Food Safety and Nutrient Detection

Homocysteine Assay Kit allows for quantification of total homocysteine in biological fluids such as plasma and serum. The assay is based on the reduction of homocysteine disulfides to free homocysteine, which is cleaved by a homocysteine-selective enzyme, generating an intermediate product. The intermediate reacts with a probe solution to form a stable fluorophore that emits in the far-red spectrum (Ex/Em = 658/708 nm). The assay is not affected by physiological concentrations of other biological thiols (such as cysteine, methionine and glutathione), is high-throughput adaptable and can detect as low as 5 μM homocysteine.

Hydroxyproline Assay Kit II (Perchlorate-Free) uses a proprietary acidic developer solution to accurately measure Hyp in tissue and protein/peptidase hydrolysates without the use of hazardous perchlorates. It is a quick and convenient protocol, yielding a brightly-colored chromophore with an absorbance peak at 560 nm. The assay can detect a minimum of 0.05 µg hydroxyproline per well in a 96-well format and generates colorimetric results that are virtually identical to the classical perchloric acid-based method.

Hydroxyproline Assay Kit is designed to measure hydroxyproline in tissue or protein/peptide hydrolysates. It can be used to measure hydroxyproline from other biological samples such as serum or urine if they have undergone a prior purification process. It is an easy, convenient method which results in a chromogen with an absorbance maximum at 560 nm. The assay is useful over the range of 0.1-2 μg.

Invertase Activity Assay kit provides a simple, sensitive and high-throughput adaptable assay that detects relevant concentrations of Invertase in biological samples or purified/crude enzyme preparations. The assay is based on the enzymatic detection of glucose, one of the hydrolysis products. Detection limit: 20 µU.

There is no requirement for sample pretreatmen or purification when using this kit. The L-amino acid(s) level can be quantified using fluorometric (at Ex/Em = 535/587 nm) or colorimetric (at λ = 570 nm) methods in 96-well plates.

Methionine Assay Kit utilizes an enzymatic mechanism by which metabolism of methionine is coupled with the stoichiometric generation of hydrogen peroxide. A probe generates fluorometric signal that can be quantified at Ex/Em: 535/587 nm. The assay shows greater than 10-fold specificity for methionine over cysteine and greater than 40-fold selectivity over other standard and non-standard amino acids. After utilization of a proprietary Sample Clean-Up Mix, the method is suitable for use in blood samples, and can detect concentrations as low as 0.5 µM, or 25 pmole Methionine.

The NAD Cycling Enzyme Mix in the kit specifically recognizes NADH/NAD in an enzyme cycling reaction. There is no requirement to purify NADH/NAD from samples. The reaction specifically detects NADH and NAD, but not NADP nor NADPH. The enzyme cycling reaction significantly increases the detection sensitivity and specificity. NADt (NAD and NADH) or NADH can be easily quantified by comparing with standard NADH.

Nitric Oxide Fluorometric Assay Kit provides an accurate and convenient measurement of total nitrate/nitrite concentration in a simple two-step process. In the first step nitrate is converted to nitrite by nitrate reductase. In the second step, nitrite reacts with the fluorescent probe DAN (2, 3 diaminonaphthalene). NaOH enhances the fluorescent yield. The fluorescent intensity is proportional to the total nitric oxide production. The kit has been tested with culture media, plasma, and tissue homogenates.

Oxaloacetate Assay Kit provides a simple, sensitive and rapid means of quantifying OAA in a variety of samples. In the assay, OAA is converted to pyruvate which is utilized to convert a nearly colorless probe to an intensely colored (λmax= 570nm) and fluorescent (Ex/Em = 535/587nm) product. The Oxaloacetate Assay Kit can detect 0.1-10nmol (2-200 µM) of OAA.

Phenylalanine Assay Kit provides a quick, simple, accurate method for quantifying PHE in biological samples. In the assay, PHE is reductively deaminated with the simultaneous formation of NADH which reacts with our fluorescent probe to generate fluorescence at Ex/Em=535/587 nm. The assay is linear in the range from 0.1 to 1.0 nmol (2-20 µM) of Phenylalanine.