GP, and (0.0005 and 0.0025) M AgNO3 | - | 2.51 | 10 | Porous structures (<10 µm) |
- | 0.01 wt% 0.01 wt% |
- | [59] |
| CP-Ti | 3 | 0.1 M KOH, 0.015 M K4P2O7, and (0.1, 0.3 and 0.5) g/L Ag NPs | - | 10 | 5 | Micro-porous structures with Ag NPs of <20 nm (3–7.5 µm) | - | 0.53 at% 0.69 at% 0.80 at% |
12.2—day 1 22.7—day 1 28.8—day 1 |
[60] |
| CP-Ti | 1 | 0.3 M CA, 0.02 M GP, and 0.62 g/L Ag NPs | 290 | - | 10 | Porous structures with volcano top-like micro-pores | Ti, anatase, and rutile | 1.07 at% | - | [61] |
| CP-Ti | 1 | 0.3 M CA, 0.02 M GP, and 0.62 g/L Ag NPs | 290 | - | 10 | Porous structures with Ag NPs of <100 nm | Ti, anatase, and rutile | - | - | [62] |
| Ti6Al4V | 1 | Pure water and AgPURETM W10 nanosilver suspension | - | 20 | 0.5 | Flake-like morphology with Ag particles of <200 nm | - | 3.6 at% | - | [63] |
| Ti6Al4V | 2 | 0.2 M CA, 0.02 M β-GP, and (0.005 and 0.05) g/L Ag NPs | 387 ± 3 385 ± 2 |
8 | 3 | Porous structures with volcano top-like micro-pores (<3 µm) | Ti, rutile, and HA | <0.1 wt% <0.1 wt% |
- | [64] |
| CP-Ti | 3 | 2.0 g/L NaH2PO4·2H2O, 5.0 g/L CA, and 0.1, 0.5, and 0.8 g/L Ag-A | 500 | - | 5 | Porous structures uniformly covering surface | Ti, anatase, rutile, HA, CaTiO3 | 0.8 at% 1.5 at% 2.2 at% |
264—day 7 813—day 7 1110—day 7 |
[65] |
| CP-Ti | 2 | NTA, Ca(OH)2, and 180 mg/L Ag NPs | 250–300 | - | 5 | Rough, thick oxide layer with a highly porous structure |
- | 0.3 wt% 0.7 wt% |
- | [66] |
Ag-A: silver acetate, CA: calcium acetate, Ca-GP: calcium glycerophosphate, GP: glycerophosphate, HA: hydroxyapatite, KOH: potassium hydroxide, NPs: nanoparticles, NTA: nitrilotriacetic acid, SrA: strontium acetate, TCP: tricalcium phosphate.