TY - JOUR
T1 - Bacterial killing by light-triggered release of silver from biomimetic metal nanorods
AU - Black, Kvar C.L.
AU - Sileika, Tadas S.
AU - Yi, Ji
AU - Zhang, Ran
AU - Rivera, José G.
AU - Messersmith, Phillip B.
PY - 2014/1/15
Y1 - 2014/1/15
N2 - Illumination of noble metal nanoparticles at the plasmon resonance causes substantial heat generation, and the transient and highly localized temperature increases that result from this energy conversion can be exploited for photothermal therapy by plasmonically heating gold nanorods (NRs) bound to cell surfaces. Here, plasmonic heating is used for the first time to locally release silver from gold core/silver shell (Au@Ag) NRs targeted to bacterial cell walls. A novel biomimetic method of preparing Au@Ag core-shell NRs is employed, involving deposition of a thin organic polydopamine (PD) primer onto Au NR surfaces, followed by spontaneous electroless silver metallization, and conjugation of antibacterial antibodies and passivating polymers for targeting to gram-negative and gram-positive bacteria. Dramatic cytotoxicity of S. epidermidis and E. coli cells targeted with Au@Ag NRs is observed upon exposure to light as a result of the combined antibacterial effects of plasmonic heating and silver release. The antibacterial effect is much greater than with either plasmonic heating or silver alone, implying a strong therapeutic synergy between cell-targeted plasmonic heating and the associated silver release upon irradiation. The findings suggest a potential antibacterial use of Au@Ag NRs when coupled with light irradiation, which has not been previously described. Bimetallic gold core/silver shell nanorods are formed with polydopamine-based biomimetic synthesis and target bacteria with antibody functionalization. Light irradiation of the nanorods causes plasmonic heating and release of silver, which efficiently kills E. coli and S. epidermidis bacteria with a novel multifunctional therapeutic strategy.
AB - Illumination of noble metal nanoparticles at the plasmon resonance causes substantial heat generation, and the transient and highly localized temperature increases that result from this energy conversion can be exploited for photothermal therapy by plasmonically heating gold nanorods (NRs) bound to cell surfaces. Here, plasmonic heating is used for the first time to locally release silver from gold core/silver shell (Au@Ag) NRs targeted to bacterial cell walls. A novel biomimetic method of preparing Au@Ag core-shell NRs is employed, involving deposition of a thin organic polydopamine (PD) primer onto Au NR surfaces, followed by spontaneous electroless silver metallization, and conjugation of antibacterial antibodies and passivating polymers for targeting to gram-negative and gram-positive bacteria. Dramatic cytotoxicity of S. epidermidis and E. coli cells targeted with Au@Ag NRs is observed upon exposure to light as a result of the combined antibacterial effects of plasmonic heating and silver release. The antibacterial effect is much greater than with either plasmonic heating or silver alone, implying a strong therapeutic synergy between cell-targeted plasmonic heating and the associated silver release upon irradiation. The findings suggest a potential antibacterial use of Au@Ag NRs when coupled with light irradiation, which has not been previously described. Bimetallic gold core/silver shell nanorods are formed with polydopamine-based biomimetic synthesis and target bacteria with antibody functionalization. Light irradiation of the nanorods causes plasmonic heating and release of silver, which efficiently kills E. coli and S. epidermidis bacteria with a novel multifunctional therapeutic strategy.
KW - antibacterial silver release
KW - antibodies
KW - melanin-mimetic polydopamine
KW - metal nanorods
KW - plasmonic heating
UR - http://www.scopus.com/inward/record.url?scp=84891869701&partnerID=8YFLogxK
U2 - 10.1002/smll.201301283
DO - 10.1002/smll.201301283
M3 - Article
C2 - 23847147
AN - SCOPUS:84891869701
VL - 10
SP - 169
EP - 178
JO - Small
JF - Small
SN - 1613-6810
IS - 1
ER -