Dilution station

You'll prepare and measure a CK dilution, then calculate the patient result. The bench also has serial dilutions, titer racks and worksheet reviews.

What to know first: Dilution Math
Laboratory Mathematics and Diagnostic Performance
How long it takes: About 5 minutes for a single dilution and about 10 for a series.
What's free: The first CK order, a 1:5 dilution, opens without an account. A free account opens the first three cases. Full access opens the rest.

Dilute the first CK orderWorking at the bench needs JavaScript.

Dilution station

When CK is over the analyzer's 50 to 1000 U/L range, dilute it, rerun, and multiply the reading by the dilution factor. You'll need JavaScript to work through the case.

Parts: A 1:5 dilution is 1 part specimen + 4 parts diluent = 5 total parts
Specimen part: Final volume ÷ total parts
Patient result: Measured diluted result × total parts

One specimen part with four diluent parts makes a 1:5 dilution. One specimen part with five diluent parts makes six total parts. — One part specimen plus five parts diluent is six total parts, so the dilution factor is 6.

Read the dilution math lesson

Serial dilutions

A 100 mg/L solution has 100 mg in every liter. Diluent adds volume and no analyte. An aliquot is the measured portion you move.

In a twofold series, transfer an aliquot from each mixed tube into the next tube. The concentration halves at each step, from 100 to 50 to 25 to 12.5 mg/L. Total dilution factors are 2, 4 and 8. Removing an aliquot from a mixed tube does not change its concentration.

The serial dilution controls need JavaScript. Read serial dilution explanations.