Not all laboratories are created equal. A small university research facility conducting occasional Gram staining procedures has vastly different needs than a busy NHS diagnostic laboratory processing hundreds of specimens daily.
Yet for decades, many suppliers have taken a one-size-fits-all approach to laboratory reagent packaging, forcing labs to choose between inconveniently small bottles that run out too quickly or bulk containers that deteriorate before they’re used up.
At Pro-Lab Diagnostics, we’ve been manufacturing microbiology stains in-house at our UK facility since 1989. Over those 35 or more years, we’ve learned that smart packaging isn’t just about convenience; it’s about helping laboratories work more efficiently, supporting laboratory sustainability practices, saving money, and maintaining the quality of their diagnostic work.
Browse our products at Pro-Lab Diagnostics to learn more about how we can support your lab’s success or contact us today to join our extensive network of labs across the globe.
UK laboratory sustainability initiatives, including the Laboratory Efficiency Assessment Framework (LEAF) and university Green Lab programmes, have demonstrated that reagent packaging plays a critical role in operational efficiency and waste reduction. Universities across the UK – from Oxford to Edinburgh to Nottingham – have documented that purchasing chemicals in inappropriately sized containers leads to multiple problems:
Increased waste from expired reagents
According to the University of Edinburgh’s sustainable laboratory guidance, when labs purchase bulk containers without matching them to actual consumption patterns, significant portions deteriorate or expire before use. UK universities have documented that checking chemical inventories before ordering and matching bottle sizes to usage prevents materials being discarded when they reach expiry dates.
Higher disposal costs
As noted by UK universities implementing sustainable laboratory practices, chemical and solvent waste disposal is expensive and time-consuming. The University of Essex’s waste disposal guidance highlights that solid chemical waste, including expired reagents, requires specialist handling and is costly to dispose of properly. Matching bottle sizes to actual needs prevents this double financial burden of unused purchases and disposal fees.
Safety and handling risks
UK laboratories working under COSHH (Control of Substances Hazardous to Health) regulations recognise that smaller containers substantially reduce handling risks. The UK Standards for Microbiology Investigations specifically notes the importance of following local COSHH assessments when performing staining procedures. Smaller bottles mean less exposure potential during transfers, fewer opportunities for spills, and simplified safe working practices.
Storage space inefficiency
In UK laboratories where space is often at a premium, bulk containers take up valuable shelf space. The Royal Society of Chemistry’s sustainable laboratories guidance emphasises that appropriate sizing helps optimise limited storage capacity whilst maintaining proper storage conditions for reagent stability
The Gram stain remains the most commonly used staining technique in microbiology, having remained essentially unchanged since Hans Christian Gram developed it in 1884. Despite its longevity, the quality of Gram staining – and all microbiological staining procedures – depends critically on reagent freshness and stability.
Once opened, staining reagents begin to degrade through several mechanisms: evaporation of volatile components, oxidation, microbial contamination, and photodegradation for light-sensitive stains. The rate of degradation accelerates with each opening of the container and increases with the surface area of exposed reagent.
This is where bottle sizing becomes critical. A laboratory performing 20 Gram stains per week will work through a 250ml bottle in a reasonable time-frame, maintaining reagent quality throughout. That same lab purchasing a 2-litre container will take months to use it up – during which time the stain quality will gradually decline, potentially affecting diagnostic accuracy.
Sustainability research from UK institutions has demonstrated the significant impact of proper inventory management. A case study at the University of Edinburgh showed that laboratories can reduce chemical waste substantially by checking with colleagues before ordering and ensuring appropriate container sizes are selected. The key is matching container size to actual consumption patterns – a principle central to sustainable laboratory practice.
Low-volume research laboratories
Small research facilities, university teaching laboratories, and specialised diagnostic units often perform staining procedures on an as-needed basis. These laboratories benefit enormously from smaller bottle sizes – typically 100ml to 250ml bottles, or even precision dropper bottles for specialty stains used infrequently. The advantages are clear: reagents remain fresh throughout their use, storage space is minimal, and there’s virtually no waste from expired chemicals.
Medium-throughput clinical laboratories
Regional hospital laboratories and mid-sized NHS diagnostic facilities typically process a steady volume of specimens. These laboratories often find that 500ml to 1-litre bottles strike the optimal balance – large enough to avoid constant reordering, but small enough to be used up while reagents are still fresh. NHS laboratories have increasingly implemented inventory management systems that track reagent usage patterns, helping optimise ordering and reduce waste whilst maintaining the quality of diagnostic testing.
High-volume diagnostic centres
Large hospital networks, public health laboratories, and high-throughput diagnostic centres may process thousands of specimens weekly. For these facilities, our larger containers (up to 2 litres) make perfect sense. The stains are consumed quickly enough that freshness isn’t compromised, the per-unit cost is minimised, and the reduction in packaging waste aligns with environmental sustainability goals.
