Laboratory Practice
Efficient and compliant laboratory operations are the foundation of accurate cytogenetic testing. This involves rigorous sample tracking, chemical safety, equipment maintenance, and adherence to retention regulations
Label Specimens
- Two-Identifier Rule: Every container (tube, flask, slide) must have at least two unique identifiers (Name + MRN/DOB)
- Chain of Custody: Samples are split into multiple cultures. All daughter vessels must be labeled with the Accession Number and Culture ID (e.g., Flask A vs. Flask B)
- Rejection: Specimens with major discrepancies (Name mismatch) are rejected. Irreplaceable samples may be processed only after a signed Declaration of Correction
- Traceability: Barcodes are scanned at every step to track who handled the sample and when
Prepare, Label, & Store Reagents
- Preparation: Must follow SOPs using calibrated glassware and sterile technique (Laminar Flow Hood)
- Labeling (OSHA): Every reagent bottle must contain: Name, Concentration, Date Prepared, Expiration Date, Initials, and Hazard Warnings (GHS)
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Storage
- \(4^{\circ}\text{C}\): Media, Antibiotics, Mitogens
- \(-20^{\circ}\text{C}\): Serum (FBS), Trypsin, FISH probes
- Room Temp: Giemsa stain
- QC: New lots of reagents (especially Serum and Slides) are parallel-tested against old lots before use
Operate & Maintain Laboratory Equipment
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Incubators
- Temp: \(37.0 \pm 0.5^{\circ}\text{C}\)
- \(CO_2\): 5% (maintains pH). Verified weekly with Fyrite
- Humidity: 95–99% (prevents evaporation/osmolality shock)
- Biosafety Cabinet: Class II Type A2. Wipe with ethanol before/after use. Annual certification
- Microscopes: Daily cleaning of oil objectives. Weekly Kohler alignment
- Safety: Centrifuges must be balanced. Temperature logs (Freezers/Refrigerators) must be monitored daily
Monitor Laboratory Supplies & Chemicals
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Inventory
- Kanban/Tag System: Triggers re-orders when stock hits a minimum level
- FIFO: First-In, First-Out rotation prevents expiration
- Critical Reagents: Maintain “safety stock” of FBS and Media
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Chemical Safety
- SDS: Must be available for all chemicals
- Tracking: Expiration dates are tracked from the “Open Date,” not just the manufacturer date
- Waste: Segregate Biohazard (Red), Chemical (Fixative), and Sharps