|Clever serial dilution process provides better performance at lower costs|
|May 31, 2018|
|Food Safety Magazine, the leading content provider of science-based solutions for food safety and quality assurance professionals published exclusively a Signature Series article on how testing by an accredited testing laboratory confirmed that automated sample dilution provided by the Serial Diluter increases reliability and accuracy of food testing compared to the traditional manual test tube method.
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|New Product: Serial Diluter TA12|
|March 16, 2018|
|iNLABTEC AG introduces the Serial Diluter TA12 developed in response to the demand from food culture and probiotic producers undertaking final quality control using the standard plate count method therefor needing up to twelve dilution steps per sample. With the new TA12 a twelve-step serial dilution is a breeze!
Demo Video TA12
|Filter plugs ensure contamination-free pipetting|
|November 7, 2017|
|iNLABTEC AG has introduced Universal Pipette Filter Plugs designed to provide a final barrier to protect the internal components of pipettes from contamination due to accidental splashes during pipetting, foaming samples or aerosolized vapours. more on this|
|Serial Dilution Bags Greatly Benefit Microbiological Food Testing|
|October 15, 2017|
|The short article discusses the benefits gained from use of application specific sterile plastic bags in microbiological food testing and compares the now standard protocol of using sample preparation bags for stomaching* with how the Inlabtec Serial Diluter makes it possible to now perform serial dilutions in dedicated serial dilution bags expanding the use of bags as a cost and resource saving alternative to test tubes or cups prefilled with diluent.
In stomaching a sample together with diluent is put into an inexpensive, sterile plastic bag which is vigorously pounded by paddles when placed inside the paddle blender. Using disposable sample preparation bags eliminates the considerable labour required to clean and sterilize reusable homogenizer cups, running costs are thus drastically reduced. Consequently, stomaching samples in bags quickly became the standard method of homogenizing samples and is now referenced by thousands of users.
In microbial testing, homogenized foods samples are used for viable cell counting where in most cases serial 10-fold dilutions are mandatory. Since the end of the 19th century, serial dilution protocols have dictated that 1 ml of homogenized sample is added to 9 ml diluent in a test tube, vigorously mixed and then aliquots taken for the inoculation of culture media. The used test tubes are afterwards washed, refilled with the diluent, capped and sterilized again. This time-consuming recycling of test tubes is nowadays often substituted by using prefilled test tubes or cups which considerably increase purchase, storage and waste disposal costs.
First introduced in 2014, the Inlabtec Serial Diluter pioneered the use of dedicated Serial Dilution Bags as an alternative to the traditional test tube techniques. Now proven in a rapidly growing number of food testing laboratories worldwide, users of the Serial Diluter have particularly appreciated that dilutions are considerably simplified and that the costs to undertake microbiological sample preparations greatly reduced. By using Serial Dilution Bags, the entire dilution process is now much less labour intensive and time-consuming, key contributions to a more comfortable and stress-free working environment. With a simple press of a button - users are now routinely able to obtain perfect dilutions leading to improved accuracy and precision of their testing results with minimal waste produced.
In the same way that the stomacher became the standard method for sample preparation already many labs are successfully working with the Serial Diluter. Many of these users are ISO 17025 accredited labs who are benefiting from substantial improvements in their testing productivity and the quality of their food testing results as well as to manage their responsibilities towards employees and the environment.
*: The stomaching principle was patented by A. N. Sharpe and A. K. Jackson in 1972
|Leading Food Hygiene Lab Reports on the Inlabtec Serial Diluter|
|September 8, 2017|
|Inlabtec has published a customer video report that describes the experiences of Swiss Quality Testing Services(SQTS) (Courtepin, Switzerland) in replacing traditional test tube based serial dilution with the Inlabtec Serial Diluter.
SQTS is a leading Swiss provider of quality laboratory services for food testing. Using state-of-the-art analytical methods, more than 80 experts offer comprehensive services for virtually all quality assurance issues from the conception phase to marketed products. SQTS examines the composition, authenticity and hygiene of food products and test samples for daily use - as well as testing goods for the home, garden and leisure segment.
At the beginning of 2015, after a period of evaluation, SQTS elected to replace using 9 ml test tubes for ISO 6887-1 serial dilution food hygiene testing with an Inlabtec Serial Diluter. Within a short period of time the Serial Diluter became an indispensable tool for sample preparation.
