Table 1.
Methods, synthesis and characterizations of silver nanoparticles, and antibacterial activity evaluation of selected publications from the 2015–2018 period.
| Stabilizer | NPs Size (nm) | NPs Shape | Stock Suspension Concentration or Mass | Zeta Potential (mV) * | Comment | Bacteria | Bacteria Origin | Protocol | Culture Media | Reference |
|---|---|---|---|---|---|---|---|---|---|---|
| “Naked” | 19.5 ± 7.7 | Nano-sphere | N/A | −18.0 ± 0.6 (in culture media) |
NaBH4 + AgNO3 in presence of ultrasonication |
E. faecalis
S. aureus S. epidermidis B. subtilis E. coli S. typhimurium S. enterica |
KCCM 13807 KCTC 1916 KCTC 1971 KCTC 1021 KCTC 1682 KCCM 40253 KACC 10763 |
Kirby-Bauer method Microdilution method MIC90 |
Mueller Hinton Agar Luria Bertani |
[3] |
| 10 | Nano-flake | 50 ppm | N/A | Axonnite Silver suspended in demineralized water |
A. baumannii (n = 17) A. baumannii A. nosocomialis (n = 10) |
Clinical isolates ATCC 1906 Clinical isolates |
Microdilution method | N/A | [4] | |
| 10 20 40 |
Nano-sphere | N/A | N/A | Vapor nucleation in N2 gas | E. coli | N/A | Kirby-Bauer method | Mueller Hinton 2 Agar | [5] | |
| 55.6 ± 2.9 (DLS) | Nanosphere | 8.53 mg | −51.5 ± 2.5 | Electrochemically synthesized |
P. aeruginosa (n = 3) S. maltophilia (n = 3) B. cepacia (n = 3) S. aureus (n = 3) |
Clinical isolates | Kirby-Bauer method Microdilution method TKA |
Mueller Hinton Cation-Adjusted |
[6] | |
| 2–5 (70–75% TEM) |
Nano-sphere | 50 mg/kg | +9.2 | Nano-Tech (Warsaw, Poland) | L. monocytogenes | PCM 2191 | Microdilution method | Tryptone Soy yeast extract broth | [7] | |
| 23.6 (TEM) 57.8 (DLS) |
Nano-sphere | N/A | −28.3 (N/A) |
Nanoleader (Korea) |
E. coli (K-12) |
KCTC 1116 | Growth Curves | Luria Bertani | [8] | |
| 10 | Nano-sphere | 1 mg/mL | N/A | Sisco Research lab. |
S. aureus S. aureus (n = 30) |
ATCC 25923 Clinical isolates |
Agar Well diffusion method Microdilution method |
Mueller Hinton Agar Luria Bertani |
[9] | |
| “Naked” | 40 (TEM) | Nano-sphere | N/A | N/A | AgNO3 + NaBH4 |
S. aureus
B. cereus P. aeruginosa K. pneumoniae E. coli |
N/A | Agar Well diffusion method | Mueller Hinton Agar | [10] |
| Unknown “Naked” | 35 27.2 |
Nano-sphere | 20 µg/mL N/A |
N/A | Sigma Aldrich (Dorset UK) Laser generated |
E. coli (K-12) |
JM 109 | Agar Well diffusion method | Mueller Hinton | [11] |
| Citrate | 23 ± 2 (TEM) | Nano-sphere | 2 mM | N/A | Citrate BioPure™ Silver, Nanocomposix (San Diego, CA, USA) |
L. monocytogenes (n = 20) L. monocytogenes |
Clinical isolates | Colony Forming Units | Mueller Hinton | [12] |
| 6.0–28.2 (XRD) | N/A | −28.2 to −32.0 | Plasma discharge |
S. aureus
E. coli |
ATCC 25923 ATCC 35218 |
Kirby-Bauer method | Nutrient Agar | [13] | ||
| 2.3 ± 0.5 12.5 ± 2.2 32.4 ± 6.5 (TEM) |
Nano-sphere | N/A1 | N/A1 | NaBH4 + AgNO3 + sodium citrate |
S. aureus
E. coli |
ATCC 35696 ATCC 23282 |
Microdilution method Kirby-Bauer method Growth Curves |
Broth medium | [14] | |
