Grantee Research Project Results

Final Report: Development of a Near-Real-Time Analytical System for Measurement of N-nitrosamines in Water Reuse

EPA Contract Number: 68HERC22C0034
Title: Development of a Near-Real-Time Analytical System for Measurement of N-nitrosamines in Water Reuse
Investigators: Griffiths, Duncan
Small Business: Hyperion Analytical LLC
EPA Contact: Richards, April
Phase: II
Project Period: January 1, 2022 through December 31, 2023 (Extended to December 31, 2024)
RFA: Small Business Innovation Research (SBIR) Phase II (2022) Recipients Lists
Research Category: SBIR - Water , Small Business Innovation Research (SBIR)

Description:

This project successfully developed two versions of an analytical instrument for the measurement of Nnitrosamines in recycled water and other sample matrices. From earlier proof of concept work published in the scientific literature and the Phase I project, the analytical technique and engineering  implementation was refined using both commercial components and bespoke manufactured components to improve performance. Software was developed to control the hardware and to analyze the data without requiring expensive commercial software packages.

The first configuration was to using a standard HPLC front end for a laboratory-based prototype system along with the multi-step sample conditioning and detector system. The second configuration was a fully automated and integrated system that could be operated in a continuous-operation, unattended, online configuration. These systems were targeted to have unparalleled detection performance at a fraction of the cost of the current standard mass spectrometry based analytical systems.

Summary/Accomplishments (Outputs/Outcomes):

Measurement performance for a number of different nitrosamines samples proved to be excellent with detection limit below one nanogram per liter. Well defined sample signals were obtained on a number of different nitrosamine species from the single ng/L range up to 100 nanograms per liter with excellent linearity and precision. Mixed samples of multiple nitrosamines were easily resolved by the well-refined chromatographic method. Other sample types were evaluated and can easily be accommodated on the same instrument.

Both configurations of the system were shown to have equivalent measurement performance. The online system was constructed using commercially available components that are well tested in the field. Fully automated around the clock testing was routinely and easily achieved from a simulated process line. Field testing needs to account for variations in the sample conditions and pretreatment requirements.

The laboratory HPLC-based system was designed and devaluated with two different HPLC systems. In both cases the integration and measurement performance was excellent. This will be suitable for facilities that want to add detector system to an existing HPLC that they have available or where there is a preference for laboratory based testing rather than online.

Extensive refinement of the basic technique has shown several avenues for further improvement of the sensitivity and resolution of mixed samples. Consultation with relevant vendors or technical experts provided useful input and guided those future development paths.

Conclusions:

The work carried out proves our HPLC-chemiluminescence technique is capable of measurement 
performance that is competitive with current commercial offerings. Furthermore, the system can be 
built either as an accessory to an existing HPLC system or a complete integrated system for fully 
automated online analysis. Further refinement and optimization is needed to find the limits of the 
technique and to fully characterize all measurement parameters. 

No publications were generated as a result of this Phase II activity, although the successful results of testing have received positive feedback from private consultations with experts in the field. Our development data will be written up to apply for a presentation at upcoming conferences.

The result of this Phase II project is two working prototypes that are capable of routine testing and high sensitivity. The current systems have bespoke software that has automated the testing workflow and provided data analysis capabilities. Ongoing engineering work will improve the level of robustness and automation of the technique to market requirements. Our approach is to offer a complete system without requiring an outside vendor or software package.

The results generated show the potential of our technical approach and conversations with potential commercial partners and end users confirm the high level of interest from the marketplace for this costeffective and capable analytical tool. Besides having equivalent, or potentially better, measurement performance to the mass spectrometry-based systems costing 3-5 times as much, the ability to operate online and unattended enhances the market appeal greatly. Further engineering development will result in a robust and user-friendly product that will meet market requirements.

Further funding will be sought to continue the development and launch the products on the market.

SBIR Phase I:

Development of a near-real-time analytical system for measurement of N-nitrosamines in water reuse  | Final Report