Irvine Chemistry Lab
X-Lyz™ Protein Amine Assay Kit

Quantitation of Unblocked/Reactive Amines

  1. X-Lyz™ Reagent A
  2. X-Lyz™ Reagent B
  3. Norvaline Standard
  4. User Instruction

Please see the MSDS for safely handling.
Contact us for questions, testing services.

  • 15min quick assay
  • Wide linear range
  • Compatible with reducing agents
  • Suitable for microplates and cuvettes
Among the post translational modifications (PTM), the protein amine
(lysine and N-terminus) is one of the most frequently observed PTM
sites. In the case of ubiquitination, the process alters the fate of
proteins by attaching ubiquitin molecules to unblocked amines.  Its
abnormal behavior may serve as a useful biomarker for an early
development of many diseases. During the course of food/feedstuff
processing, on the other hands, the protein amine is commonly
modified by Maillard reaction, that changes the bioavailability of lysine
and compromises its nutritional values.  Therefore, it is necessary to
have a reliable and simple analytical tool to assess the amount of
unblocked and reactive amines in proteins.

The X-Lyz™ Protein Amine Assay Kit is an amine-reactive reagent for
the quantitative determination of amine contents in proteins. The water-
compatible reagent reacts with the primary amines in proteins or
peptides to form a sensitive chromophore; its UV absorbance at
350nm is linearly proportional to the amine concentrations over a wide
analytical range (25-6000nmol/mL of amines, or 25-10,000µg/mL of
proteins;  see Figure 1). The reactive amine amount is quantified
against the standard curve of norvaline.  The assay is simple and
convenient to operate compared to other methods, such as
trinitrobenzenesulfonic acid (TNBS), known as a dangerous explosive
agent.  The X-Lyz™ method is suitable for assays in microplates and
test tubes (cuvettes).  More details may be found in the instruction

Figure 1: Standard Curve of Norvaline Concentration vs.
Absorbance. The assay was conducted in 96-well plate,
WR/Sample 10/1, sample size 25µL.
Catalog #
User Instructions
# of Assays
# of Assays
Test Tube
Download PDF
Download PDF
  Submit purchase orders (PO) to, or order
online below with PayPal or credit
card.  The prices in the table do
not include shipping and taxes, if
applicable. We use FedEx, UPS, or
your preferred shipping carrier.