| 40–50 20 × 20–90 |
Nano-sphere Nano-rod |
N/A | −28.8 −23.5 |
Citrate thermal reduction method |
S. aureus
B. subtilis P. aeruginosa K. pneumoniae E. coli |
ATCC 25923 AST5-2 AL2-14B AWD5 ATCC 25922 |
Microdilution method Kirby-Bauer method TKA |
Nutrient Agar | [15] | |
| 20.1 ± 4.4 (TEM) 49.3 ± 5.7 (DLS) |
Nano-sphere | N/A | −19.2 ± 0.7 | Citrate thermal reduction method |
E. coli
S. aureus L. bulgaricus L. casei |
ATCC 25922 ATCC 25923 CGMCC 1.6970 CGMCC 1.2435 |
TKA | Luria Bertani Tryptone Soy MRS |
[16] | |
| 10–40 (TEM) | Sharp-tipped triangular, truncated triangular, nanoprisms, decahedra, tetrahedra | N/A | N/A | Photochemical synthesis: 4.76 ± 3.88 nm silver seed nanoparticles (AgNO3 + citrate + NaBH4) + 40 W blue LEDs (Hongke Lighting kem = 455–475 nm) {111} facets |
E. coli | ATCC 25922 | Growth Curves | Luria Bertani | [17] | |
| Citrate | 20 ± 9 25 ± 3 11 ± 6 (TEM) |
Nano-sphere | N/A | −26.37 −37.95 −28.23 (H2O + salts) |
AgNO3 + citrate + NaBH4 | S. aureus | ATCC 25923 | Agar Well diffusion method | Nutrient Agar | [18] |
| 42–58 (TEM) | Nano-sphere | N/A | N/A | AgNO3 + citrate + NaBH4; polydisperse; XRD11: intense reflection at (111) |
S. aureus
S. pyogenes S. typhi P. aeruginosa |
N/A | Kirby-Bauer method | Tryptone Soy | [19] | |
| 15 18 30 30 (DLS) |
Nano-sphere | N/A | −38.8 −30.7 −38.5 −42.2 (N/A) |
AgNO3 + Citrate + NaBH4 |
E. coli
B. subtilis |
N/A | Kirby-Bauer method | Nutrient Agar | [20] | |
| GSH13 | 10–50 | Nano-sphere | 0.197 mg/mL | N/A | AgBF4 + NaBH4 + glutathione |
C. jejuni (n = 22) C. coli (n = 18) C. jejuni |
Animal or Human clinical isolates NCTC 11168 |
Microdilution method | Brucella Mueller Hinton |
[21] |
| D-xylose L-arabinose D-ribose D-glucose D-galactose D-mannose D-lactose D-xylose |
33 30 39 25 28 25 15 18 |
Nano-sphere | N/A | N/A |
E. coli Klebsiella spp. |
N/A | N/A | N/A | [22] | |
| L-fucose | 10.15 ± 3.37 (TEM) | Nano-sphere | N/A | −65.4 −17.7 |
AgNO3 + NaBH4 + sodium citrate + mercaptopropionic acid, then L-fucose |
P. aeruginosa (PAO1) |
N/A | Microdilution method | Luria Bertani without Chloride ions | [23] |
| PEG | 15.8 ± 2.2 (TEM) | Nano-sphere | N/A | −17.2 ± 2.1 | AgNO3 + EG/PEG |
S. aureus
P. aeruginosa S. enterica E. coli |
ATCC 6538 ATCC 15442 ATCC 10708 ATCC 11229 |
Microdilution method | Mueller Hinton | [24] |
| PC | 3.3 ± 0.9 4.9 ± 2.9 (TEM) |
Nano-sphere | N/A | N/A | Zwitterionic Protection: AgNO3 + NaBH4 + PC-SH |
E. coli
S. aureus |
OW6 Mu50 |
Growth curves | Todd Hewitt broth | [25] |
| PVA | 31 (SEM; TEM: 26) 24 (SEM) 19 (SEM) 14 (SEM; TEM: 10) |
Nano-sphere | N/A | N/A | PVA + AgNO3 + NaBH4 (pH = 6; 8; 10; 12, respectively) |
E. coli Pseudomonas sp. |
N/A | Kirby-Bauer method | Nutrient Agar | [26] |
| PVP/citrate | 50–60 70–80 |
Semi-triangular and truncated triangular silver nanoparticles + few nano-sphere Triangular silver nanoparticles with sharp corner |
