Rapid Ultrasensitive and High-Throughput Bioburden Detection: Microfluidics and Instrumentation.

Area of Science:

• Biotechnology
• Analytical Chemistry
• Microbiology

Background:

• Traditional bioburden detection methods rely on lengthy culturing, hindering rapid contamination assessment.
• There is a need for sensitive, fast, and cost-effective methods to detect low-level microbial contamination.

Purpose of the Study:

• To develop and validate a microfluidic system coupled with a multichannel fluorometer for enhanced bioburden detection.
• To decrease the limit of detection (LOD) and increase the rate of contamination detection.

Main Methods:

• A microfluidic cassette and an eight-channel fluorometer were employed for parallel sample analysis.
• The redox indicator dye resazurin was used to monitor viable cells, with fluorescence intensity changes measured at 585 nm.
• The assay was optimized using Luria-Bertani medium and validated against a spectrophotometer using *Escherichia coli*.

Main Results:

• The system achieved a limit of detection (LOD) as low as <1 cfu/mL.
• Detection of bioburden was achieved in as little as 20 seconds for concentrations ≥5 cfu/mL after 6 hours of incubation.
• The system demonstrated sensitivity by detecting inadvertent contamination from lab consumables.

Conclusions:

• The developed microfluidic multichannel fluorometer system provides a portable, low-cost, and simple solution for rapid bioburden detection.
• This system is suitable for diverse settings including laboratories, pharmaceutical manufacturing, and field applications.
• The technology offers comparable performance to conventional plate readers with significantly improved detection speed and sensitivity.