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. 2019 Oct 1;1(11):4207–4237. doi: 10.1039/c9na00308h

Examples of hydrophobic ion pairing, sorted by therapeutic.

Name Structure/etc. Paired with Formulation technique
α-Chymotrypsin 25 kDa protein, 241 residues, pI: 8.75 Sodium docusate167 Solvent evaporation with polymethyl methacrylate, polystyrene, or poly(vinyl acetate)167
α-Lipoic acid graphic file with name c9na00308h-u51.jpg N,N′-Dibenzylethylene diamine (DBDA),47 note: included pamoic acid to frustrate αLA : DBDA recrystallization and improve encapsulation PLA-b-PEG NPs by Flash NanoPrecipitation, in situ HIP47
Am80 graphic file with name c9na00308h-u52.jpg N,N-Dimethyldodecyl amine (DDA)40 Block copolymer micelles by evaporation-sonication40
N,N-Dimethylhexyl amine40
N,N-Dimethyloctadecyl amine40
Atazanavir graphic file with name c9na00308h-u53.jpg 2-Naphthalene sulfonic acid28 SEDDS28
Sodium docusate (AOT)28
Atenolol graphic file with name c9na00308h-u54.jpg Brilliant blue FCF155 PLGA NPs by nanoprecipitation155
AZD2811 graphic file with name c9na00308h-u55.jpg Oleic acid38,89 Oil in water (o/w) nanoemulsification solvent extraction to form PLA-PEG NPs using in situ HIP38,89
1-Hydroxy-2-naphthoic acid38,89
Cholic acid38,89
Sodium deoxycholate38
Docusate sodium38,89
Pamoic acid38
Berberine graphic file with name c9na00308h-u56.jpg Oleic acid161 Liquid crystalline nanoparticulates by a hydrotrope method161
Bevacizumab 149 kDa antibody Docusate sodium168 Lipid coacervation168
Bovine serum albumin (BSA) 66.5 kDa protein, 583 residues, pI: 4.7 Cholic acid56 Double emulsion56
CM-PEG56 Single emulsion56
Sodium dodecyl sulfate56
Taurocholic acid56
Sodium docusate56 Double emulsion56
Single emulsion56
SEDDS169
Dextran sulfate91 Solid in oil in water (S/O/W) to form PLGA NPs91
Sodium deoxycholate165 SEDDS165
Sodium laurate165
Sodium stearoyl glutamate165
Pamoic acid disodium165
Bromothymol blue graphic file with name c9na00308h-u57.jpg Tetrabutylammonium bromide66 Encapsulated into polystyrene microparticles using compressed carbon dioxide66
Tetrahexylammonium bromide66
Tetraoctylammonium bromide66
Chlorhexidine graphic file with name c9na00308h-u58.jpg Losartan152 Nanoprecipitation152
Cinnarizine graphic file with name c9na00308h-u59.jpg Pamoic acid,47 note: Also unsuccessfully tried camphor-10 sulfonic acid (micellized), cinnamic acid, palmitic acid, and oleic acid PLA-b-PEG NPs by Flash NanoPrecipitation, in situ HIP47
Ciprofloxacin graphic file with name c9na00308h-u60.jpg Sodium deoxycholate88 Oil-in-water (o/w) submicron emulsion88
Cisplatin graphic file with name c9na00308h-u61.jpg Sodium docusate83 Stearic acid coacervation83
Clozapine graphic file with name c9na00308h-u62.jpg Pamoic acid47 PLA-b-PEG NPs by Flash NanoPrecipitation, in situ HIP47
Colistin graphic file with name c9na00308h-u63.jpg Cholesteryl hemisuccinate156 PLA NPs by emulsion evaporation156
N,N-Dipalmitoyl-l-lysine156
Sodium cholesteryl sulfate156
Concanavalin A 104–112 kDa protein (tetramer), pI: 4.5–5.5 Sodium docusate167 Solvent evaporation with polymethyl methacrylate, polystyrene, or poly(vinyl acetate)167
Dalargin graphic file with name c9na00308h-u64.jpg Dextran sulfate104 PLGA-PEG NPs by S/O/W emulsion104
Daptomycin graphic file with name c9na00308h-u65.jpg Arginine-hexadecanoyl ester41 N/A; proof-of-concept HIP using novel cationic surfactants demonstrates precipitation and increased log P41
Arginine-nonyl ester41
