SmartSpin™
Light-coupled NMR on Spinsolve. A laser pulse on the sample, then a hyperpolarised spectrum in one scan.
Quotes and orders are handled by Magritek.
Photo-CIDNP in short
Photochemically induced dynamic nuclear polarisation. The sample stays in aqueous buffer at room temperature. The only trigger is light.
- 1
Light excites the dye
A laser pulse brings the photosensitiser to an excited triplet state.
- 2
A radical pair forms
The excited dye takes an electron from the molecule. The two become a pair of radicals with correlated electron spins.
- 3
Nuclear spins sort the pair
How fast the pair recombines depends on the nuclear spin state of the molecule, through the hyperfine coupling.
- 4
The molecule comes back polarised
After recombination its nuclear spin populations are far from thermal equilibrium. The NMR signal of those nuclei is enhanced.
What polarises
Not every molecule does. The enhancement depends on the molecule, the dye, the nucleus and the magnetic field.
- Tryptophan, tyrosine, histidine
- Indoles and phenols
- Many heteroaromatic scaffolds
- Fluorescein
- Flavin mononucleotide (FMN)
- Atto Thio 12
The setup
| Spectrometer | Spinsolve (60 MHz - 100 MHz) |
| Light source | LASER: 520 nm |
| Light path to the sample | Optically coupled, automation compatible |
| Sample | Standard NMR tubes 5mm |
| Automation | Autosampler 24 and 80 slots |
| Software | Spinsolve, Drug Design module |
Reference conditions
The fluorescein protocol used for the database measurements on Spinsolve 60-100 MHz.
| Photosensitiser | fluorescein, 20 µM |
| Compound | 200-500 µM |
| Buffer | 50 mM potassium phosphate, 100 mM KCl, pH 7.2 |
| Temperature | 298 K |
| Sample | 5 mm tube, 300-500 µL |
| Oxygen removal | GO-CAT (glucose oxidase, catalase) |
| Illumination | 520 nm, 1 W, 2 s |
| Acquisition | 1-16 scan |