Lactate Dehydrogenase (LDH) Activity Assay Kit (WST-8 method)

Lactate Dehydrogenase (LDH) Activity Assay Kit (WST-8 method)

SKU #	E-BC-K766-M
Detection Instrument	Microplate reader (450 nm)
Detection method:	Colorimetric method

Product Details

Properties

Synonyms	LDH
Sample type	Serum, plasma, animal tissue, hydrothorax, cells, cell culture supernatant
Sensitivity	0.11 U/L
Detection range	0.11-39.9 U/L
Detection method	Colorimetric method
Assay type	Enzyme Activity
Assay time	30 min
Precision	Average inter-assay CV: 2.300% | Average intra-assay CV: 2.300%
Other instruments required	Microplate, Micropipettor, Vortex mixer, Water bath
Storage	-20℃
Valid period	12 months

Images

Dilution of Sample

 

It is recommended to take 2~3 samples with expected large difference to do pre-experiment before formal experiment and dilute the sample according to the result of the pre-experiment and the detection range (0.11-39.9 U/L).

The recommended dilution factor for different samples is as follows (for reference only):

Sample type	Dilution factor
Human serum	10-20
Dog serum	10-20
Mouse serum	50-100
Cynomolgus monkey serum	10-20
10% Rat spleen tissue homogenate	150-250
10% Rat liver tissue homogenate	250-350
10% Rat kidney tissue homogenate	250-350
10% Rat lung tissue homogenate	250-350

 

Note: The diluent is reagent 1.

 

Detection Principle

Lactate dehydrogenase (LDH) is an oxidoreductase. LDH catalyzes the conversion of lactate to pyruvic acid and back, as it converts NAD+ to NADH and back. LDH is composed of four subunits (tetramer). The two most common subunits are the LDH-M and LDH-H protein. LDH is released into the blood by cells after tissue damage or erythrocyte hemolysis. Extracellular LDH activity is used to detect cell damage or cell death.

 

Kit Components & Storage

Item	Component	Size 1(48 T)	Size 2(96 T)	Storage
Reagent 1	Lysis Solution	60 mL × 1 vial	60 mL × 2 vials	-20℃, 12 months
Reagent 2	Substrate	1.5 mL ×1 vial	1.5 mL × 2 vials	-20℃, 12 months
Reagent 3	Chromogenic Agent	1.5 mL ×1 vial	1.5 mL × 2 vials	-20℃, 12 months, shading light
Reagent 4	Coenzyme	Powder × 1 vial	Powder × 1 vial	-20℃, 12 months
Reagent 5	Stop Solution	3 mL ×1 vial	6 mL ×1 vial	-20℃, 12 months
Reagent 6	NADH Standard	Powder × 1 vial	Powder × 1 vial	-20℃, 12 months
	Microplate	96 wells	No requirement
	Plate Sealer	2 pieces

 

Note: The reagents must be stored strictly according to the preservation conditions in the above table. The reagents in different kits cannot be mixed with each other. For a small volume of reagents, please centrifuge before use, so as not to obtain sufficient amount of reagents.

 

Technical Data:

Parameter:

Intra-assay Precision

Three human serum samples were assayed in replicates of 20 to determine precision within an assay (CV = Coefficient of Variation).

Parameters	Sample 1	Sample 2	Sample 3
Mean (U/L)	2.60	18.50	26.00
%CV	2.6	2.3	2.0

Inter-assay Precision

Three human serum samples were assayed 20 times in duplicate by three operators to determine precision between assays.

Parameters	Sample 1	Sample 2	Sample 3
Mean (U/L)	2.60	18.50	26.00
%CV	2.4	2.5	2.0

Sensitivity

The analytical sensitivity of the assay is 0.11 U/L. This was determined by adding two standard deviations to the mean O.D. obtained when the zero standard was assayed 20 times, and calculating the corresponding concentration.

 

Standard Curve

As the OD value of the standard curve may vary according to the conditions of the actual assay performance (e.g. operator, pipetting technique or temperature effects), so the standard curve and data are provided as below for reference only:

Concentration (μmol/L)	0	50	100	150	200	250	300	400
Average OD	0.054	0.171	0.292	0.430	0.559	0.691	0.845	1.114
Absoluted OD	0.000	0.117	0.238	0.377	0.505	0.638	0.792	1.061