TiO2 protocol

Titanium Oxide Method for Phosphopeptde enrichment using Lactic acid.

Sugiyama et al. Proteomics.2007; 6: 1103-1109

1. Carry out digestion as one would do otherwise. Use either trypsin or Lys-C

2. Prepare Solution A – 0.1% TFA, 80% acetonitrile, 300mg/ml of Lactic acid, Solution B – 0.1%TFA, 80% acetonitrile

3. Prepate the titania cartridge by putting 10ul of total TiO2 ( 1.2ml 50% acetonitrile per tube of TiO2) and additional 10ul of 50% ACN, OR use the ready made TopTip

4. Dissolve the digest in either 20ul or 100ul of Sol A

5. Equilibrate the titania column with Sol A

6. Load the sample

7. Wash with Sol A and then Sol. B

8. Elute with 0.5% NH4OH

9. Neutralize with equal amount of 1% TFA

10. Dry the sample and analyse with MS