Since opening our UK manufacturing facility specifically for staining solutions in 1995, Pro-Lab Diagnostics has maintained an unwavering commitment to quality regardless of bottle size. Every batch of Pro-Stains™ – whether destined for a small dropper bottle or a bulk container – goes through the same rigorous manufacturing and quality control processes.
Unlike companies that outsource production or simply repackage products from other manufacturers, we produce our stains in our own purpose-designed laboratories. This gives us complete control over every aspect of production – from raw material selection to final filtering and quality checks. It also means we can respond quickly to customer needs and maintain consistency across all bottle sizes.
We start with the finest raw materials available and employ strict filtering techniques before any stain is released. This ensures excellent performance characteristics and consistent results, whether you’re using a 30ml dropper bottle or a 2-litre container. Each batch meets all current regulatory requirements and carries CE labelling.
Our Pro-Stains™ range includes ready-to-use solutions, concentrated formulations (typically 10x), and convenient staining kits. We offer Gram stains, acid-fast stains for mycobacteria, Cryptosporidium stains, and a comprehensive selection of specialty stains. Each type is available in multiple sizes, allowing laboratories to choose the format and volume that best suits their workflow.
Over our decades of working with laboratories across the UK and internationally, we’ve heard consistent feedback about the practical benefits of having bottle size options:
“We used to throw away half of every bulk container because it would expire before we could use it all. Now we order the 500ml size and use every drop.”
University Research Laboratory
“The dropper bottles are perfect for our specialist fungal stains that we only use a few times a month. There’s no waste, and they stay fresh.”
Regional Diagnostic Centre
“For our high-volume TB screening, the 2-litre containers make financial sense and we go through them quickly enough that quality is never an issue.”
Public Health Laboratory
When selecting stain bottle sizes for your laboratory, consider these factors:
Current usage patterns
Track how many staining procedures you perform weekly or monthly. This data will guide your bottle size selection and help prevent over-ordering.
Shelf life after opening
Consider how long a stain remains stable once opened. Some stains have shorter shelf lives and benefit from smaller bottles even in busy laboratories.
Storage capacity
Evaluate your available storage space. Bulk containers require more room, and proper storage conditions (temperature, light protection) are essential for maintaining quality.
Cost per unit versus waste
While larger bottles typically offer better per-millilitre pricing, any savings disappear if you’re disposing of expired reagent. Calculate the true cost including potential waste.
Seasonal variations
Some laboratories experience fluctuating workloads. Having access to multiple bottle sizes allows you to adjust orders based on anticipated demand.
Environmental considerations
Sustainability in UK laboratory operations has become increasingly important, with initiatives like LEAF (Laboratory Efficiency Assessment Framework) at Oxford and Green Impact schemes across universities highlighting the environmental impact of laboratory work. Laboratories are estimated to use 3-10 times more energy per square metre than typical offices, with corresponding impacts from waste generation.
When laboratories purchase appropriately sized bottles, they reduce chemical waste – a far more significant environmental impact than packaging materials alone. As the Royal Society of Chemistry’s sustainable laboratories guidance emphasises, using every drop of reagent before it expires means fewer chemicals entering the waste stream and lower disposal costs. UK universities have documented that preventing waste at source is always preferable to managing waste after it’s created.
Additionally, ordering the right size reduces the frequency of deliveries (compared to constantly reordering small bottles) while avoiding the waste of bulk ordering. It’s an approach that balances practical efficiency with environmental responsibility.
Laboratory staining may be a technique that dates back to the 1880s, but the way we package and deliver these essential reagents continues to evolve. At Pro-Lab Diagnostics, we understand that true customer service means offering options – not just pushing the largest container because it has the best profit margin.
Whether you need precision dropper bottles for occasional use, mid-size containers for steady workflows, or bulk packaging for high-volume operations, the principle remains the same: the right size at the right time means fresher reagents, less waste, better value, and more reliable diagnostic results.
We’ve been manufacturing stains in-house since 1989, and we’ll continue doing it the same way; with attention to quality, flexibility for our customers, and respect for the crucial work that laboratories do every day.
An extensive range of ready to use and concentrated microbiological staining solutions in a selection of convenient, economical sizes.
All stains are manufactured in our own purpose designed laboratories to the highest standards, in accordance with all current regulatory requirements and CE labelled. Using the finest raw materials, and adopting strict quality control and filtering techniques prior to release, all stains offer excellent performance characteristics. Also available are a range of convenient staining kits for Gram, TB and Cryptosporidium staining.
In addition to the standard range of products available routinely, Pro-Lab Diagnostics also offer a custom delivery and preparation service. To enquire or order, please contact our sales coordination desk (T: 0151 252 1613 / E: uksupport@pro-lab.co.uk)
