| Substance | pKa | dpKa/dT | Mr |
|---|---|---|---|
| Oxalate (oxalic acid) (pK1) | 1.27 | 90.0 | |
| Maleate (maleic acid) (pK1) | 2.00 | 0 | 116.1 |
| Phosphate (phosphoric acid) (pK1) | 2.15 | 0.0044 | 98.0 |
| Glycine (pK1) | 2.35 | −0.002 | 75.1 |
| Phthalate (phthalic acid) (pK1) | 2.95 | 0.0020 | 166.1 |
| Glycylglycine (pK1) | 3.12 | 132.1 | |
| Malate (malic acid) (pK1) | 3.40 | 134.1 | |
| Formiate (formic acid) | 3.75 | 0 | 46.0 |
| Barbituric acid (pK1) | 4.04 | 128.1 | |
| Succinate (succinic acid) (pK1) | 4.21 | −0.0018 | 118.1 |
| Oxalate (oxalic acid) (pK2) | 4.27 | 90.0 | |
| Acetate (acetic acid) | 4.75 | 0.0002 | 60.0 |
| Citrate (citric acid) (pK2) | 4.76 | −0.0016 | 192.1 |
| Malate (malic acid) (pK2) | 5.13 | 134.1 | |
| Pyridine | 5.23 | −0.014 | 79.1 |
| Phthalate (phthalic acid) (pK2) | 5.41 | 166.1 | |
| Piperazine (pK2) | 5.55 | −0.015 | 86.1 |
| Succinate (succinic acid) (pK2) | 5.64 | 0 | 118.1 |
| Malonate (malonic acid) (pK2) | 5.70 | 104.1 | |
| Histidine (pK2) | 5.97 | −0.017 | 155.2 |
| Maleate (maleic acid) (pK2) | 6.07 | 116.1 | |
| MES (2-morpholinoethanesulfonic acid) | 6.10 | −0.011 | 195.2 |
| Cacodylate (cacodylic acid. dimethy-larsinic acid) | 6.27 | 138.0 | |
| Carbonate (carbonic acid) (pK1) | 6.35 | −0.0055 | 62.0 |
| Citrate (citric acid) (pK3) | 6.40 | 0 | 192.1 |
| BIS-Tris (bis(2-hydroxyethyl) imino-tris(hydroxymethyl)-methane) | 6.46 | −0.02 | 209.5 |
| ADA (N-carbamoylmethyl-iminodiacetic acid) | 6.59 | −0.011 | 190.2 |
| PIPES (1.4-piperazine-bis-ethane sulfonic acid) | 6.76 | −0.0085 | 302.4 |
| ACES (N-(2-acetamido)-2- aminoethanesulfonic acid) | 6.78 | −0.02 | 182.2 |
| BIS-Tris Propane (1.3-bis[tris(hydroxy- methyl)- methylamino]-propane) (pK1) | 6.80 | −0.028 | 282.3 |
| Imidazole | 6.95 | −0.02 | 68.1 |
| MOPSO (3-(N-morpholino)-2-hydroxypopanesulfonic acid) | 6.95 | −0.015 | 225.3 |
| BES (2-[bis(2-hydroxyethyl)-amino]- ethansulfonsäure) | 7.09 | −0.016 | 213.3 |
| Phosphate (phosphoric acid) (pK2) | 7.21 | −0.0028 | 98 |
| MOPS (4-morpholino-propane sulfonic | 7.31 | −0.011 | 209.3 |
| TES (2-[tris(hydroxymethyl)-methyl-amino]-1-ethanesulfonic acid) | 7.40 | −0.02 | 229.5 |
| HEPES (4-(2-hydroxyethyl)-1-piperazine-ethanesulfonic acid) | 7.48 | −0.014 | 238.3 |
| DIPSO (3-[bis(2-hydroxyethyl)amino]-2- hydroxypropane-1-sulfonic acid) | 7.60 | −0.02 | 243.3 |
| Triethanolamine (TEA) | 7.76 | −0.02 | 149.2 |
| POPSO (piperazine-N.Nt-bis(2-hydroxypropanesulfonic acid)) | 7.85 | −0.013 | 362.4 |
| Barbital (diethylbarbituric acid, Veronal) | 7.98 | 184.2 | |
| HEPPS (EPPS. 4-(2-hydroxyethyl)-1-piperazin-propanesulfonic acid) | 8.00 | 252.3 | |
| Tricine (N-[tris(hydroxymethyl)-methyl]-glycine) | 8.05 | −0.021 | 179.2 |
| Glycinamide hydrochloride | 8.06 | −0.029 | 110.5 |
| Tris (tris(hydroxymethyl)-amino methan; 2-amino-2-hydroxy methyl-propane-1.3-diol; Trizma) | 8.06 | −0.028 | 121.1 |
| PIPPS (1.4-bis(3-sulfopropyl)-piperazine) | 8.10 | 330.4 | |
| Glycylglycine (pK2) | 8.25 | −0.025 | 132.1 |
| Bicine (N.N-bis(2-hydroxyethyl)-glycine) | 8.26 | −0.018 | 163.2 |
| TAPS (3-tris(hydroxymethyl)-methylamino)-1-propanesulfonic acid | 8.40 | 0.018 | 243.3 |
| AMPSO (3-([1.1-dimethyl- 2-hydoxyethyl]amino)-2-hydroxypropane sulfonic acid) | 8.40 | 227.3 | |
| Diethanolamine | 8.88 | 105.1 | |
| Histidine (pK3) | 8.97 | 155.2 | |
| BIS-Tris propane (1.3-bis[tris (hydroxymethyl)-methylamino] propane) (pK2) | 9.00 | −0.028 | 282.3 |
| AES (2-aminoethylsulfonic acid; taurine) | 9.06 | −0.022 | 125.2 |
| Borate (boric acid. H3BO3) | 9.23 | −0.008 | 61.8 |
| Ammonia | 9.25 | −0.031 | 17 |
| Ethanolamine | 9.50 | −0.029 | 61.1 |
| CHES (2-cyclohexylaminoethanesulfonic acid) | 9.55 | −0.018 | 207.3 |
| CAPSO (3-cyclohexylamino-2- hydroxypropanesulfonic acid) | 9.71 | −0.018 | 237.3 |
| Glycine (pK2) | 9.78 | −0.025 | 75.1 |
| EDPS (N.Nt-bis(3-sulfopropyl)-ethylenediamine) | 9.80 | ||
| Carbonate (carbonic acid) (pK2) | 10.33 | −0.009 | 62 |
| CAPS (3-(cyclohexylamino)-1-propanesulfonic acid) | 10.40 | 0.032 | 221.3 |
| Ethylamine | 10.62 | 45.1 | |
| Triethylamine | 10.72 | 101.2 | |
| Piperidine | 11.12 | −0.031 | 85.2 |
| Phosphate (phosphoric acid) (pK3) | 12.33 | −0.026 | 98.0 |
Souce: NovoPro 2019-07-02