Synthesis & Antimicrobial Efficacy of Magnetic Silica - PowerPoint PPT Presentation

10 th U.S.-Korea Nano Forum, Boston, MA, Oct 15-16, 2013 Synthesis & Antimicrobial Efficacy of Magnetic Silica Microspheres Decorated with AgNPs Kyoungja Woo

Motiv ivatio ion o n of the P e Project Nano C Convergent Materi erials T s Tech. Need eds s for V Virus s Rem emoval Sy Syst stem (Air, r, W Water) er) SOCIAL D DEMAND OUTBREAKS OF VIRAL INFECTION !

AgNP NP int nterac actio ion w n with b bac acterial ial c cel ells AgNPs The smaller, the better 1) Release Ag + and generate ROS 2) Interact with membrane protein 3) Accumulate in the cell membrane 4) Enter into the cell J. Nanopart. Res. (2010) 12:1531

AgNP NP inter eraction w with m h microb obial al m membranes anes AgNP(~12 nm) & E. Coli AgNP(<10 nm) & HIV-I b d Degradation of the membrane The AgNPs bind to the gp120 knobs Structure (cysteine location) of HIV virus Journal of Colloid and Interface Science 2004, 275, 177 Journal of Nanobiotechnology 2005, 3:6

Major challenges in practical utilization of AgNPs 1. Aggregation of AgNPs 2. Environmental release of AgNPs * The smaller, the better?

Organi anic P Polymer er-AgN gNP Composit ite Polysulfone ultrafiltration membrane impregnated with AgNP (Membrane fabrication: 1 15% PS PSf, 10% 10% P PVP, 75% 75% N NMP, , 0. 0.9% AgNP) without AgNP with AgNP After filtration of 0.4 L/cm 2 , 10% AgNP loss ! Water Research 2009, 43, 715

Inorgani anic Super erparam amag agnet etic AgNP NP Composit ite ▪ Magne gnetic h hybr brid c d colloid d d decor orated d with AgN gNP (AgN gNP@MHC HC)

Inorgani anic Super erparam amag agnet etic AgNP@ P@MH MHC S. Coverage: 8.8% 25% 18%

Inorgani anic Super erparam amag agnet etic Ag/Au@M @MHC

XPS a PS analysi sis o s of A Ag/Ag@MH MHC nAg30@MHC Ag 3d 5/2 , 3d 3/2 N 1s AP@MHC + Ag + AP@MHC + + + + AP + + + + Fe O + 3 4 + + Silica

Cat atal alytic P Property o of A Ag/Au@M @MHC ▪ Repe peatedl dly u y usable noble m e met etal nanoc nocatalyst yst com ompo posi site Ag/Au@MHC k a = 0.095/min TOF(nAg/Au@MHC) = 3.8 × 10 -3 /s TOF(chitosan-AgNP 5nm ) = 0.97 × 10 -3 /s Sci. Rep. 2013, 3, 1497, Woo

Ant ntim imicr icrobia ial ef effec ects o of AgNP@MHC E. Coli li CN13 Bacteriophage MS2

AgNP@MHC bites away bacteria E.coli CN13+Ag30@MHC E.coli CN13+Ag30@MHC E.coli CN13+Ag30@MHC E.coli CN13 @30 min @60 min as-prepared

AgNP@MHC chemisorbs viruses (Bacteriophage MS2)

Influenza viral HA structure (interactions at the dimer interface) Asn228 Arg226 His181 Tyr230 Asp94 Glu213 Glu213 Asp94 Tyr230 His181 Arg226 Asn228 from Prof. Kyunghyun Kim in Korea University

Mechani nist stic study f udy for antimicrobi bial e effects o s of AgN gNP (30 n nm) m) (C) (A) (B) 1 h 1 h 1 d 1 d

Scale-up synthesis for practical application TEOS

Acknowledgment Fund: Ministry of Science, ICT & Future Planning through NRF of Korea (GNT program), KIST People: Dr. Hye Hun Park (KIST), Ms. Mihwa Seo (KIST), Dr. Jae-Pyoung Ahn (KIST), Mr. SungJun Park (SNU), Prof. GwangPyo Ko (SNU) Mr. Yoonhaeng Cho (Yonsei U.) Prof. Jeongho Hwang (Yonsei U.)

Thank you !