Smarter Serial Dilutions.
Less Work. Lower Costs. Less Waste

Serial dilution is a routine but labour-intensive step in microbiological testing. Traditional tube-based workflows require repeated preparation, tube handling, mixing and reprocessing. Pre-filled disposable containers can simplify preparation, but often increase consumable costs, storage requirements and plastic waste.

The Inlabtec Serial Dilution System offers a different approach: sterile, low-material Serial Dilution Bags combined with automated diluent dispensing and integrated mixing — for fast, standardised serial dilutions without changing established laboratory procedures.

At a Glance

Less Work: No tube preparation, washing, autoclaving or separate vortexing before use.

Lower Costs: Up to 90% lower consumable costs compared with pre-filled disposable dilution containers.

Less Waste: Only 250 mg polyethylene per bag and minimal storage space.

Consistent Dilutions: Automated dispensing and integrated mixing support reproducible dilution steps.

Right System: UA for up to around 50 samples per day; UC from around 50 samples per day.

The Challenge in Routine Serial Dilution in Microbiology

Decimal serial dilution is standard practice in microbiological testing. In conventional workflows, laboratories usually prepare sterile tubes or containers with 9 ml diluent and add 1 ml of sample to create each dilution step.

Although this method is well established, it involves many repetitive manual steps: preparing and filling dilution tubes, sterilising prepared tubes, organising tubes before use, pipetting from one dilution step to the next, vortexing or mixing each dilution step, and cleaning, washing and reprocessing reusable glassware.

These steps require trained personnel, take time and introduce operator-dependent variability. As sample numbers increase, the workload becomes more significant and can limit daily laboratory efficiency.

The Limitation of Pre-Filled Disposable Containers

Pre-filled disposable dilution containers can reduce preparation work, but they also introduce other disadvantages. They require considerable storage space, generate more packaging and plastic waste, and often result in high consumable costs per dilution.

For laboratories performing serial dilutions regularly, this leads to an important practical question:

The Inlabtec answer is based on a simple principle:

So much single-use convenience as necessary.
So little material as possible

The Inlabtec approach differs by combining sterile, low-material Serial Dilution Bags with automated dispensing and integrated mixing.

Single-use materials offer important advantages in microbiological laboratories: they are sterile, ready to use and reduce preparation, cleaning and sterilisation work. However, serial dilution usually requires only a simple, short-term container for sterile filling, reliable mixing and safe sample transfer.

For this purpose, rigid plastic tubes or pre-filled disposable containers often use more material, volume and packaging than necessary. In most routine workflows, dilution steps are processed immediately and are not intended for long-term storage.

This is why we developed the Inlabtec Serial Dilution System around the Serial Dilution Bag. Each bag uses only about 250 mg of polyethylene, while the system provides the functionality required for a standardised serial dilution workflow: sterile filling, automated diluent dispensing and integrated mixing.

Together, the bag and device reduce manual handling, material use, storage volume and waste.

The Inlabtec Solution

The Inlabtec Serial Dilution System was developed to simplify routine serial dilution while remaining compatible with established microbiological methods.

Instead of prepared dilution tubes, the system uses sterile Serial Dilution Bags. The user pipettes the sample into the filled bag, and the Serial Diluter performs the key process steps: diluent dispensing and mixing.

This reduces manual preparation work, eliminates tube washing, autoclaving and separate vortexing, and supports a standardised dilution process throughout the dilution series.

How the System Works

The Inlabtec Serial Dilution System combines three elements to create a fast, clean and standardised workflow for decimal serial dilutions.

1. Sterile Serial Dilution Bags

• The bags are ready to use, compact to store and made from only 250 mg of polyethylene per bag.

2. Automated Diluent Dispensing

The Serial Diluter dispenses the required volume of diluent into the next dilution bag.

3. Integrated Mixing

The sample and diluent are homogenised directly in the bag, eliminating the need for separate vortexing.

These three elements lead to practical benefits in daily laboratory work:

Compare: Traditional Tube Workflow vs. Inlabtec Serial Dilution System

The following workflow comparison shows how ready-to-use bags, automated dispensing and integrated mixing reduce key manual steps compared with conventional tube-based serial dilution.

