| Step | Instrument | Comment |
|---|---|---|
| 1 | Choose the matrix for your sample. 选择合适的基质 | |
| 2 | verify sample is completely dry. 确认样品是干燥的 | Poor vacuum (poor signal and resolution) as well as long transfer times will result from wet samples. 湿样品将导致真空失效（信号质量和解析度将下降） |
| 3 | Check status lights on the instrument panel | Mains: Green System: Ready or Warm-up Target: Access |
| 4 | Remove sample plate | Always store sample carrier in instrument to ensure that the next person can find it |
| 5 | Place plate on carrier | Sample “coin chip” is keyed to only fit one way. Ensure plate sits flush with the top of the carrier and sample plate is flat. Otherwise, sample may scratch sealing surface and cause a leak. |
| 6 | Load Plate into Loading Dock | |
| 7 | Eject | Press the Eject Button in the starting screen (or the large green button on the side of the MS-MALDI to insert your sample |
| 8 | Select Method | The naming convention is for basic operation “RP_(0.5k-4kDa).par” First character = TOF mode: L = linear / R = Reflectron Second Character = polarity: P = positive / N = Negative Third phrase = optimized and calibrated molecular weight range |
| 9 | Set Scan Parameters | |
| 10 | Select correct positions of the sample in the plate view | |
| 11 | Set Laser Parameters | Select an appropriate number of shots and frequency of shots for your sample. Also, set the laser offset to approximately 10-15%. |
| 12 | Press start | Move the crosshairs around the sample (left click with mouse) to find a good spot. You may also need to change the aforementioned settings. Note: if you are getting a “hump” near the left of the spectrum, you are likely using too much laser power. |
| 13 | Save Spectrum |
After obtaining a satisfactory spectrum, save it to the database. Run additional scans if necessary. |
| 14 | Finish |
Press the Eject Button in the starting screen (or the large green button on the side of the MALDI. Remove the sample and insert the plate back into MALDI. Press the Eject Button again and the plate should be inside MALDI. Properly dispose of the sample. |
| Compound | Alias | Solvent | Wavelength (nm) | Application | |
|---|---|---|---|---|---|
| 2,5-dihydroxy benzoic acid | DHB Gentisic acid | acetonitrile, water, methanol, acetone, chloroform | 337, 355, 266 | peptides, nucleotides, oligonucleotides, oligosaccharides | |
| 3,5-dimethoxy-4-hydroxycinnamic acid | sinapic acid; sinapinic acid; SA | acetonitrile, water, acetone, chloroform | 337, 355, 266 | peptides, proteins, lipids | |
| 4-hydroxy-3-methoxycinnamic acid | ferulic acid | acetonitrile, water,propanol | 337, 355, 266 | proteins | |
| α-Cyano-4-hydroxycinnamic acid | CHCA | acetonitrile, water,ethanol, acetone | 337, 355 | peptides, lipids, nucleotides | |
| Picolinic acid | PA | Ethanol | 266 | oligonucleotides | |
| 3-hydroxy picolinic acid | HPA | Ethanol | 337, 355 | oligonucleotides | |
| Method Name | IS1 | IS2 | Lens | Refl. | Refl 2 | Delay |
| RP_(0-1kDa) | 19 | 16.72 | 8.3 | 21 | 9.7 | 0 |
| RP_(0.5k-4kDa) | 19 | 16.53 | 8.49 | 21 | 9.7 | 0 |
| RP_(3k-6kDa) | 19 | 16.72 | 8.55 | 21 | 9.7 | 150 |
| LP_(0.5k-4kDa) | 20 | 18.6 | 7 | N/A | N/A | 0 |
| LP_(2k-20kDa) | 20 | 18.5 | 8.5 | N/A | N/A | 150 |
| LP_(10k-150kDa) | 20 | 17.85 | 9 | N/A | N/A | 300 |
| LP_(30k-300kDa) | 20 | 17.86 | 9 | N/A | N/A | 500 |
| RN_(0-1kDa) | 19 | 16.75 | 7.5 | 21 | 9.7 | 0 |
| RN_(0.5k-4kDa) | 19 | 16.76 | 8.3 | 21 | 9.7 | 0 |
| RN_(2k-10kDa) | 19 | 17.1 | 8.55 | 21 | 8.4 | 250 |
| LN_(0.5k-20kDa) | 20 | 18.1 | 8.5 | N/A | N/A | 150 |