Product Overview

Malate Dehydrogenase (MDH) catalyzes the reversible reaction between oxaloacetate and NADH, producing Lmalate and NAD⁺. Substrate changes can be quantified by monitoring absorbance at the characteristic 340nm wavelength of NADH. In the IVD field, MDH serves as a key component in aspartate aminotransferase/glutamic oxaloacetic transaminase (AST/GOT) assay kits and carbon dioxide (CO₂) assay kits. Addressing practical needs arising from AST and CO₂ kit development, Hzymes has engineered a recombinant MDH (HH1802) through gene mining, process optimization, and rigorous testing, with all core performance parameters thoroughly validated. Production processes are tightly controlled, ensuring minimal batch-to-batch variability. The electrophoretic purity of this MDH exceeds 90%, exhibiting high affinity for both oxaloacetate and NADH, while endogenous contaminant levels remain wellcontrolled. Its specific activity--both in solution and as a lyophilized powder--is significantly higher than that of leading international competitors. The enzyme remains stable below 50°C and is compatible across a broad range of biochemical reagent formulations (pH4.0-9.0), thereby enhancing the performance of AST and CO₂ assay kits. MDH (HH1802) is now manufactured on an industrial scale, available in multiple volume tiers, and can be flexibly customized to support in vitro diagnostic reagent registration submissions as well as tailored formulation development for domestic and international IVD manufacturers.

Key Features

High Specific Activity Enables Lower Enzyme Usage

The specific activity of the enzyme powder is significantly higher than that of well-known brands; at the same enzymeloading level, it requires a lower dosage, thereby minimizing interference with the assay system.

Robust Manufacturing for Excellent Batch-to-Batch Consistency

The manufacturing process is robust, with minimal batch-to-batch variability in both enzyme solution and lyophilized powder, facilitating consistent control of interbatch differences in the reagent.

Applications

Liver function-AST assay:

MDH (HH1802) is primarily used for the development and large-scale preparation of aspartate aminotransferase/glutamic oxaloacetic transaminase (AST/GOT) assay kits.

CO₂ assay:

MDH (HH1802), in combination with phosphoenolpyruvate carboxylase (PEPC, HH1902), is employed in the development and large-scale production of carbon dioxide assay reagents.

Metabolite analysis:

MDH can also be used to measure malic acid or oxaloacetic acid concentrations in serum, cells, and tissues, facilitating the assessment of gluconeogenesis and the tricarboxylic acid cycle.

Reaction Principle

The amount of NADH can be measured at 340nm. One unit of enzyme activity is defined as the amount of enzyme required to consume 1μmol of NADH per minute under reaction conditions of pH7.5 and 37°C.

Specification

Available Formats

• HH1802-01 20kU

• HH1802-02 100kU

• HH1802-03 1000kU

• HH1802-99 Customizable

Performance Data

R > 0.99 Correlation with Leading Commercial Reagents

Maintains Accuracy After 10-Day Accelerated Aging at 37°C

MDH (HH1802) uses an aspartate aminotransferase/glutamic oxaloacetic transaminase (AST/GOT) assay reagent, whose measurement results show excellent correlation with those obtained using reagents from well-known manufacturers (R > 0.99). After 10 days of accelerated testing at 37°C, the reagent’s accuracy remained acceptable, with deviations from the target values of the quality control materials within ±20%.

Validated for Single-Reagent CO₂ Assay Applications

MDH (HH1802) is designed for use with a singlereagent CO₂ assay and has undergone rigorous empirical validation, demonstrating excellent performance across all parameters and fully meeting the requirements for kit registration, preparation, and application.

Broad Linear Range with Excellent Linearity

The CO₂ reagent exhibits a broad linear range: measured values from 0 to 57 mM show strong correlation with fitted values (R > 0.990).

High Accuracy and Precision with Strong Method Correlation

It balances methodological accuracy with that of internationally imported brands: quality control results remain within target ranges; intrabatch precision (CV) is 1%; and measurements before and after accelerated storage demonstrate high correlation with competing products (R > 0.990), accompanied by small biases (≤10 mmol/L, |B|MAX ≤ 1; >10 mmol/L, |B%|MAX ≤ 10%; average bias <5%).

Outstanding Resistance to Common Serum Interferents

Outstanding antiinterference performance: the reagent tolerates common serum interferents such as hemoglobin (≤800mg/dL), bilirubin (≤80mg/dL), vitamin C (≤60mg/dL), and chylomicrons (≤1000 mg/dL), with measurement deviations consistently ≤±5.0%.