As part of my Te Ahikawariki/Vegetable Industry Centre of Excellence (VICE) internship I have been helping Dan run workshops in Pukekohe, Palmerston North/Levin and Gisborne. As apart of these workshops we have been demonstrating how to use a Nitrachek device.
The Nitrachek device produces a nitrate parts per million (ppm) result based on the colour of a nitrate test strip. The Nitrachek is designed to use the MQuant Nitrate test strips to produce an accurate reading.
There is an international shortage of MQuant nitrate test strips at present, so we wanted to know if Quantofix test strips can be used instead.
The Quantofix test strips were compared to the MQuant test strips in the Nitrachek (set to lot 5) using nitrate solutions with different concentrations: 500, 250, 125, 62.5, 31.25, 15.63, and 7.81 ppm.
The Quantofix Nitrachek readings were much lower than the MQuant Nitrachek readings.
Quantofix vs MQuant Nitrachek readings on lot 5.
| Solution (ppm) | Quantofix Nitrachek reading (ppm) Lot 5 | MQuant Nitrachek reading (ppm) Lot 5 |
| 500 | 221 | 488 |
| 250 | 111 | 236 |
| 125 | 58 | 135 |
| 62.5 | 31 | 70 |
| 31.25 | 16 | 32 |
| 15.63 | 10 | 18 |
| 7.81 | 7 | 8 |
Conclusion
Based on the trend line equation, it was determined the Quantofix test strips can be used in the Nitrachek device on lot 5 and can be corrected by multiplying the Nitrachek ppm reading by 2.2. This will produce a similar result to a Nitrachek reading on lot 5 with a MQuant nitrate test strip.
– Olivia