Today, staff at SQTS prepare food samples for microbial plate counts exclusively with three Inlabtec Serial Diluters. Lab staff on the video describe how they appreciate no longer having to prepare and clean serial dilution test tubes every day. They also comment on the ease of use, reliability and the automatic dilution of the samples, which reduces the handling steps compared to the test tube technique making the task much more pleasant.
The SQTS laboratory manager in the video commented that using the Inlabtec serial diluters has generated enormous savings in time giving him more flexibility in planning fluctuating sample workload and optimal use of staff.
To watch the video report from SQTS please visit youtube or www.inlabtec.com where under Demo Videos a version including Chinese subtitles is available.
|Inlabtec Serial Diluter Chosen by Leading Food Safety Testing Organization|
|July 10, 2017|
|The Inlabtec Serial Diluter has been successfully used by lab staff at SGS Fresenius since the beginning of 2015 eliminating the traditionally laborious task of preparing test tubes as well as vortexing during dilutions. To make sampling out of standard homogenizer bags (stomacher bags) easier, the laboratory team decided after a three-week intensive test phase to change to the recently introduced Inlabtec Serial Diluter SA for pipette straws.
SGS is the world's leading inspection, verification, testing and certification company and recognized as the global benchmark for quality and integrity. With more than 90,000 employees, SGS operates a network of more than 2000 offices and laboratories around the world. SGS INSTITUT FRESENIUS GmbH as part of the SGS Group Germany is one of the most important German providers of laboratory analytics for the safety and quality of food, beverages and consumer products with an excellent reputation among producers, consumers and trade.
The entire SGS laboratory team was quickly convinced by the improved sample handling and enhanced productivity when working with straw pipette tips. In addition, using the Inlabtec Serial Diluter to sample out of standard homogenizer bags has made the whole process even easier and faster.
Despite initial scepticism from some lab staff, the integration of the Inlabtec Serial Diluter into the existing workflow was quick and easy since no process changes or special training was required. SGS have reported considerable time savings using the Inlabtec Serial Diluter and cost savings related to eliminating the need to clean and then store dilution test tubes in a refrigerator. The Inlabtec system has provided reliable sterile operation as has been expected from the instrument’s design.
To watch a video report from SGS Fresenius describing their experiences with the Inlabtec Serial Diluter for straw pipette tips please visit youtube or download
|Proficiency Tests confirm improved Accuracy and Consistency|
|May 22, 2017|
|The results from interlaboratory (proficiency) tests by an ISO/IEC 17025 accredited and GMP compliant Swiss testing laboratory show a clear improvement in the accuracy and consistency of Total Viable Count determinations using the Inlabtec Serial Diluter.
Figure: Comparison of the z-score values of different technicians using test tubes and vortexer (lower axis) and/ or the Inlabtec Serial Diluter (upper axis) for serial dilutions for viable cell count determination.
Compared to the traditional test tube technique, the serial diluter automates sample dilution in a single step which integrates precise dispensing and homogeneous mixing. This leads to higher accuracy as well as to a higher consistency in test results between technicians as the automated dilution performed by the Serial Diluter minimizes the potential of human errors and individual differences in microbiological technique.
Using the Inlabtec Serial Diluter, all lab staff has been able to deliver microbiological results of the highest reliability and quality, regardless of professional experience and manual skills. In addition, the technicians benefit from a faster, simplified dilution process as well as eliminating time spent washing, filling, autoclaving or checking test tubes.
More information on request
|Serial Diluter SA for dilutions and sample handling using pipette straws|
|March 20, 2017|
|The Inlabtec Serial Dilution System automates the traditionally labour-intensive process of serial dilution. With the Serial Diluter SA it has become now possible to use pipette straws instead of 1 ml pipette tips.
|Added Functionality to Inlabtec Serial Diluter|
|March 8, 2017|
|A new software release makes is very easy and convenient to purge and empty the tubing set for the decommissioning of the Serial Diluter.
After pressing the OPEN VALVES key and by using the ASPIRATE key the remaining liquid in the aspiration tube and the pipette is pushed back into the bottle, container with flushing water, etc. Thus the tubing set is completely emptied before it is removed from the device. Therefore an uncontrolled leakage of liquid is not possible anymore.
