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Prepare the standard dilution series – Bio-Rad Human MMP and TIMP Assays User Manual

Page 15

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Prepare the Standard Dilution Series

The following procedure produces an eight-point standard curve with
a threefold dilution between each point. Pipet carefully using calibrated
pipets and use a new pipet tip for every volume transfer.

1. Label eight 1.5 ml microcentrifuge tubes S2 through S8 and Blank.

Alternatively, using Titertube

®

micro test tubes may prove to be more

convenient if a multichannel pipet will be used to load the plate.

2. Add 150 µl of the appropriate diluent to tubes S2–S8 and Blank.

(Figure 3).

3. Vortex reconstituted standards at medium speed for 5 sec before

removing any volume. Transfer 75 µl to the S2 tube containing the
chosen standard diluent. Vortex for 5 sec.

4. Use a new pipet tip to transfer 75 µl from the S2 tube to the S3 tube.

Vortex for 5 sec.

5. Continue with 1:3 (threefold) serial dilutions as shown in Figure 3.

6. Use reconstituted and diluted standards and controls immediately.

Do not freeze for future use.

Fig. 3. Preparing a threefold dilution series with a single reconstituted standard.

150 150 150 150 150 150 150 150

S1

S2 S3 S4 S5 S6 S7 S8

Blank

Diluent, µl

75

75 75 75 75 75 75

Transfer Volume, µl

Reconstituted

Standard