Sample Retrieval for Multiple Viscosity Measurements: 20 Different Shear Rates with 18 µL of Sample!

In addition to the low sample volume consumption, VROC^® initium viscometer features sample retrieval, allowing to reuse a small quantity of sample for repeated tests. This functionality enables the characterization of samples over a wide range of shear rates with just about a tear drop! For this application brief, we tested a single 18 µL sample of Bovine Serum Albumin (BSA) 302 mg/mL in water at 20 different shear rates!

The test was conducted as follows:

1. 25 µL of BSA (302 mg/ml in water) was loaded into an 11 mm vial with a 300 µL small-volume insert (Wheaton)
2. The autosampler loaded 18 µL of the sample into the VROC^® initium viscometer
3. VROC^® initium performed multiple shear rate measurements on the sample, retrieving the sample when required
4. VROC^® initium performed self-cleaning at the end of the test with preset protocols

Overall, 18 µL of BSA was consumed to test at 20 different shear rates, from 1066 to 2840 1/s. The BSA sample exhibits Newtonian behavior across the range tested (See Figure), with an average viscosity of 6.078cP at 25 ^oC, and a relative standard deviation of 0.51%!

 Want to read more about automating your viscosity measurements? Visit our application library! ↓