Desmopressin graphic file with name c9na00308h-u66.jpg Oleic acid77 SEDDS45,77,86,170
Sodium docusate45,77,86,170
Sodium dodecyl sulfate77,86
Sodium stearate77 (note: less effective than SDS, AOT, and oleate)
Sodium stearyl sulfate77 (note: less effective than SDS, AOT, and oleate)
Dexamethasone valine valine prodrug graphic file with name c9na00308h-u67.jpg Dextran sulfate120 PLGA NPs by S/O/W emulsion120
Donepezil graphic file with name c9na00308h-u68.jpg Pamoic acid166 High pressure homogenization with d-α-tocopherol polyethylene glycol 1000 succinate166
Dorzolamide graphic file with name c9na00308h-u69.jpg Oleic acid81 PLGA NPs or PEG3-PSA microparticles by S/O/W emulsion81
Sodium dodecyl sulfate81
Doxorubicin graphic file with name c9na00308h-u70.jpg Alginic acid61 Microemulsion by stearic acid coacervation61
Cholesteryl hemisuccinate112 Thin film dispersion112
Dextran sulfate61,95 Microemulsion by stearic acid coacervation61
Warm wax microemulsion solvent evaporation95
Dioleoyl phosphatidic acid (DOPA)71 PLA-b-PEG NPs by nanoprecipitation71
Docosahexaenoic acid70 SLNs by hot melt ultrasound emulsification70
Hexadecylphosphate158 SLNs by warm oil-in-water microemulsion with stearic acid and taurocholate sodium158
Hyaluronic acid153 Thin film dispersion by lipid film hydration with suspended HIP complex and homogenization153
Oleic acid106,121 70 °C high-pressure homogenization121
High-pressure film homogenization106
Sodium acetate61 Microemulsion by stearic acid coacervation61
Sodium alginate61 Microemulsion by stearic acid coacervation61
Sodium decanesulfonate116 Microemulsion by stearic acid coacervation116
Sodium docusate116 Microemulsion by stearic acid coacervation116
Sodium stearate61 Microemulsion by stearic acid coacervation61
Sodium taurodeoxycholate72,95,116 Warm wax microemulsion solvent evaporation95
Microemulsion by stearic acid coacervation116
Microemulsion by shear and ultrasonic homogenization after drying from molten stearyl alcohol72
Sodium tetradecyl sulfate95 Warm wax microemulsion solvent evaporation95
Vitamin E succinate105 SLNs by hot melt ultrasound emulsification105
Gefitinib graphic file with name c9na00308h-u71.jpg Dioleoyl phosphatidic acid (DOPA)30 Nanoprecipitation with doxorubicin-conjugated PLA-b-PEG NPs30
Gentamicin graphic file with name c9na00308h-u72.jpg Sodium docusate82,117–119,171 PLA microparticles by precipitation with compressed antisolvent117,171
Microparticles by PCA using stabilizer poly(methyl vinyl ether-co-maleic anhydride)118
PCA with no stabilizer82,119
PLGA NPs by emulsion solvent evaporation82,119
Heparin graphic file with name c9na00308h-u73.jpg Arginine-hexadecanoyl ester41 N/A; proof-of-concept HIP using novel cationic surfactants demonstrates precipitation and increased log P41
Arginine-nonyl ester41
Idarubicin graphic file with name c9na00308h-u74.jpg Dextran sulfate95 Warm wax microemulsion solvent evaporation95
Sodium taurodeoxycholate95
Sodium tetradecyl sulfate95
IGG-Fab fragment 48 kDa protein Sodium dodecyl sulfate90 Modified nanoprecipitation90
Taurocholic acid90 S/O/W PLGA NPs90
Dextran sulfate90
Insulin 5.8 kDa peptide, 51 residues (6 cationic and 6 anionic), pI: 5.3 Cholic acid157 Reverse micelle-double emulsion using palmitic and stearic acid157
Chitosan53 Homogenization and stabilization with SDS53
Dimyristoyl phosphatidyl glycerol42 SNEDDS42
Oleic acid58,102,162 S/O/W emulsion58
PLGA NPs by emulsion solvent diffusion102,162