N/A | N/A | Citrate + AgNO3 + NaBH4 + PVP + visible-light halogen lamp (50 and 100 W, respectively); bigger nanoparticles (>100 nm) obtained with visible-light halogen lamps with higher intensities | E. coli | N/A | Colony Forming Units | Nutrient Agar | [27] |
| PVP20 | 14.0 ± 0.3 (TEM) | Nano-sphere | 1 mg/mL | −27.3 | Nanocomposix, OECD standard BioPure, PVP20 40kDa |
E. coli (K-12) B. subtilis |
MG1655 ATCC 6051 |
Growth curves | Tryptone Soy | [28] |
| 5 20 |
Nano-sphere | 1 mg/mL 2 mg/mL |
N/A | Shanghai Institute of Fine Chemical Materials (China) |
E. coli
P. aeruginosa S. aureus S. epidermidis |
ATCC 8739 ATCC 9027 ATCC 6538 ATCC 12228 |
Poisoned Food Technique | Mueller Hinton | [29] | |
| 8 29 (TEM) |
Nano-sphere | N/A | −22.36 −37.82 |
PVP + ethylene glycol + AgNO3; redispersed in water |
A. hydrophila
P. putida E. coli B. subtilis S. aureus |
4AK4 KT2442 Trans 1-T1 ATCC 28357 N/A |
Kirby-Bauer method Microdilution method |
N/A Mueller Hinton |
[30] | |
| 15.6 (TEM) | Nano-sphere | N/A | N/A | PVP + AgNO3 + NaBH4 in water; polydisperse |
Citrobacter sp. Enterococcus sp. |
N/A | Colony Forming Units | N/A | [31] | |
| 3–34 (TEM) | Nano-sphere | N/A | N/A | AgNO3 + Ethanol + PVP (55000 molecular mass) in water |
S. aureus PTCC No. 1112 E. coli PTCC No. 1330 |
ATCC 6537 ATCC 8739 |
N/A | Mueller Hinton | [32] | |
| 10–15 (TEM) | Nano-sphere | N/A | N/A | AgNO3 + PVP (k30; Mw. 40000) + hydrazine; influence of AgNO3, PVP and hydrazine concentrations |
E. coli
S. aureus |
ATCC 25922 ATCC 25923 |
Kirby-Bauer method | Nutrient Agar | [33] | |
| 60 ± 15 55 ± 10 60 × 2000–4000 |
Nano-sphere Nano-cube, right bipyramids Nanowire |
N/A | N/A | AgNO3 + PVP (k30) + ethylene glycol + NaCl (0. 1, and 5 mg, respectively) | E. coli | ATCC 25922 | Growth curves Microdilution method |
Luria Bertani | [34] | |
| 20.6 ± 3.1 | Nano-sphere | 1 mg/mL | −35 | Nanocomposix (San Diego, CA, USA) |
C. jejuni (n = 4) C. jejuni Salmonella spp. (n = 5) |
Chicken isolates NCTC 11168 Chicken isolates |
Microdilution method | Mueller Hinton Luria Bertani |
[35] | |
| PVP Glycerol |
31.2 (TEM) 46.5 (DLS) |
Nano-sphere | N/A | +18.7 (N/A) |
AgNO3 + PVP or glycerol + sodium citrate (NH4OH, pH = 8) |
C. sakazakii | ATCC 29544 ATCC BAA894 ATCC 29004 ATCC 12868 |
Microdilution method Oxford cup method |
Luria Bertani | [36] |
| Oleylamine | 10 (TEM) | Nano-sphere | N/A | −7.11 | ColdStones Tech. (Suzhou, China) | B. subtilis | ATCC 6633 | Growth curves | Luria Bertani | [37] |
| Casein | 12.5 ± 4 (TEM) 50.0 ± 0.7 (DLS) |
Nano-sphere | N/A | −26.6 ± 1.7 {in 3-(N-morpholini) propanesulfonic acid-(hydroxy-methanyl) aminomethane} |
Lab. Argenol S. L. (Zaragoza, Spain) |
E. coli
P. aeruginosa |
MC 1061 DS 10-129 |
Bioluminescence inhibition assay | Luria Bertani | [38] |
| Sericin | 3.78 ± 1.14 (TEM) | Nano-sphere | N/A | N/A | Silk sericin protein + AgNO3 + NaBH4 |
S. aureus
E. coli |
ATCC 25923 ATCC 25922 |
Cell counting (FCM) |
Nutrient medium | [39] |