See for demonstration: Inlabtec Serial Diluter Function Purge
In addition, we have changed the control of the internal air reservoir, which can be noticed by additional 1-2 seconds more time required by the instrument until it is ready for use after an automatic stop (air bubbles, bottle empty, etc.). This improvement adds additional precision as the pressure in the air reservoir is more closely controlled.
Further, the Serial Diluter will switch off automatically after 30 minutes, if this has been forgotten.
The new software AP170307 (MHX-file) can be downloaded from our website section resources. How to execute a software update can be found in the operating instructions or is demonstrated by a video available on our website section resources.
|Simplicity through Reduction with Inlabtec Serial Diluter|
|September 9, 2016|
|WESSLING AG, located in Lyss, Switzerland, is a leading analytical service provider in the fields of environment, food, feed, water, consumer goods and cosmetics. It is part of the international WESSLING group of companies with 1200 employees at more than 30 locations in Europe and China. The consistent, ongoing optimization of the processes and services ensures the lab group its leading market position and a continuous dynamic growth.
In order to use the existing resources within WESSLING AG even more productively, an Inlabtec Serial Diluter was purchased for the microbiological food and water testing. After a brief introduction and habituation phase, the laboratory team appreciates the simple fast precise and comfortable work.
Prior to the introduction of the Serial Diluter, the lab team had to clean, to fill, to cap and to sterilize test tubes before pipetting and vortexing 1 ml of sample in 9 ml of diluent for a 1:10 dilution. All the work is now reduced to pipetting only. All other unproductive work steps have been eliminated because the clever Inlabtec system uses sterile, highly pure disposable bags, thus eliminating the costly preparation of test tubes. The performance of serial dilutions is now a fast, standardized process, which eliminates errors and inaccuracies by careless pipetting or insufficient vortexing. The reproducibility and the quality of the testing results have been further improved. Person-dependent differences for the determination of plate counts have been reduced to a minimum.
Serial dilutions by using the Inlabtec Serial Diluter have now become simple and cost-effective for Wessling AG. In doing so, the employees and the environment were relieved, the accuracy and reliability of the analytical results increased once again and thus the risk for inaccurate findings further reduced.
More information on request
|Cleaned test tubes not always clean enough?!|
|June 7, 2016|
|Comparative total viable counts (TVC) after performing serial dilutions using test tubes versus the Inlabtec Serial Diluter have identified growth-inhibiting residues in the test tubes used for dilution preparation. Due to the results obtained the test laboratory involved now uses the Inlabtec Diluter routinely to ensure the reliability of their food testing services.
A food microbiology laboratory prepared plate counts of different food samples in parallel using serial dilutions with self-prepared test tubes and with the Inlabtec Serial Diluter. An unexpected difference between the two dilution techniques for TVC) of -0.628 log CFU/ g was found (CFU: colony forming unit). Dilutions with the Serial Diluter systematically detected nearly five times more viable counts in the studied food samples compared with test tube dilutions. For the Enterobacteriaceae enumerated in parallel however, no difference was found as the average difference detected was only 0.017 log CFU/ g and therefore clearly within the usual range of uncertainty of ± 0.5 log CFU/ g for CFUs in food samples.
User errors with the Serial Diluter could be excluded. The diluent was the same for both techniques and the volumes used within the accepted tolerance.
A set of pre-filled test tubes (Oxoid TV5013D) were purchased for further comparisons. When comparing colony counts after serial dilutions with Inlabtec and purchased dilution tubes from Oxoid no difference was detected for TVC and for the number of Enterobacteriaceae for the food samples analyzed. The average difference between the two dilution techniques was within the usual uncertainty range of ± 0.5 log CFU/ g: for TVC -0.088 log CFU/ g and Enterobacteriaceae -0.054 log CFU/ g and would be considered statistically the same.
Due to the results obtained the presumed presence of growth inhibitory contaminants in self-prepared test tubes could be confirmed. In addition, different types of bacteria appeared to show different susceptibility to the possible contaminants.
