What is the pH of TFA?
≈2
Trifluoroacetic acid (TFA) also generates a mobile phase pH of ≈2 at 0.1% v/v (Table 2), and for many years was the additive of choice for LC-MS at low pH. TFA also acts as an ion-pairing reagent, and is widely used for protein and peptide separations.
What is the pH of 0.05% TFA in water?
2.0 – 2.2
Specifications
| Property | Value |
|---|---|
| Particles > 2 µm | Max. 10 P/ml |
| pH (20 °C) | 2.0 – 2.2 |
| Calcium (Ca) | Max. 0.2 ppm |
| Potassium (K) | Max. 0.2 ppm |
What does TFA do in HPLC?
TFA is widely used as a mobile phase additive in the HPLC separation of biological molecules, such as proteins and peptides, because it acts as an ion-pairing reagent and equilibrates quickly so that it can be used with gradient elution.
Is TFA a buffer?
Ionic mobile phase additives like TFA serve one or more of the following functions: pH control (buffering), complexation with oppositely charged ionic groups to enhance RP retention (ion pairing), or suppression of adverse ionic interactions between peptides and silanol groups on the silica. At 0.1% TFA, they co-elute.
What is pH of 0.1% TFA?
pH 2.1
Most of you will also be aware that at pH 2.1 (approximately the pH of 0.1% v/v TFA), most basic analytes will be fully protonated (charged) and most acidic analytes will be fully protonated (uncharged).
Is TFA soluble in water?
Trifluoroacetic acid and water form an azeotrope, bp 105.5 °C, 20.8% water. Solubility: miscible with water and most organic solvents, but has limited solubility in alkanes (with more than six carbons) and carbon disulfide. Form Supplied in: neat liquid; commercially available.
How do you make 0.1 formic acid?
HPLC Mobile Phase:
- Formic acid in water (0.1%) Add 1 mL of 88 – 100 % formic acid to a 1000 mL graduated cylinder using a volumetric pipette or suitable electronic pipette.
- Formic acid in acetonitrile (0.1%)
What is the pH of 0.1% TFA?
How strong is TFA?
TFA is a stronger acid than acetic acid, having an acid ionisation constant, Ka, that is approximately 34,000 times higher, as the highly electronegative fluorine atoms and consequent electron-withdrawing nature of the trifluoromethyl group weakens the oxygen-hydrogen bond (allowing for greater acidity) and stabilises …
How do you make 0.1 formic acid in water?
What is TFA used for?
At a low concentration, TFA is used as an ion pairing agent in liquid chromatography (HPLC) of organic compounds, particularly peptides and small proteins. TFA is a versatile solvent for NMR spectroscopy (for materials stable in acid). It is also used as a calibrant in mass spectrometry.
Is TFA a weak acid?
What is the pH of a pKa of TFA?
The pKa of TFA is in the pH 0.2-0.5 region, depending on the reference you select. 0.1% TFA gives a pH of about 1.8-2.0. Regarding this, is trifluoroacetic acid a strong acid?
Is the pH of TFA 100% dissociated?
In the example above, TFA is a strong acid, so is 100% dissociated. In this case, the calculation is easy because the molarity for H+ ions is the same as the molarity of the acid. It is 0.026M. So, the pH is calculated for the example like this:
What is the density of a 1% TFA solution?
When we are making 1% stock solution of TFA, which is a very volatile acid, we prefer to weight the acid rather than use volumetric pipets. TFA density is 1.49. To make a 1 L of 1% TFA solution, we dissolved 10 g of TFA in water to the 1000 mL of solution.
What does 0.1% TFA mean in water?
The chromatography- and spectrometry-grade 0.1% TFA in water is 0.2-micron filtered, packaged in solvent-rinsed amber glass bottles and sealed under a nitrogen with PTFE-lined fluorocarbon caps for ultimate protection.