| Thioacetic acid Propionic acid |
20–25 30–35 |
Nano-sphere | N/A | N/A | Thioacetic or propionic acid + silver acetate + sodium carbonate (US20120100372A1) |
S aureus
S. epidermidis A. baumannii P. aeruginosa |
ATCC 25923 ATCC 35984 ATCC 19606 ATCC 27853 |
Microdilution method | Mueller Hinton | [40] |
| Lipoid acid | 2.0 ± 0.5 (TEM) | Nano-sphere | N/A | N/A | dihydrolipoic acid + NaOH + AgNO3 + NaBH4 |
S. aureus
E. coli E. coli |
N/A DH5α DSM4230 |
Growth curves | Luria Bertani | [41] |
| PEG EDTA PVP PVA |
44 39 35 31 (SEM) |
Nano-sphere | N/A1 | −17.5 −23.0 −41.0 −47.0 |
PEG, EDTA, PVP or PVA + AgNO3 + NaOH + NaBH4 in water |
E. coli Pseudomonas spp. |
N/A | Kirby-Bauer method | Nutrient Agar | [42] |
| “Naked” Unknown |
7.5 10.1 (TEM) |
Nano-sphere | 9.7 × 10−8 mol/L 4 × 10−8 mol/L |
−38.0 0.0 |
AgNO3 + NaBH4 Rice starch + AgNO3 |
S. aureus
S. mutans S. pyogenes E. coli P. vulgaris |
ATCC 29737 ATCC 35668 ATCC 8668 ATCC 15224 ATCC 7829 |
Agar Well diffusion method Microdilution method |
Brain Heart Infusion Mueller Hinton |
[43] |
| PVA Citrate Citrate |
10 nm (SEM) 40 nm (SEM) 60 nm |
Nano-sphere | N/A N/A 20 μg/L |
−17.0 −48.4 N/A |
Chitosan-Ag NPs also prepared and tested (Sigma Aldrich) |
A. baumanni (n = 17) P. aeruginosa (n = 13) Enterobacteriaceae (n = 21) S. maltophilia (n = 2) S. aureus (n = 13) S. aureus S. epidermidis Enterococcus sp. (n = 14) |
Clinical isolates Clinical isolates Clinical isolates Clinical isolates Clinical isolates ATCC 29213 INCQS 198 Clinical isolates |
Agar Well diffusion method Microdilution method Time kill assay |
Mueller Hinton Mueller Hinton Cation Adjusted Tryptone Soy Mueller Hinton Cation Adjusted |
[44] |
| Cysteine PVP |
7.6 ± 1.5 7.7 ± 1.6 (TEM) |
Nano-sphere | N/A | N/A | AgNO3 + NaBH4 + L-cysteine AgNO3 + KOH + PVP (Mw 8000) + NaBH4 |
S. aureus
E. coli P. aeruginosa |
ATCC 29213 ATCC 23716 ATCC 25619 |
Microdilution method | Mueller Hinton Cation Adjusted | [45] |
| Citrate MPA MHA MPS |
10.2 ± 2.3 10.2 ± 2.5 10.2 ± 2.2 9.9 ± 2.0 |
Nano-sphere | N/A | −47.4 −34.5 −29.1 −32.6 |
Citrate + tannic acid + AgNO3 Citrate-Ag NPs + mercaptopropionic acid (ligand exchange) Citrate-Ag NPs + mercaptohexanoic acid (ligand exchange) Citrate-Ag NPs + mercaptopropionic sulfonic acid (ligand exchange) |
E. coli | MG 1655 | Growth curves | Luria Bertani | [46] |
| Citrate PVP PEG |
40 (TEM; 10–70) | Nano-sphere Triangular silver nanoparticles with rounded edges Hexagonal silver NPs |
N/A | N/A | AgNO3 + citrate PVP (Mw = 25000) + AgNO3 + citrate + H2O2 + NaBH4 PEG (2000) + NaOH + AgNO3 |
E. coli | DH5α | Agar Well diffusion method Growth curves |
Luria Bertani | [47] |
| Lipoid acid PEG “Naked” |
9.5 ± 1.9 (TEM) 9.8 ± 2.0 11.2 ± 2.1 |
Nano-sphere | N/A | −28.6 (Serum free culture medium) −10 (Serum free culture medium) −33.9 (Serum free culture medium) |
Nanocomposix, Europe Nanocomposix, Europe Also Tannic acid-NPs US research (Nanomaterilas (Houston, TX, USA) |
