L histidine dihydrochloride

β-Glutamic acid hydrochloride and dimethyl sulfoxide (DMSO) were purchased from Fluka (Buchs, Switzerland). L-Histidine dihydrochloride, diethyl ether, DAPI (4′,6-diamidino-2-phenyindole, dilactate) and PBS were purchased from Sigma Co. (St Louis, MO). Poly(ethylene glycol) (PEG) diacrylate (Mn=258, density=1.11 g ml⁻¹) and branched polyethyleneimine (bPEI_25K, Mw=25,000) were purchased form Aldrich (Milwaukee, MI). Plasmid DNA of pCMV vector (pcDNA 3.1) as a null control was purchased from Invitrogen (Carlsbad, CA, USA). Plasmid DNAs of pGL3, pCMV-p53 and pKillerRed-mem were purchased from Promega (Madison, WI, USA), Clontech Laboratories (Mountain View, CA) and Evrogen JSC (Moscow, Russia), respectively. For the preparation of fluorescent-labelled plasmid DNA, pCMV-p53 and pKillerRed-mem stocks were labelled with fluorescein as a fluorescent dye using a Label IT Nucleic Acid Labeling Kit (Mirus Bio, Madison, WI).

Chitosan—low molecular weight, phosphate-buffered saline tablets, select yeast extract, tryptone, agar, Tween 80, and l-histidine dihydrochloride were purchased from Sigma-Aldrich; acetic acid, sodium chloride p.a., and n-hexane 99% p.a. from Penta Chemicals; sodium tripolyphosphate (TPP) from Acros Organics; ethanol 99.8% for UV/VIS spectroscopy, and glycerol anhydrous g. r. from Lach-Ner; curcumin 99.9% from Chromadex; Brain–Heart-Infusion broth (BHI, Hirn-Herz-Glucose-Bouillon für die Mikrobiologie) from Carl Roth; sunflower lecithin from Fichema s.r.o. Materials for finger replica preparation—FIMO^® soft oven-bake modelling clay and liquid silicon paste with a hardener were purchased from Staedtler.
Antimicrobial foam soap was purchased from Tork. Chlorhexidine digluconate (CHG) 25% w/w aqueous solution was provided by Zentiva, k.s. Two commercially available sanitisers used as a positive control for bacterial testing were purchased in a local store, i.e., ethanol-based gel (72% w/w) from Sanytol and 2% CHG alcoholic solution (IPA 70% v/v) from B. Braun Medical AG.