Ostro Sample Preparation Products: Recovery

As part of the evaluation of the Ostro plate, recovery for a broad range of analytes in human and rat plasma was evaluated to judge how well potential target compounds could be quantified.

Benefits

The Ostro plate demonstrates excellent recovery across a variety of conditions

Recovery determination is important for quantitative methods in that it provides a measure of the actual amount of analyte obtained from the matrix using a particular sample preparation device or technique. As part of the evaluation of the Ostro plate, recovery for a broad range of analytes in human and rat plasma was evaluated to judge how well potential target com-pounds could be quantified.

Samples

• Human or rat plasma fortified at high, medium, and low concentrations
  • Low concentration range: 0.2-40 ng/mL
  • Medium concentration range: 2-400 ng/mL
  • High concentration range: 20-4,000 ng/mL
• 3 loading volumes:
  • 50 μL plasma: 150 μL of 1% HCOOH in ACN
  • 100 μL plasma: 300 μL of 1% HCOOH in ACN
  • 200 μL plasma: 600 μL of 1% HCOOH in ACN

Analyte mixture

Protocol

• Load plasma onto Ostro plate
  
• Load extraction solvent
• Aspirate 3X using electronic pipette set at same volume as extraction solvent
• Pull through using vacuum set at 15” Hg for 5 minutes
• Dry down using nitrogen gas
• Reconstitute in same volume as plasma (50 μL, 100 μL, or 200 μL)
• Inject 8 μL into 10 μL loop

* To improve recovery for small sample volumes, you may increase the ratio of organic solvent to plasma. Use of Waters Positive Pressure-96 Processor has also been shown to improve recovery.

The Ostro plate demonstrates excellent recovery across a variety of conditions. In this evaluation, low, medium, and high concentrations of a range of compounds were examined and were consistently recovered using the device. This robustness was shown in both rat and human plasma.