- Made from Borosilicate 3.3 glass.
- With Screw Thread and Teflon Liner.
- Leakproof.
- Comes with PP Screw Cap
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CAT NO Capacity ml. O.D. x Length(mm) 5 16×50 10 25×50 15 25×57 30 25×95 40 25×145
OVERVIEW :
GWSI flat bottom amber culture media tubes provide essential light protection for photosensitive media and cultures while offering stable, upright storage. Made from amber borosilicate 3.3 glass, they block harmful UV and visible light that degrades vitamins, antibiotics, and other light-sensitive media components. The flat bottom ensures stable standing in racks and incubators, while the amber tint maintains high thermal shock resistance and chemical inertness for demanding sterilization and culture workflows.
HISTORY :
Amber glass culture tubes emerged as researchers discovered that standard clear glass allowed light penetration that degraded critical media components over time. Vitamins, certain antibiotics, fluorescent compounds, and photosensitive nutrients broke down when exposed to laboratory lighting or sunlight, compromising experimental results and media shelf life. The amber tint solved this by filtering out UV and high-energy visible light while still allowing visual inspection of culture growth. Flat bottom designs were adopted for stability during media preparation, storage, and observation of sediment formation.
APPLICATIONS :
– Pharmaceutical microbiology labs— storing and culturing with light-sensitive antibiotics, vitamins, and fluorescent markers
– Biotech facilities — maintaining cell cultures requiring protected media components and photosensitive growth factors
– Clinical laboratories — preparing and storing light-sensitive diagnostic media and reagents
– University teaching labs — demonstrating effects of light on media stability and proper storage techniques for sensitive compounds
– College research groups — working with fluorescent proteins, photosynthetic organisms, and light-degradable supplements
– Industrial QC labs — stability testing of light-sensitive media formulations and quality control of photosensitive reagents
– Environmental microbiology — cultivating phototrophic microorganisms and protecting light-sensitive environmental samples
MANUFACTURING PROCESS :
GWSI manufactures flat bottom amber culture media tubes by melting amber borosilicate 3.3 glass at 1,650°C and forming the cylindrical body and flat bottom through precision automated molding or skilled hand-blowing. The amber coloration is achieved through controlled addition of iron and sulfur compounds during glass melting, creating uniform light-blocking properties throughout the glass matrix. The open top is fire-polished for smooth closure acceptance, and the entire tube undergoes controlled annealing to eliminate internal stress and ensure dimensional stability.
TESTING PROCESS :
Manual inspection verifies wall thickness uniformity, flat bottom stability, rim smoothness, and amber tint consistency on every tube. Automated polarization stress testing then scans the glass for residual strain that could cause failure during autoclaving or handling. Sample tubes from each batch are autoclave-tested at 121°C to verify thermal stability, and light transmission testing confirms adequate UV and visible light blocking performance for photosensitive applications.
PRINTING PROCESS:
Identification areas and optional volume markings are screened onto the amber tube surface using ceramic glass inks formulated for colored borosilicate compatibility. The tubes enter high-temperature kilns where ceramic glass fusing permanently bonds the ink into the glass matrix. This creates durable, legible markings that remain visible on the amber background and resist media stains, solvents, and repeated autoclaving.
PACKAGING PROCESS:
Final sorting removes any tubes with wall defects, rim imperfections, flat bottom irregularities, or inconsistent amber coloration. Approved tubes are individually wrapped or nested in compartmentalized trays to prevent contact damage during shipping. They’re packed in heavy-duty double-wall corrugated boxes with shock-absorbing dividers, suitable for domestic distribution or international export to research and clinical facilities.
MAINTENANCE & SAFETY:
– Clean immediately after use by discarding culture material and soaking in appropriate disinfectant before washing with detergents
– Autoclave at 121°C / 15 psi for sterilization; amber glass maintains UV-blocking properties through repeated autoclaving cycles
– Inspect before each use for cracks, chips, or stress marks that could compromise sterility or cause breakage
– Store upright in racks to take advantage of flat bottom stability and protect contents from light exposure
– Handle with care when hot after autoclaving; use heat-resistant gloves and allow tubes to cool before adding light-sensitive media
– Monitor amber tint over time; significant fading or discoloration may indicate reduced light protection and warrant replacement
Manufactured by GWSI Glass Lab — Ambala, Haryana, India (The Science City)