Simple ProcedureDPPH and Trolox are unstable in solution. Please prepare immediately before using.DPPH content needs to be checked by measuring absorbance.Reagents necessary for measurement are inlcuded and subdivided. Begin experiments immediately with simple preparation before measurement.(Please use sonication to dissolve the DPPH Reagent.)
Measuring methodAfter preparing the reagent, add the reagent and sample to the 96-well microplate and react for 30 minutes.
Comparison with a conventional methodWhen measuring antioxidant activity with DPPH, the pH and solvent concentration in the solution affect the measurement. This product uses protocols and analysis methods to minimize these effects.
Effect of pHThe assay buffer provided with the product allows measurement at a certain pH.
Effect of sample solventThe sample volume is set to 1/10 (20 μL) of the total reaction solution. The kit is optimized so that there is no difference in the measured value even if the sample is dissolved in water or ethanol.
IC50 Value VariationIf the antioxidant capacity of a sample is analyzed using only IC50 values, the data will vary slightly in the different measurement conditions. By measuring the sample and standard substance (Trolox) simultaneously and calculating the antioxidant capacity as the Trolox equivalent activity value (TEAC), highly reproducible measurement values can be obtained.TEAC (μg TE/μg) = Trolox IC50 (μg/mL)/ Sample IC50 (μg/mL)”
Measurement ExampleConfirming differences between facilitiesAt three facilities, antioxidants were measured by the DPPH method.Gallic acid, catechin, and morin (known antioxidants) were measured with a spectrophotometer using a cuvette and calculated as a Trolox equivalent activity value (TEAC).There was nearly no difference in measured values between three facilities.Reference: T. Shimamura et al., NipponShokuhin Kagaku Kogaku Kaishi, 2007, 54, 482 – 487.
Comparison between microplate and cuvetteSimilar to the above experiment, three antioxidants were measured using a microplate and calculated as Trolox equivalent activity values. As a result, almost the same measurement results were obtained. This kit uses a microplate for measurement.
This depends on the kit size:
| 100 tests | 500 tests |
|---|---|
| This kit contains enough reagents to measure one 96-well microplate (1 set of DPPH)Analyzing samples and standards in triplicate is recommended for accuracy.Therefore, the number of measurable samples is calculated as follows, assuming that measurement was performed at n: 3.DPPH Reagent per 1 kit is sufficient for 100 tests.Use for 1 sampleOne sample can be measured with the 100 test size kit.Number of wells used during preliminary experiment: Confirmation of optimum concentration range
Sample: 8 (dilution series of 8 points) X 3 (n: 3) = 24 wellBlank: 1 (Blank1) X 3 (n: 3) = 3 well Number of wells used when calculating the IC50 value Sample: 8 (dilution series of 8 points) X 3 (n: 3) = 24 well Trolox: 4 (dilution series of 4 points) X 3 (n: 3) = 12 well Blank: 1 (Blank1) X 3 (n: 3)= 3 well*If there is no require preliminary experiments, the additional sample measurement is possible. |
This kit contains enough reagents to measure 5 96-well microplates (5 sets of DPPH)Choose the quantity used based on your experiment (ex. 500 test x1 or 100 test x5)Up to 8 samples8 samples can be measured with the 500 test size kit.Number of wells during the preliminary experiment: Confirmation of optimum concentration rangeSample: 8 (dilution series of 8 points) X 3 (n: 3) X 8 (8 samples) = 192 wellBlank: 1 (Blank1) X 3 (n: 3) X 3 (3 plates) = 9 wellNumber of wells when calculating IC50 value
Sample: 8 (dilution series of 8 points) X 3 (n: 3) X 8 (8 samples) = 192 welll Trolox: 4 (dilution series of 4 points) X 3 (n: 3) X 5 (5 plates) = 60 well Blank: 1 (Blank1) X 3 (n: 3) X 3 (3 plates) = 9 well |
IC50 value is known: 3 samples・If the IC50 value has already been measured with our kit, 3 samples can be measured with one kit.・If the IC50 value is not measured with our kit, it is recommended to perform a preliminary experiment as an unknown sample.
Number of wells when calculating the IC50 valueSample: 8（dilution series of 8 points) X 3 (n: 3) X 3 (Sample number) = 72 wellTrolox: 4 (dilution series of 4 points) X 3 (n: 3) = 12 wellBlank: 1 (Blank1) X 3 (n: 3) = 3 well