Pamoic acid disodium165 SEDDS165
Sodium laurate165
Sodium stearoyl glutamate165
Sodium deoxycholate80,93,165 PLGA NPs by emulsion solvent diffusion93
S/O/W emulsion80
SEDDS165
Sodium docusate84,86 SEDDS86
Stearic acid coacervation84
Sodium dodecyl sulfate49,84,111,177,178 Stearic acid coacervation84
PLGA NPs by emulsion solvent diffusion111,177,178
Electrospray with stearic or pamoic acid49
Irinotecan graphic file with name c9na00308h-u75.jpg Sodium docusate29 PEG-b-PLGA NPs via water/oil/water double emulsion; in situ HIP29
Sodium dodecyl sulfate29
Sodium tripolyphosphate29
Isoniazid methanesulfonate graphic file with name c9na00308h-u76.jpg Tetraheptylammonium bromide179 Precipitation with compressed antisolvent (PCA)179
Tetrapentylammonium bromide179
Lanreotide graphic file with name c9na00308h-u77.jpg Sodium deoxycholate98 SNEDS98
Sodium docusate98
Sodium stearyl sulfate98
Taurocholic acid98
Leuprolide graphic file with name c9na00308h-u78.jpg Oleic acid94,101 PLGA microspheres by O/W emulsion101
SMEDDS94
Sodium deoxycholate165 SEDDS165
Sodium laurate165
Sodium stearoyl glutamate165
Pamoic acid disodium165
Sodium docusate45,84,86,172 SEDDS45,86
Stearic acid coacervation84
Oligosaccharide ester microparticles by spray drying172
Solid lipid nanoparticles and nanostructured lipid carriers by high pressure homogenization110
Sodium dodecyl sulfate11,84 Stearic acid coacervation84
Hydrogen bonding complexation between polyacrylic acid and Pluronic F68 (ref. 11)
Sodium stearate87 Solid lipid NPs by: solvent diffusion87
Oil-in-oil (O/O) emulsion-evaporation87
Loperamide graphic file with name c9na00308h-u79.jpg Dextran sulfate104 PLGA-PEG NPs by S/O/W emulsion104
Losartan graphic file with name c9na00308h-u80.jpg Chlorhexidine152 Nanoprecipitation152
Lumefantrine graphic file with name c9na00308h-u81.jpg Oleic acid48 SEDDS48
Lycobetaine graphic file with name c9na00308h-u82.jpg Oleic acid163 Emulsion by lipid film hydration high-pressure homogenization163
Lysozyme 14.4 kDa protein, 129 residues, pI: 11.35 Cholic acid56 Double emulsion56
Single emulsion56
CM-PEG56 Double emulsion56
Single emulsion56
Dextran sulfate59 Emulsion solvent diffusion59
Oleic acid57,58 PLGA NPs by emulsion diffusion57
S/O/W emulsion58
Sodium docusate56 Double emulsion56
Single emulsion56
Sodium dodecyl sulfate18,57 PLGA NPs by emulsion diffusion57
S/O/W emulsion: Polymer/lipid NPs18
Taurocholic acid56 Double emulsion56
Single emulsion56
Melittin 2.8 kDa peptide, 26 residues, pI: 12.01 Sodium dodecyl sulfate109 PLGA nanoparticles by emulsion solvent diffusion109
Minocycline graphic file with name c9na00308h-u83.jpg Sodium docusate173 PLGA NPs by emulsion-solvent-diffusion173
Mitoxantrone dihydrochloride graphic file with name c9na00308h-u84.jpg Sodium deoxycholate79 Nanoprecipitation79
Mtb8.4 Protein, TB antigen, pI: 6.3 Sodium docusate174 PLG microspheres by emulsification174
Naloxone graphic file with name c9na00308h-u85.jpg Sodium docusate117 PLA microparticles by precipitation with compressed antisolvent117
Naltrexone graphic file with name c9na00308h-u86.jpg Sodium docusate117 PLA microparticles by precipitation with compressed antisolvent117
Octreotide graphic file with name c9na00308h-u87.jpg Dextran sulfate92 S/O/W emulsion92
Oleic acid96 SNEDDS96
Sodium decanoate9,96 SNEDDS96
SEDDS9
Sodium deoxycholate9,96 SNEDDS96
SEDDS9
Sodium docusate9 SEDDS9
Sodium dodecyl sulfate92,96 S/O/W emulsion92
SNEDDS96