Actinomyces (n = 1) Bacteroides (n = 4) Bacteroides fragilis Bifidobacterium (n = 1) Bifidobacterium breve Finegoldia (n = 2) Fusobacterium (n = 4) Fusobacterium nucleatum Parabacteroides (n = 1) Parvimonas (n = 2) Peptostreptococcus (n = 1) Peptostreptococcus anaerobius Porphyromonas (n = 3) Porphyromonas levii Prevotella (n = 5) Prevotella loescheii Propionibacterium (n = 2) Tannerella (n = 1) S. aureus S. aureus S. aureus S. epidermidis S. mutans |
Clinical isolates Clinical isolates ATCC 25285 Clinical isolates ATCC 15700 Clinical isolates Clinical isolates ATCC 25585 Clinical isolates Clinical isolates Clinical isolates ATCC 25286 Clinical isolates ATCC 29147 Clinical isolates ATCC 15930 Clinical isolates Clinical isolates ATCC 25923 ATCC 6538 ATTC 6538P ATCC 14990 ATCC 29175 |
Plate dilution method Microdilution method |
Brucella agar supplemented Mueller Hinton |
[48] |
| Citrate HH SHSH SHST |
15 ± 4 13 ± 2 13 ± 4 10 ± 6 (TEM) |
Nano-sphere | 290 mg/L 290 mg/L 330 mg/L 330 mg/L |
−39.8 ± 0.74 (H2O + NaCl) −34.0 ± 1.97 (H2O + NaCl) −34.4 ± 2.03 (H2O + NaCl) −35.9 ± 1.09 (H2O + NaCl) |
AgNO3 + Citrate + NaBH4 Hydroxylamine hypochlorite + NaOH + AgNO3 Sodium hypophosphite + sodium hexametaphosphate + AgNO2 Sodium hypophosphite + sodium hexametaphosphate + sodium tripolyphosphate + AgNO2 |
E. coli (K-12) E. coli |
ATCC 10798 ER2566 |
Microdilution method | Mueller Hinton | [49] |
| Starch | 8 ± 4 (TEM) | Nano-sphere | N/A | N/A | AgNO3 + NaBH4 + (C6H10O5)n |
S. aureus
E. coli |
N/A | Kirby-Bauer method | Nutrient agar | [50] |
| AOT | 20 50 |
“Nano-sphere” | N/A | N/A | Bis(2-ethylhexyl) sulfosuccinate + AgNO3 + ascorbic acid |
E. coli
S. aureus |
N/A | Microdilution method | Luria Bertani | [51] |
N/A: not available; KCCM: Korean Culture Center of Microorganisms; KCTC: Korean Collection of Type Cultures; KACC: Korean Agriculture Culture Collection; MIC: minimal inhibitory concentration; ATCC: American Type Culture Collection; DLS: dynamic light scattering; TKA: Time Kill Assay; TEM: transmission electron microscope; PCM: Polish Collection of Microorganisms; XRD: X-ray diffraction; CGMCC: China General Microbiological Culture Collection Center; MRS: deMan, Rogosa and Sharpe medium; GSH: glutathione; NCTC: National Collection of Type Culture; PEG: polyethylene glycol; CTAB: cetyl-trimethyl ammonium bromide; NTA: nanoparticle tracking analysis; PC: phosphorylcholine; PVA: polyvinyl alcohol; SEM: scanning electron microscope; PVP: polyvinylpyrrolidone; ATCC: American Type Culture Collection; EDTA: ethylenediaminetetraacetic acid; FCM: flow cytometry; MPA: mercaptopropionic acid; MHA: mercaptohexanoic acid; MPS: mercaptopropionic sulfonic acid; HH: Hydroxylamine hypochlorite; SHSH: Sodium hypophosphite and sodium hexametaphosphate; SHST: sodium hypophosphite, sodium hexametaphosphate and sodium tripolyphosphate; AOT: Bis(2-ethylhexyl) sulfosuccinate; * in aqueous medium if not specified.