MALDI Open Access program
Users who run many samples may want to enroll in the MALDI Open Access program in which users run their own samples at a lesser cost than the standard service.
Open Access users need to attend a training session, which can take two hours.
When running samples, users need to bring:
- their own sample plate
- pipet tips and other supplies
- reagents beyond the calibration standards and matrices provided (cyanohydroxycinnamic acid, sinapinic acid, dihydroxybenzoic acid)
Use iLab to reserve the instrument and enter a service request. A surcharge is applied if users do not follow protocols.
Basic instructions are available in MS Word and pdf formats.
Matrices supplied:
Sinapinic (sinapic, ) 15 mg/ml in 50% acetonitrile, 0.1% trifluoroacetic acid
cyanohydroxycinnamic acid: 8 mg/ml in 80% methanol, 0.1% trifluoroacetic acid
dihydroxybenzoic acid; 10 mg/ml in 33% acetonitrile, 0.1% trifluoracetic acid
Calibrants
protein calibration standard I
| Protein | Charge state | Average mass |
|---|---|---|
| myoglobin | [M+H]+ | 16952.3 |
| cytochrome c | [M+H]+ | 12360.97 |
| ubiquitin I | [M+H]+ | 8565.76 |
| myoglobin | [M+2H]2+ | 8476.65 |
| cytochome c | [M+2H]2+ | 6180.99 |
| insulin | [M+H]+ | 5734.51 |
protein calibration standard II
| Protein | Charge state | Average mass |
|---|---|---|
| bovine albumin | [M+H]+ | approx 66.5 KDa |
| protein A | [M+H]+ | 44613 |
| bovine albumin | [M+2H]2+ | approx 33.3 KDa |
| trypsinogen | [M+H]+ | 23982 |
| protein A | [M+2H]2+ | 22307 |
Bovine albumin is not recommended for calibration because of heterogeneity and adduct formation .
peptide calibration standard
Masses are monoisotopic masses of singly charged peptide
| peptide | |
| somatostatin | 3147.4710 |
| ACTH clip 18-39 | 2465.1983 |
| ACTH clip 1-17 | 2093.0862 |
| renin substrate | 1758.9326 |