Micro-Biological Evidence Extraction: Operating Guidelines

This article outlines operating guidelines for micro-biological evidence extraction solutions, ensuring safe, efficient microbial sample recovery while preserving evidence integrity.

Core Operating Steps

  1. Solution Preparation: Dilute concentrated extraction solution per instructions (e.g., 1:10 with sterile PBS); verify pH (7.2–7.4) and sterility via visual check.
  2. Sample Application: Apply 500–1000μL solution to evidence (swabs, surfaces); incubate at 25–37°C for 10–15 mins to loosen microbes.
  3. Extraction: Vortex swabs or scrape surface solution into sterile tubes; centrifuge at 3000×g for 5 mins to pellet microbes.
  4. Post-Extraction Handling: Discard supernatant; resuspend pellet in 200μL storage buffer; label tubes with evidence ID and process immediately or store at -80°C.

Key Precautions

  • Use sterile tools/solutions to avoid cross-contamination of microbial samples.
  • Wear PPE (gloves, mask, lab coat) to prevent exposure to biohazards.
  • Do not exceed incubation time/temp—avoids microbial cell lysis.
  • Follow disposal protocols for used solutions/tubes as biohazardous waste.

Solution Features

  • Microbe-Friendly: Gentle formula preserves microbial viability for culture/sequencing.
  • Efficient: Breaks down organic debris without damaging microbial cells.
  • Stable: Shelf-stable for 6 months when stored at 2–8°C, no frequent reconstitution needed.

Application Scope

  • Forensics: Extracting bacteria/fungi from crime scene evidence (weapons, clothing, surfaces).
  • Clinical Labs: Recovering microbial pathogens from patient samples (wounds, swabs).
  • Environmental Testing: Extracting microbes from environmental evidence (soil, water) in contamination cases.