Creatine Amidinohydrolase

Product Overview

Creatinine (CREA) is a key indicator for assessing renal function; in China, it is measured more than 2 billion times annually, second only to blood glucose. Creatine amidohydrolase (abbreviated as CR) is the rate-limiting enzyme in enzymatic creatinine assay kits. CR specifically catalyzes the hydrolysis of creatine into sarcosine and urea; however, wild-type CR exhibits low catalytic activity and poor stability.

Through directed enzyme engineering, we have optimized its Km value and thermal stability, significantly improving the precision of low-concentration sample detection.

This product has been specially developed for clinical precision creatinine testing, maintaining stable activity across a broad pH range of 4.5–10.0 and demonstrating excellent tolerance to 50℃ conditions. It can be used upstream to eliminate endogenous creatine interference in samples, thereby preventing misinterpretation of borderline cases.

The product is compatible with combined renal function biochemical assays, two-reagent diagnostic systems, and mass-produced POCT biosensor test strips for kidney disease, and exhibits outstanding synergistic performance when paired with CAH, SOX, CAT, and POD enzymes. It is also fully compatible with mainstream global clinical biochemistry platforms.

Key Features

Enhanced Low-End Sensitivity via Lower Km

A lower Km value enhances the reagent's low-end sensitivity and reduces the need for manual judgment of borderline samples.

Ultra-Wide pH Stability (4.0–11.0)

Ultra-wide stability range of pH 4.0–11.0, with high compatibility with creatinine assay systems and greater flexibility for reagent optimization.

Improved Stability and Extended Shelf Life

Better stability and a longer shelf life, ensuring reliable reagent stability.

Excellent Batch-to-Batch Consistency Through Strict QC

Strict quality control, including for miscellaneous enzymes, ensures excellent batch-to-batch consistency in reagent validation.

Parameter	Hzymes	Vendor A	Vendor B
Specific activity (U/mg)	12.0	12.3	16.0
Km（Creatine）	8.8mM	19.0mM	13.0mM
Optimal temperature（℃）	45	40	40
Optimal pH	7.0-9.0	8.0	7.0-9.0
Thermal stability (30 min)	≤50℃	≤50℃	≤40℃
pH stability (25℃, 24hr)	4.0-11.0	5.5-9.0	5.5-11.0
Half-life（min）	11.37	10.17	6.52
Contaminants	CNH≤0.01%; SOX≤0.01%; CAT≤0.03%; NOX≤0.01%; LOX: Residue-free	CAT≤2%、NOX≤0.05	N/A

Applications

Core applications: Hydrolyzed creatine, in combination with CAH (catalog no. HH0106), SOX (catalog no. HH0301), and CAT (catalog no. HH2901), is used for the development and large-scale preparation of enzymatic creatinine reagents.

Reaction Principle

The amount of the yellow dye formed by the reaction of urea with DAB (ρ-dimethylaminobenzaldehyde) can be measured spectrophotometrically at 435 nm. One unit of enzyme activity is defined as the amount of enzyme required to catalyze the complete conversion of 1μmol of creatine to sarcosine per minute at 37℃.

Specification

CAS	37340-58-2
EC Number	EC 3.5.3.3
Appearance	White amorphous lyophilized powder
Dry powder specific activity	≥5.8U/mg
Protein Purity	≥90%（SDS-PAGE）
Contaminants	Catalase≤0.03%；Creatininase amidohydrolase≤0.01%；Sarcosine oxidase≤0.01%；NADH oxidase≤0.01%
Protectants	EDTA and carbohydrate substances
Optimal pH	8.0
pH stability	pH4.5-10.0（25℃，16h）
Optimal temperature	45℃
Temperature stability	Below 50℃（pH7.5，30min）
Long-term stability	Store at -25 to -15°C for 12 months, maintaining over 90% activity.
Km	8.81×10-3 M (Creatinine)
MW	48 kDa（SDS-PAGE）
pI	4.6
Inhibitors	Ag⁺，Cu²⁺，Hg²⁺

Available Formats

✧ HH0203-01 5kU

✧ HH0203-02 100kU

✧ HH0203-03 500kU

✧ HH0203-04 1000kU

✧ HH0203-99 Customizable

Performance Data

Wide Linear Range with Excellent Method Correlation

Wide linear range, with excellent correlation between measured values in blood and urine samples and those obtained using reagents from leading manufacturers, and a bias of less than 5%.