Domiphen bromide

All bacterial toxins were purchased from List Biological Laboratories (Campbell, CA, USA). An FDA-approved drug library comprising of 1,585 drugs was purchased from Johns Hopkins University Bloomberg School of Public Health, titled, Johns Hopkins Clinical Compound Library (JHCCL). The drugs in the library were kept at −20 °C as 3.3 mM stock solutions in sealed microtiter plates and were made using DMSO as solvent. Compounds of interest were repurchased and reproduced from 3.3 mM solutions. Salmon sperm protamine, cetylpyridinium bromide, domiphen bromide, cetalkonium chloride, sodium lauryl sulfate, ascorbic acid 6-palmitate, sodium dodecylbenzenesulfonate, docusate sodium, and candesartan cilexetil were purchased from Sigma-Aldrich (St. Louis, MO, USA). Thyropropic acid was purchased from Toronto Research Chemicals Inc (Toronto, Ontario, Canada). All drugs were prepared at 3.3 mM using DMSO as a solvent. Full-length human and truncated salmon and human protamines were synthesized by LifeTein (Hillsborough, NJ, USA). All chemicals and peptides in this study had purities greater than 98%.

QACs: benzalkonium chloride (BC), benzethonium chloride (BZ), cetylpyridinium chloride (CP), cetyltrimethylpyridinium chloride (CTAB), and domiphen bromide (DB) were purchased from Sigma-Aldrich (Steinheim, Germany).
The ILs used in this study were either (a) provided by Proionic GmbH (Grambach, Austria) with a nominal purity of >98%, (b) purchased from Iolitec (Ionic Liquid Technologies GmbH, Heilbronn, Germany) with a nominal purity of >98%, or (c) synthesized in our laboratory, according to the CBILS© route (CBILS is a registered trademark of Proionic GmbH; Kalb et al., 2005 , 2016 (link)). The following ILs were investigated as: ILs with one elongated alkyl side chain 1-decyl-3-methylimidazolium chloride ([C₁₀mim][Cl];a), 1-dodecyl-3-methylimidazolium chloride ([C₁₂mim][Cl];b), 1-methyl-3-tetradecylimidazolium chloride ([C₁₄mim][Cl];b), 1-hexadecyl-3-methylimidazolium chloride ([C₁₆mim][Cl];b) trimethyldecylammonium chloride ([TMC₁₀A][Cl];c), trimethylhexadecylammonium chloride ([TMC₁₆A][Cl];c). ILs with two elongated alkyl side chains dioctyldimethylammonium chloride ([DC₈DMA][Cl];c) and 1-3-didecyl-2-imidazolium chloride ([C₁₀C₁₀im][Cl];b). ILs with three elongated alkyl side chains trioctylmethylammonium chloride ([TC₈MA][Cl];a) and trioctylmethylphosphonium chloride ([TMC₁₀P][Cl];c).