Non-toxic total nitrogen determination using a low alkaline persulfate digestion

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Biochemistry

Background:

• Accurate measurement of total nitrogen is essential for environmental monitoring and regulatory compliance.
• Traditional methods for total nitrogen analysis are often hazardous, costly, and time-consuming.
• There is a need for a safer, more efficient, and economical method for total nitrogen determination.

Purpose of the Study:

• To develop and validate a novel, eco-friendly method for measuring total nitrogen in water and soil samples.
• To combine alkaline persulfate digestion with a Nitrate Reductase assay for enhanced accuracy and efficiency.
• To provide a cost-effective alternative to existing hazardous methods for total nitrogen analysis.

Main Methods:

• Samples undergo alkaline persulfate digestion to oxidize all nitrogenous compounds to nitrate.
• Nitrate is then reduced to nitrite using Nitrate Reductase and nicotinamide adenine dinucleotide (NADH).
• Nitrite is quantified colorimetrically using Griess reagents, with absorbance measured at 540 nm.

Main Results:

• The combined method accurately determines total nitrogen content by comparing sample absorbance to a nitrate standard curve.
• This enzymatic approach offers a greener alternative, avoiding hazardous reagents and complex procedures.
• The method demonstrates customization for total nitrogen analysis through a sensitive colorimetric detection.

Conclusions:

• The developed method provides a safe, efficient, and cost-effective means for total nitrogen measurement in environmental samples.
• This green chemistry approach utilizing alkaline persulfate digestion and Nitrate Reductase assay is suitable for routine analysis.
• The method enhances water and soil quality monitoring by offering a reliable and accessible analytical tool.