Lowry Protein Quantification Assay Kit

Catalog No. ABIN3172698

Product Details

Detection Method: Colorimetric

Detection Range: 1-1500 μg/mL

Minimum Detection Limit: 1 μg/mL

Application: Quantification (Q)

Purpose: The kit is designed for protein quantification in biological samples.

Sample Type: Plasma, Tissue Homogenate, Urine, Serum, Cell Lysate

Analytical Method: Quantitative

Specificity: Specific for protein quantification.

Characteristics: Lowry Protein Quantification Assay is based on Lowry method1, first described in 1951. The method relies on two different reactions. The first is the formation of a copper ion complex with amide bonds, forming reduced copper in alkaline solutions. This is

Components: Plate and the reagents neccesary to perform the assay.

Material not included: Pipettes, reaction tubes, plate reader, centrifuge.

Application Details

Comment:

1ml (microassay)/ 40μL (microplate)

Assay Time: 1 h

Plate: Uncoated

Reagent Preparation:

Lowry Assay Mix: Mix Lowry Reagent A with Lowry Reagent B in a ratio 1:100. Prepare fresh daily.
Lowry Working Solution: Dilute Lowry Reagent C with an equal volume of water to prepare the desired volume. Prepare diluted reagent fresh daily.

Assay Procedure:

MICROASSAY: 1. Pipette1 mL of each standard or unknown sample solution into separate clean test tubes. Refer to the Table 2 as a guide for diluting the protein standard (see kit book let). For the diluents, use the same buffer as in the samples. 2.To each tube, add 5 mL of freshly prepared Lowry assay mix and thoroughly vortex. 3.Incubate tubes 10 min at room temperature. 4.Add 0.5 mL of Lowry Working Solution to each tube and vortex immediately. 5.Incubate 30 min at room temperature. 6.Vortex the tubes, zero the spectrophotometer with the blank, and measure the absorbance at 660 nm.
MICROPLATE: 1. Pipette 40 μL of each standard and unknown sample replicate into a microplate well. Refer to the Table 3 as a guide for diluting the protein standard (see kit book let). For the diluents, use the same buffer as in the samples. 2.Add 200 μL of freshly prepared Lowry Assay Mix and immediately mix the microplate for 30 seconds. 3.Incubate microplate exactly 10 min at room temperature. 4.Add 20 μL of freshly prepared Lowry Working Solution to each well and immediately mix the microplate for 30 seconds. 5.Incubate 30 min at room temperature. Measure the absorbance at 660 nm on a plate reader.

Calculation of Results:

1.If the spectrophotometer or microplate reader was not zeroed with the blank, then average the blank values and substract the average blank value from the standard and unknown sample values. 2.Create a standard curve by plotting A660nm (y-axis) vs BSA standard (μg) (x-axis). Determine the unknown sample concentration using the standard curve . 3.The level of detection of the assay is lower for the microplate assay when compared with the microassay due to a shorter light path used in the microplate reader. 4.Standard curve example for microplate assay procedure is shown in Figure 2 (see Images). A sample Lowry protein assay standard curve produced using BSA at triplicate points in a range of 5 to 280 μg is shown in Figure 3 (see images). The data are fit with a polynomic regression.

Restrictions: For Research Use only

Handling

Preservative: Sodium azide

Precaution of Use: This product contains Sodium azide: a POISONOUS AND HAZARDOUS SUBSTANCE which should be handled by trained staff only.

Storage: 4 °C