FAQ on Strontium Isotopic Ratios

1. Are the strontium concentrations provided along with the isotopic analysis?

We offer strontium concentrations as an additional service, in conjunction with the isotopic analysis. For pricing information, please contact us.

2. What is the pretreatment process for bone samples sent for strontium analysis?

The pretreatment for Sr analysis on bone consists of cleaning the surface of the sample by means of abrasion followed by rinsing with MQ water and sonication. After drying the sample, the most pristine part will be collected for sub-sampling. Sub-samples will be homogenized in pre-cleaned agate mortar and then sequentially reacted with 0.1 N acetic acid (8 rounds of treatment) to remove non-biogenic Sr (Hoppe et al, 2003).

3. Is plant material suitable for strontium analysis?

Yes, plant material can be submitted for this analysis. The sample must be dried prior to being sent in order for us to precisely measure the Sr isotopic ratio.

4. Can charred wood be submitted for strontium analysis? 

Yes we can accept charred wood. The samples should be clean and free of detritals. By conducting a visual inspection, the most clean part of the sample can be picked for submission.

5. How long can water samples be stored prior to being sent?

Water samples should be viable if stored at room temperature for up to six months.

6. What precision can you routinely achieve?

The precision on ⁸⁷Sr/⁸⁶Sr of NIST SRM 987 varies from ±0.000005 to ±0.000015 (%95 CI).

7. How many times is the Sr measurement done on each sample to produce a result?

The strontium value that we provide for each sample is an average of 5 measurements made sequentially. As for the number of measurements, we set up our method to do 10 measurements per block and we measure each sample in 5 blocks as mentioned. This means each sample will be measured 50 times.

8. Can XRF be used to determine Sr concentration?

Yes, but this will only give the Sr PPM total. If the concentration is too low, then mass spectrometry would need to be used for the measurements.

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Duration: 1 minute, 25 seconds || Speaker: Arash Sharifi, PhD
This video excerpt is part of Isobar Science’s webinar: Geochemistry and Application of Strontium Isotopes.
Disclaimer: This video is hosted in a third-party site and may contain advertising.