A Microfabricated, Flow-Driven Grinding Mill for Mechanical Cell Lysing.

Area of Science:

• Biotechnology and Biomedical Engineering
• Marine Biology and Ecotoxicology

Background:

• Alexandrium algae produce neurotoxins responsible for red tide and paralytic shellfish poisoning.
• Efficient lysis of robust algal cells is crucial for accurate detection and downstream bioanalysis.
• Current lysis methods often involve harsh chemicals that can interfere with analyses.

Purpose of the Study:

• To design, microfabricate, and demonstrate a novel microfluidic grinding mill for algal cell lysis.
• To achieve efficient lysis of Alexandrium cells using mechanical abrasion.
• To provide a lysis method compatible with downstream molecular analyses.

Main Methods:

• Development of a microfluidic device featuring a high-speed, hydrodynamically driven microrotor.
• Integration of the microrotor with a micro grinding mill for mechanical cell disruption.
• Validation of lysis efficiency and cytoplasm release using polymerase chain reaction (PCR).

Main Results:

• The microfluidic grinding mill achieved single-pass lysis efficiencies as high as 97% for Alexandrium cells.
• Mechanical abrasion effectively lysed robust algal cells without chemical additives.
• Successful PCR amplification of Alexandrium DNA confirmed cytoplasm release, validating the method.

Conclusions:

• The novel microfluidic grinding mill offers a highly efficient and non-chemical method for lysing Alexandrium.
• This technology presents a viable alternative to existing lysis techniques, minimizing interference with downstream assays.
• The device facilitates improved detection of harmful algae and associated toxins.