Towards ultra-sensitive and rapid near-source wastewater-based epidemiology

Area of Science:

• Environmental science
• Nanotechnology
• Public health

Background:

• Wastewater-based epidemiology (WBE) is a valuable public health surveillance tool.
• Current PCR methods have long delays (24-72 hours) due to lab transport.
• Existing rapid tests, like gold nanoparticle dipsticks, lack sensitivity for wastewater.

Purpose of the Study:

• To develop rapid, near-source WBE tests using nanomaterials.
• To overcome limitations of current PCR and nanoparticle dipsticks.
• To establish early-warning sensors for infectious diseases in wastewater.

Main Methods:

• Explored visually-read carbon black dipsticks.
• Developed spin-enhanced fluorescent nanodiamond dipsticks for selective separation.
• Achieved a 2-hour turnaround time with minimal equipment.
• Tested raw, unprocessed wastewater samples in a proof-of-concept 'lab-in-a-suitcase'.

Main Results:

• Carbon black dipsticks showed 80% sensitivity and 100% specificity.
• Nanodiamond dipsticks achieved 100% sensitivity and specificity.
• Assay limit of detection reached 7 copies per sample.
• Demonstrated a 2-hour sample-to-result time.

Conclusions:

• Developed sensitive and specific nanomaterial-based dipsticks for near-source WBE.
• Nanodiamonds offer superior performance by separating from background autofluorescence.
• Findings support the development of portable, early-warning quantum sensors for environmental public health surveillance.