Host defense peptide mimicking antimicrobial amino acid polymers and beyond: Design, synthesis and biomedical applications

Drug delivery systems for enhanced tumour treatment by eliminating intra-tumoral bacteria

“…76–78 The use of antimicrobial nanomaterials as stimuli-responsive carriers can synergize with anticancer drugs to work together. 79 Among them, pH-responsive controlled release drug delivery systems are common. In recent years, Wei Ha and his colleagues utilized antimicrobial metal–phenol nanosheets (Cu–TA) formed using copper ions and tannic acid as a nanocarrier for delivering stimuli-responsive anticancer drugs and improved the loading efficiency through chelation between epirubicin hydrochloride (EPI) and copper ions.…”

Regulation of Hydrophobic Structures of Antibacterial Guanidinium-Based Amphiphilic Polymers for Subcutaneous Implant Applications

“…The product was identified by 1 H NMR and denoted as MAGH. 1 H NMR (D 2 O, 298 K, 400 MHz): δ (ppm) = 5.97 (s, −C�C−H, 1H), 5.80 (s, −C�C−H, 1H), 1.94 (s, −CH 3 , 3H).…”

“…Antimicrobial peptides (AMPs) as the substance in innate immune defense system show broad-spectrum antibacterial activity . However, due to the limitation of difficult synthesis and the relatively high cost of the AMPs, synthetic mimics of AMPs have been extensively studied and widely used as disinfectants in the biomedical field. , In recent years, researchers have explored the structure of AMPs and simulated them to design amphiphilic AMP mimics with cationic and hydrophobic components. − Among the cationic groups, such as quaternary ammonium, phosphonium, and sulfonium, guanidine groups with a planar array of rigid hydrogen bond donors, which can form efficient bidentate hydrogen bonds with the phospholipids of the bacterial cell, have aroused considerable attention in antibacterial polymer synthesis and materials sciences. , Meanwhile, guanidine-based arginine constitutes the cell membrane-penetrating peptide and corresponds to strong cell-lytic behavior, which can enhance the damage to bacterial cell membranes .…”

“…Antimicrobial peptides (AMPs) as the substance in innate immune defense system show broad-spectrum antibacterial activity. 1 However, due to the limitation of difficult synthesis and the relatively high cost of the AMPs, synthetic mimics of AMPs have been extensively studied and widely used as disinfectants in the biomedical field. 2,3 In recent years, researchers have explored the structure of AMPs and simulated them to design amphiphilic AMP mimics with cationic and hydrophobic components.…”

Peptide-Mimicking Poly(2-oxazoline)s Possessing Potent Antifungal Activity and BBB Penetrating Property to Treat Invasive Infections and Meningitis

“…Current challenges for effective treatment of invasive fungal infections and meningitis majorly lie in two aspects: (1) developing potent and low-toxic antifungal agents that also have low susceptibility to antifungal resistance and (2) enhancing the BBB penetrating property of antifungal agents simultaneously. Although tremendous efforts have been devoted to develop potent and low-toxic antifungal agents, ,− the progress is slow because of the high similarity between fungi and mammalian cells that are both eukaryotes, in sharp contrast to the development of selective antibacterial agents including antimicrobial peptides and their mimics. − Many strategies have been explored to break the constraint of the BBB, − among which drug modification with cell-penetrating peptides (CPPs) has been considered a promising strategy, using CPPs such as TAT (YGRKKRRQRRR) peptide and polyarginines. − However, the success of this strategy in developing potent antimicrobial agents for meningitis is hindered by the complexity of the conjugation reaction, the difficult purification of conjugates, and the reduction of conjugates’ antifungal potency. Therefore, an effective antifungal design strategy is urgently needed to meet the requirement of potent antifungal activity, high selectivity, and BBB penetrating property simultaneously.…”