title: Synthesis of Self-Assembled Spermidine-Carbon Quantum Dots Effective against Multidrug-Resistant Bacteria.
abstract: This study reports a two-step method to synthesize spermidine-capped fluorescent carbon quantum dots (Spd-CQDs) and their potential application as an antibacterial agent. Fluorescent carbon quantum dots (CQDs) are synthesized by pyrolysis of ammonium citrate in the solid state and then modified with spermidine by a simple heating treatment without a coupling agent. Spermidine, a naturally occurring polyamine, binds with DNA, lipids, and proteins involved in many important processes within organisms such as DNA stability, and cell growth, proliferation, and death. The antimicrobial activity of the as-synthesized Spd-CQDs (size ≈4.6 nm) has been tested against non-multidrug-resistant E. coli, S. aureus, B. subtilis, and P. aeruginosa bacteria and also multidrug-resistant bacteria, methicillin-resistant S. aureus (MRSA). The minimal inhibitory concentration value of Spd-CQDs is much lower (>25 000-fold) than that of spermidine, indicating their promising antibacterial characteristics. The mechanism of antibacterial activity is investigated, and the results indicate that Spd-CQDs cause significant damage to the bacterial membrane. In vitro cytotoxicity and hemolysis analyses reveal the high biocompatibility of Spd-CQDs. To demonstrate its practical application, in vitro MRSA-infected wound healing studies in rats have been conducted, which show faster healing, better epithelialization, and formation of collagen fibers when Spd-CQDs are used as a dressing material.
authors.affiliation: Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, 20224, Taiwan.
authors.forename: Yu-Jia
authors.initials: YJ
authors.lastname: Li
authors.affiliation: Department of Chemistry, Université de Montréal, Montréal, Québec, H3C 3J7, Canada.
authors.forename: Scott G
authors.initials: SG
authors.lastname: Harroun
authors.affiliation: National Laboratory Animal Center, Taipei, 11599, Taiwan.
authors.forename: Yu-Chia
authors.initials: YC
authors.lastname: Su
authors.affiliation: National Laboratory Animal Center, Taipei, 11599, Taiwan.
authors.forename: Chun-Fang
authors.initials: CF
authors.lastname: Huang
authors.affiliation: Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, 20224, Taiwan.
authors.forename: Binesh
authors.initials: B
authors.lastname: Unnikrishnan
authors.affiliation: Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, 20224, Taiwan. hanjia@ntou.edu.tw.
authors.forename: Han-Jia
authors.initials: HJ
authors.lastname: Lin
authors.affiliation: Department of Biotechnology, National Formosa University, Yunlin, 63208, Taiwan.
authors.forename: Chia-Hua
authors.initials: CH
authors.lastname: Lin
authors.affiliation: Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, 20224, Taiwan. huanging@ntou.edu.tw.|Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung, 20224, Taiwan. huanging@ntou.edu.tw.|School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan. huanging@ntou.edu.tw.
authors.forename: Chih-Ching
authors.initials: CC
authors.lastname: Huang
mesh_terms: D000072283:A549 Cells; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D002244:Carbon / Q000737:chemistry*; D019343:Citric Acid / Q000737:chemistry; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects*; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D061986:MCF-7 Cells; D008297:Male; D008826:Microbial Sensitivity Tests / Q000379:methods; D011073:Polyamines / Q000737:chemistry; D045663:Quantum Dots / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D013095:Spermidine / Q000737:chemistry* / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D011073:Polyamines; D000644:Quaternary Ammonium Compounds; D019343:Citric Acid; D002244:Carbon; C481046:ammonium citrate; D013095:Spermidine
keywords: antimicrobial drugs; carbon quantum dots; multidrug resistant bacteria; polyamines; wound healing