Apollo Scientific™ (2-Nitrophenyl)-β-D-galactopyranoside (ONPG) ≥99%

The Apollo Scientific™ ONPG (o-Nitrophenyl-β-D-galactopyranoside) is a high-purity (≥99%) chromogenic substrate widely used for the detection and quantification of β-galactosidase activity in microbiology and molecular biology applications. ONPG serves as a reliable alternative to lactose in enzymatic assays, enabling rapid and sensitive identification of β-galactosidase-producing organisms.

Upon enzymatic hydrolysis, ONPG is cleaved at the β-1,4-glycosidic bond, releasing o-nitrophenol, a yellow-colored compound that can be easily measured using colorimetric or spectrophotometric methods. This clear and quantifiable color change makes ONPG an essential reagent for enzyme activity assays, bacterial identification, and genetic studies.

Key Features

• High purity (≥99%) for accurate and reproducible results
• Chromogenic substrate for β-galactosidase detection
• Produces yellow o-nitrophenol upon enzymatic cleavage
• Suitable for colorimetric and spectrophotometric assays
• Ideal for rapid lactose fermentation and coliform detection workflows
• High-quality reagent from Apollo Scientific™
• Available in multiple pack sizes for laboratory flexibility

Applications

• Detection of β-galactosidase activity
• Identification of lactose-fermenting bacteria
• ONPG test for coliform bacteria detection
• Molecular biology and gene expression studies (lac operon systems)
• Enzyme kinetics and biochemical assays
• Clinical and food microbiology testing
• Water quality and environmental monitoring

Principle of the Method

ONPG acts as a synthetic substrate for β-galactosidase:

• The enzyme hydrolyzes ONPG at the β-1,4-glycosidic bond
• This releases o-nitrophenol, which produces a yellow color
• The intensity of the yellow color is proportional to enzyme activity
• Results can be measured visually or via spectrophotometry

Technical Specifications

Available Pack Sizes

Advantages

The Apollo Scientific™ ONPG substrate offers high sensitivity and rapid detection, making it a preferred reagent for β-galactosidase assays. Its clear colorimetric response allows straightforward interpretation without complex instrumentation, while its high purity ensures consistent and reliable analytical performance.

Compared to traditional lactose-based tests, ONPG provides faster and more definitive results, improving workflow efficiency in both research and diagnostic laboratories.

The Apollo Scientific™ ONPG (≥99%) is a versatile and high-performance chromogenic substrate for β-galactosidase detection and microbial identification. With its excellent sensitivity, ease of use, and broad applicability, it is an essential reagent for laboratories engaged in microbiology, molecular biology, and biochemical analysis.