Center for Plant Molecular Biology

Analytics

Sample Information - Metabolites

The customers are strongly advised to get in touch with the Analytics group prior to planning their experiments, harvesting and storing their samples. Statistical issues, necessary controls, amount of plant material per sample, fresh or freeze-dried storage conditions and background contamination due to unsuitable plastic ware are points, which have to be considered in advance.


Samples: „fresh weight material“

The amount of plant material needed is correlated to the type of analysis in question and should be discussed in advance. It depends on the different analytical platforms and their detection limits. Sample weights should not differ more than ± 5% and should be determined exactly for normalization.

The water status of the experimental plant material must be controlled for fresh weight analysis. Infiltrated leaf material or plants from liquid culture have to be padded dry carefully. Otherwise the „metabolite / weight“ ratio will be too variable for statistical calculations.

To reduce component degradation, samples should be homogenized shortly before the extraction procedure. In most cases this will be done by members of the Analytics lab using a ball mill. The detailed procedure has to be clarified depending on the analytical question.

The use of the following sample tubes is requested:

Screw cap micro tubes 2ml, PP (Sarstedt # 72.694.006)

Depending on the amount of samples , tubes can be obtained in advance from the Analytics group. Please label the sample tubes with consecutive numbers (e.g. 1,2,3,4,5…) and make sure, that the labeling is waterproof and resistent to cold storage conditions. Provide an excel file with the sample list containing:

- sample number
- sample information (treatment, genotype or…)
- sample weight
- sowing and harvest time points


Samples: „freeze-dried material“

If samples can be subjected to lyophilisation should be discussed in advance, as some metabolites are quite volatile and vanish during the process.

To reduce the amount of plasticizers and to avoid unwanted evaporation of organic solvents, the use of the following sample tubes is requested:

Safe Seal micro tube 2 ml , PP (Sarstedt)
Safe-Lock Tubes 2ml (Eppendorf)
Screw cap micro tubes 2ml, PP (Sarstedt)

Sample weights should not differ more than ± 5%. Labeling of the reaction tubes is in accordance to the fresh weight material samples (see above) .