1. 334 Hecla Street, Lake Linden, MI 49945
tech@nitrate.com | 1.906.296.1130
sales@nitrate.com | 1.906.296.1115
www.nitrate.com
Specificity:
Sensitivity:
Analysis Ranges:
Sample Types:
Storage Conditions:
Active Temperature Range:
Buffer Specifications:
Enzymatic Orthophosphate Test
NECi’s Enzymatic Orthophosphate Test is a highly specific, sensitive and
selective assay for the quantitative analysis of soluble reactive phosphate
(SRP) in many types of sample matrices.
Quantitative orthophosphate analysis is useful for evaluating soil health,
environmental health, industry process control, wastewater nutrient
levels, and much more.
This method is compatible with the persulfate digestion for total
phosphorus analysis. Total P kits based on the USGS method will be
available soon.
Utilizes a recombinant enzyme Purine nucleoside phosphorylase
(PNP) to catalyze the reaction of phosphate with substrate
2-amino-6-mercapto-7-methylpurine ribonucleoside (MESG). The
resulting 2-amino-6-mercapto-7-methylpurine (AMMP) absorbs
at 360 nm for accurate photometric analysis of phosphate.
Replaces the ascorbic acid method for more precise analysis.
Results in phosphorus units are obtainable with a simple
conversion factor.
Small reaction volume, minimal sample preparation, &
non-hazardous materials or waste.
Available in test tube, microplate, & on-site formats or
build your own assay with enzyme reagent packs.
Orthophosphate
15 - 40 °C
200 mM HEPES | 20 mM MgCl2
pH 7.6
Water
Soil
Aqueous Extracts
Low: 0.5 - 5.0 ppm
Standard: 5.0 - 20.0 ppm
0.5 ppm MDL
3+ Years @ -80°C
1+ Year @ -20°C
6 Months @ 4°C

2. 334 Hecla Street, Lake Linden, MI 49945
tech@nitrate.com | 1.906.296.1130
sales@nitrate.com | 1.906.296.1115
A Closer Look at the Reaction
Overview of the Method
Example Standard Curve
H2PO4
-
2-amino-6-mercapto-7-methylpurine ribonucleoside
+
2-amino-6-mercapto-7-methylpurine
Purine Nucleoside
Phosphorylase
MESG
Ribose-1-phosphate
+
Wait
10 Min
900 µL
Reaction
Mixture
Combine Reaction Mixture
+ Sample into test tube
100 µL
Sample
Fill to
20.5 mL
with
Buffer
Prepare Stock
Reaction Mixture
1 mL
PNP
1 mL
MESG
By using a set of phosphate standards of known
concentration, a standard curve is used to
calibrate the method and quantify phosphate
content of unknown samples.
When used in conjunction with NECi’s Handheld
Photometer, results can be obtained on any
Android mobile device. The app software has a
pre-programmed standard curve and displays
data in ppm phosphate.
Measure A-360 of each sample
in UV compatible cuvettes
Note: ppm Phosphate x 0.3262 = ppm Phosphorus
Order online at nitrate.com/store/index.php/phosphate