Failure Case Library

Real lab failures, root causes, and fixes — curated and bilingually annotated by our team.

All Techniques (6) Nucleic Acid Quantification (9) Lipid Transfection (8) End-point PCR Primers (9) Cell Culture (Contamination) (7) PCR (Sigma Guide) (12) Flow Cytometry (Controls) (8) PCR / qPCR Plastics (9) PCR (Invitrogen Guide) (8) Cell Culture (Precipitates) (6) Cell Culture (Cell Death) (8) ELISA (Sigma Guide) (6) PCR / RT-PCR Amplification Problems (5) Flow Cytometry (Paraformaldehyde Fixation) (14) Flow Cytometry (Sample Considerations) (14) ELISA (R&D Guide) (10) Western Blot Immunodetection (19) Flow Cytometry (CST Guide) (8) Immunohistochemistry (CST Guide) (14) Immunoprecipitation (CST Guide) (14) ChIP (CST Guide) (8) ELISA Development (9) Western Blot (Sigma Protocol) (8) IP-Western Blot (6) Western Blot (CST Guide) (8) Flow Cytometry (Fixation Buffers) (7) Flow Cytometry (Isotype Controls) (7) Flow Cytometry (Fixation & Permeabilization) (9) Flow Cytometry (Fc Blocking) (7) Flow Cytometry (Compensation) (7) Flow Cytometry (Autofluorescence) (7) Flow Cytometry (Troubleshooting) (8) Tissue Imaging (Autofluorescence) (9) ELISPOT (8) Immunoprecipitation (Protein Obstruction) (1) Immunoprecipitation (No Protein Detected) (5) Immunoprecipitation (High Background) (8) Immunoprecipitation (High Antibody Elution) (1) Immunohistochemistry (No Staining) (9) Immunohistochemistry (High Background) (9) ChIP (PCR Amplification Problems) (4) ChIP (Low Signal) (8) ChIP (Low Resolution with High Background) (6) ChIP (High Background) (1) Western Blot (Blue Background) (1) Western Blot (Unusual Gel Band Appearance) (3) Western Blot (Unexpected Multiple Bands) (7) Western Blot (Misshapen / Uneven Bands) (5) Western Blot (Bands at Wrong MW) (5) Western Blot (Detection Problems) (7) Western Blot (Weak / No Signal) (6) ELISA (Standard Curve Fit Problems) (6) ELISA (Inconsistent Results / High CV) (6) ELISA (High Background) (8) ELISA (Signal Problems) (11) ELISA (Competitive) (18) Cell-free DNA Extraction (8) Bacterial rRNA Depletion (4) RNA Depletion for RNA-seq (7) LAMP (Loop-mediated Isothermal Amplification) (7) HMW DNA Extraction (Monarch) (7) NGS Library Preparation (NEBNext Ultra II) (7) RNA Cleanup (4) DNA Cleanup & Plasmid Purification (7) PCR (Polymerase Chain Reaction) (26) Restriction Enzyme Digest (13) Western Blot (9) Immunohistochemistry (IHC) (6) Colony Formation Assay (10) Transwell Migration / Invasion Assay (5) qPCR (RT-qPCR) (5) Transfection (8) Plasmid Construction (1) Sanger Sequencing (2) Plasmid Mini-prep (1) Plasmid Construction (Double Digest) (1) Protein Extraction (4) Transfection (Co-transfection) (1) Transfection (siRNA Knockdown) (1) CCK-8 Cell Viability Assay (5) Wound Healing Assay (5)
Cell Culture (Precipitates) moderate

Temperature-Induced Protein Precipitation in Culture Media

Turbidity or visible precipitates appear in cell culture media after temperature changes. High-molecular weight plasma proteins fall out of solution, creating visible cloudiness that may interfere with microscopy and imaging assays.

💡 4 causes ✓ 4 fixes
Cell Culture (Precipitates) moderate

Evaporation-Induced Salt Crystallization on Culture Surfaces

Crystal precipitates form readily on culture flask and plate surfaces. Media concentration increases due to water loss, causing salt components to exceed solubility limits and crystallize on plastic surfaces.

💡 4 causes ✓ 4 fixes
Cell Culture (Precipitates) severe

Trace Metal Precipitation in Serum-Free Formulations

Copper, iron, and zinc supplements precipitate out of serum-free media, creating a toxic environment for cells. Metal precipitates appear as dark particles and can compromise cell viability due to altered bioavailability and oxidative stress.

💡 4 causes ✓ 4 fixes
Cell Culture (Precipitates) moderate

Salt Precipitation from Concentrated Media Stocks

Concentrated media stocks (10x or higher) show salt precipitates particularly after refrigeration. Precipitates may redissolve upon warming but can lead to inaccurate final concentrations if not properly managed.

💡 4 causes ✓ 4 fixes
Cell Culture (Precipitates) severe

Calcium Salt Crystal Formation in Serum-Free Media

Insoluble calcium sulfate (CaSO4) crystals form in serum-free media preparations. Crystalline precipitates appear as visible artifacts under microscopy and may alter media composition by removing essential calcium.

💡 4 causes ✓ 4 fixes
Cell Culture (Precipitates) severe

Nutrient Loss via Chelation by Precipitates

Cell health deteriorates due to precipitate-mediated removal of essential nutrients. Precipitates chelate metal ions, vitamins, and other media components, effectively reducing their bioavailability and altering intended media composition.

💡 4 causes ✓ 4 fixes