Ovalbumin (OVA) 43 kDa protein, 385 residues, pI: 5.19 Cetrimonium bromide (CTAB)39 pH-sensitive polyketal microparticles by single emulsion39
OZ439 mesylate (artefenomel) graphic file with name c9na00308h-u88.jpg Sodium oleate43,154 HPMCAS NPs by Flash NanoPrecipitation; in situ HIP43,154
Papain 23.4 kDa protein, 212 residues, pI: 8.8–9.6 Sodium deoxycholate97 SEDDS97
Pemetrexed graphic file with name c9na00308h-u89.jpg Cetrimonium bromide (CTAB)103 Lyotropic liquid crystalline nanoparticles by homogenization (in situ HIP)103
N α-Deoxycholyl-l-lysyl-methylester4 W/O/W emulsion4
Polymyxin B graphic file with name c9na00308h-u90.jpg Oleic acid sodium salt78 PCL-b-PEG NPs by Flash NanoPrecipitation (FNP), in situ HIP,78 note: sodium decanoate, myristate, deoxycholate, 2-naphthalenesulfonate, 1-heptanesulfonate, 1-octane-sulfonate, and 1-decanesulfonate formed a precipitate when mixed with polymyxin B at 1 : 1 charge ratio but did not form NPs by FNP. Sodium hexanoate, benzenesulfonic acid, camphorsulfonic acid, and 1,2-ethanesulfonate did not form a precipitate when mixed with polymyxin B at 1 : 1 charge ratio.
Pamoic acid sodium salt78
Sodium dodecyl sulfate78
Sodium dodecyl benzenesulfonate78
Poly(inosinic acid)-poly (cytidylic acid) (poly(I : C)) Double-stranded RNA analog, TLR3 agonist Cetrimonium bromide (CTAB)39 pH-sensitive polyketal microparticles by single emulsion39
Propranolol graphic file with name c9na00308h-u91.jpg Alginic acid61 Microemulsion by stearic acid coacervation61
Dextran sulfate61
Sodium acetate61
Sodium stearate61
Quinidine sulfate graphic file with name c9na00308h-u92.jpg Alginic acid61 Microemulsion by stearic acid coacervation61
Dextran sulfate61
Sodium acetate61
Sodium stearate61
r-met-HuGdNF Recombinant methionyl human Glial-cell line derived neurotrophic factor Cholic acid56 Double emulsion56, single emulsion56
CM-PEG56
Sodium docusate56
Sodium dodecyl sulfate56
Taurocholic acid56
Retinoic acid graphic file with name c9na00308h-u93.jpg Benethamine65,108,115 Hot melt homogenization using ultrasound emulsification41–43,65,108,115
Laurylamine46,107,114
Maprotiline (both HCl and free base)115
Stearylamine46,65,107,114
Triethylamine46,65,107,114
Rose bengal graphic file with name c9na00308h-u94.jpg Tetrabutylammonium bromide66 Encapsulated into polystyrene microparticles using compressed carbon dioxide to plasticize polystyrene MPs and allow diffusion in66
Tetrahexylammonium bromide66
Tetraoctylammonium bromide66
Salmon calcitonin 3.4 kDa peptide, 32 residues, pI: 8.86 Dimyristoyl phosphatidyl glycerol (DMPG)85 PLGA NPs by solvent diffusion85
Oleic acid85
Sodium deoxycholate85
Thymopentin graphic file with name c9na00308h-u95.jpg Hexadecylphosphate159 Warm oil in water microemulsion159
Tobramycin graphic file with name c9na00308h-u96.jpg Hexadecylphosphate160 Warm oil in water microemulsion160
Sodium docusate175 PLGA NPs by O/W emulsion175
Trypsin 23 kDa protein, 220 residues, pI: 10.1–10.5 Sodium docusate167 Solvent evaporation with polymethyl methacrylate, polystyrene, or poly(vinyl acetate)167
Vancomycin graphic file with name c9na00308h-u97.jpg Linoleic acid64 Hot homogenization and ultrasonication64
Sodium docusate176 SEDDS176
Verapamil graphic file with name c9na00308h-u98.jpg Alginic acid61 Microemulsion by stearic acid coacervation61
Dextran sulfate61
Sodium acetate61
Sodium stearate61
Vincristine graphic file with name c9na00308h-u99.jpg Oleic acid164 High pressure homogenization164