Fluorescence Resonance Energy Transfer-Based Wash-Free Bacterial Imaging and Antibacterial Application Using a Cationic Conjugated Polyelectrolyte

• DOI: 10.1021/acsami.8b07516
• Publication Date: 2018-07-27T14:45:56Z
• Authors: Nehal Zehra; Deepanjalee Dutta; Akhtar Hussain Malik; Siddhartha Sankar...; Parameswar Krishn...
• Keywords: Cationic polymerization

The increase in bacterial infection and antibiotic resistance has posed a severe threat to the human health. This warranted an imperative demand for development of new effective bactericidal material eradicate antibiotic-resistant pathogenic bacteria. In this work, we report wash-free imaging Staphylococcus aureus (Gram-positive) Escherichia coli (Gram-negative) bacteria using cationic conjugated polyelectrolyte[9,9-bis(6′-methylimidazoliumbromide)hexyl-fluorene-co-4,7-(2,1,3-benzothiadiazole)] (PFBT-MI) based on aggregation-induced fluorescence resonance energy transfer (FRET). Cationic imidazolium group strapped polymer side chain not only increases its solubility water but also helps binding with negatively charged membrane via electrostatic interactions turn bright yellow emission. change color polyelectrolyte presence could be visualized very easily naked eyes under UV lamp (365 nm). Furthermore, antibacterial activity PFBT-MI against both S. E. was observed because amphiphilic nature which is due ionic functionality backbone that can intercalate proficiently into membrane, disrupts integrity thus results toxicity. Morphologically, damage perceived field emission scanning electron microscopy (FESEM) images, clearly indicated disruption cell upon exposure PFBT-MI. acts as agent, minimum inhibitory concentration (MIC) (MBC) value (30 μM or 23.7 μg/mL) (60 47.7 (100 79 μg/mL), respectively. Moreover, shows less cytotoxicity mammalian cells at greater than MIC.