Working Step	Traditional Tube Workflow	Inlabtec Serial Dilution System
Preparation before dilution	Prepare, fill and sterilise dilution tubes, or arrange pre-filled tubes or containers at the workplace.	Start the Serial Diluter, connect diluent, insert bags.
Sample transfer	Open the tube, pipette 1 ml sample into 9 ml diluent, then close the tube again.	Pipette sample into the filled bag.
Mixing	Mix the tube manually, usually by vortexing. Mixing quality depends on handling technique and mixing time.	Automatic mixing in the bag.
Next dilution step	Open the tube again, pipette the diluted sample into the next tube, close the tube and repeat the process.	Pipette diluted sample into the next filled bag.
Tube or bag handling	Used and unused tubes must be clearly separated to avoid mix-ups. Caps require additional handling.	Bags remain arranged in the Bagholder.
After use	Reusable tubes must be collected, washed, sterilised and stored for the next use. Disposable containers must be discarded.	Dispose of bags according to lab procedures.
Main workflow impact	Established method, but preparation and handling effort increase with sample numbers.	Less preparation. Fewer handling steps. Standardised dilution.

Serial Dilution Bags: A Practical Alternative to Conventional Dilution Tubes

Inlabtec Serial Dilution Bags are sterile, ready-to-use consumables developed specifically for Inlabtec Serial Diluters. Each bag is made from only 250 mg of high-quality polyethylene, keeping material use per dilution very low.

The compact bag format eliminates the preparation and reprocessing of dilution tubes, while reducing manual handling and storage requirements. The bags are compatible with standard microbiological methods and support efficient, standardised routine dilution workflows.

Reusable glass tubes remain a sensible option in laboratories with low sample numbers. However, as the number of samples processed each day increases, preparation, filling, cleaning and sterilisation become increasingly time-consuming. In the Inlabtec Serial Dilution System, Serial Dilution Bags replace the prepared dilution tube and eliminate these tube-related workflow steps.

For laboratories that regularly perform serial dilutions, Serial Dilution Bags in combination with the Inlabtec Serial Diluter offer a practical alternative. As daily sample numbers increase, the benefits of reduced preparation work, simplified handling and compact storage become increasingly relevant.

From Bag to Automated Dilution System

Serial Dilution Bags are a central component of the Inlabtec Serial Dilution System. They replace the prepared dilution tube and are specifically developed for automated diluent dispensing and integrated mixing with Inlabtec Serial Diluters.

The result is a standardised, ISO-compatible 1 ml + 9 ml dilution workflow with less preparation, less manual handling and no tube reprocessing. The system is used in ISO/IEC 17025 accredited laboratories of leading laboratory service providers for routine microbiological testing.

Depending on sample throughput and automation requirements, laboratories can choose between the semi-automatic Serial Diluter UA for up to around 50 samples per day and the fully automated Serial Diluter UC from around 50 samples per day.

Serial Diluter UA – Cost-Effective Automation for Routine Labs

The Serial Diluter UA is the semi-automatic solution for laboratories that want to simplify serial dilution with a robust and cost-effective system.

Mixing and filling of the next dilution bag are triggered by moving the dosing lever to the right. After a short familiarisation period, users can prepare dilution series quickly and consistently without tube handling, vortexing, washing or autoclaving.

The UA is ideal for laboratories processing up to around 50 samples per day.

Serial Diluter UC – Maximum Automation for Higher Throughput

The Serial Diluter UC is the fully automated solution for laboratories with higher daily sample numbers and a stronger need for guided workflows.

Illuminated bag openings guide the user through sample addition and sample retrieval. Sensors detect key workflow steps and control the automated mixing and dispensing sequence. This reduces manual handling and supports a consistent dilution process.

The UC is recommended for laboratories processing from around 50 samples per day.

Calculate Your Savings

For equipment investments, laboratories often want to understand the expected cost savings and payback period. The savings calculator provides an initial estimate based on typical workflow assumptions.

For a precise profitability analysis, please contact Inlabtec or your local distribution partner. Equipment prices, logistics costs and prices for Serial Dilution Bags may vary depending on country, distributor and order quantity. The annual purchase volume of Serial Dilution Bags is particularly relevant for pricing.

Note: The calculation is shown consistently in US dollars (USD).

Less Work. Lower Costs. Less Waste

The Inlabtec Serial Dilution System was developed for laboratories that want to simplify routine serial dilution without adding unnecessary complexity.

By combining sterile, low-material Serial Dilution Bags with automated diluent dispensing and integrated mixing, the system reduces routine workload, supports consistent dilution steps and helps laboratories reduce material use, storage requirements and routine handling time.

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