The results confirm the reservations many laboratories have regarding multi-use test tubes and pipettes etc. Incomplete cleaning of glassware can be due to various factors such as unnoticed washer malfunction, incorrect washer loading, wrong program selection or detergent dosage, which can lead to the presence of growth inhibitory substances such as detergent residues and secondary metabolites etc. These can never be completely excluded and are a possible source of risk for reliable analytical results. Therefore ISO7218: 2007-11 describes the regular inspection of cleaned glassware for the absence of inhibitory substances and the US Environmental Protection Agency (US EPA) has a mandatory standard procedure defining how cleaned glassware has to be tested regularly for the presence of growth inhibitors so that the quality of water testing is guaranteed.
When using Serial Dilution Bags with the Inlabtec Serial Diluter inhibiting substances are completely excluded and therefore the reliability of laboratory test results can be guaranteed. The Serial Dilution Bags, made of high-purity PE foil, are manufactured and packed under cleanroom conditions, before being sterilized using radiation. The bags are guaranteed to be free of any inhibitors and therefore allow the reliable, reproducible detection of the whole microbial population in a sample including residue susceptible organisms.
The original laboratory that conducted these tests has now been using the Inlabtec Serial Diluter for over two years and is not planning to return to re-usable test-tubes for their serial dilutions emphasizing their commitment to the highest possible quality and reliability of services offered to their customers.
|Handle Homogenizer Bags Just Like Bottles with Inlabtec Bagboard|
|April 25, 2016|
|Unlike bottles, homogenizer or stomacher bags lack a rigid side making them unstable and therefore they need to be supported. Taking a homogenized sample out of a wobbly bag is a relatively complex task and can pose a contamination risk for the user and the environment. Furthermore, storage of the samples in a fridge or enrichments in an incubator takes up a lot of space and it can be difficult to keep the bags in a clearly organized order.
The new Inlabtec Bagboard gives an unstable homogenizer bag a defined rigid structure allowing the bags to be handled just like bottles. Working with homogenized samples in bags becomes as easy and convenient as bottles!
The durable Bagboard is reusable and offers benefits like:
- Bags can be easily handled, transported and stored, organized into the minimum space possible whilst keeping samples in order, safe and secure
- An integrated clamp makes sealing of the bags easy and convenient
- Efficient resuspension of the bag contents can be achieved by just repeatedly squeezing the Bagboard
- Sampling with standard pipettes is fast and convenient with reduced risk of contaminating user or equipment
The simply clever Inlabtec Bagboard improves the laboratory workflow after sample homogenization and accelerates follow-up processes like serial dilutions or plating. How it works may be viewed in a one minute video at www.youtube.com
For more information please visit www.inlabtec.com (direct link Bagboard)
For a free sample of a Bagboard contact the Inlabtec distributor in your country or contact Inlabtec AG in Switzerland.
|The Inlabtec Serial Diluter: A Success Story!|
|November 12, 2015|
|Wander AG in Neuenegg near Berne, Switzerland has been developing and producing quality food for 150 years and is famous for the milk flavouring product Ovaltine (Ovomaltine), which is one of the 20 most popular Swiss brands and successfully marketed in more than 100 countries (www.wander.ch). The ISO 9001: 2008 / 14001: 2004 and BRC certified company continuously strives for the very highest quality and its very competent quality control organization is responsible for the complete monitoring of all raw materials, processes and end products.
In order to create additional capacity to work through the growing numbers of samples for hygiene monitoring, the microbiology laboratory has purchased an Inlabtec Serial Diluter. This innovative system for performing serial dilutions for plate counts, quickly convinced the laboratory of it’s value due to time savings, the excellent precision and reproducibility and with its ease of use.
Every one of the team agreed: “The Inlabtec Serial Diluter is a great addition to the lab! Preparation of diluent can now be very quickly done in bottles since no test tubes for dilutions need to be prepared anymore. By using the Inlabtec Homogenizer Bags in combination with the Inlabtec Rack it is possible to quickly and cleanly take a sample of the primary dilution, using a standard 1 ml pipette. The setting up and the connection of the diluent solution is also very simple. And once set up, it can be used for up to six weeks without change because the Serial Diluter never comes directly into contact with samples due to the unidirectional dispensing of the sterile diluent and the sterility of the system is reliably maintained by sterile filters.“
The Inlabtec Serial Dilution system has impressed the laboratory team of Wander AG with its simplicity, reliability and easy operation. ”All in all a great thing, I wouldn’t want to give it away now!“ said Renate Perler, Laboratory Technician, Wander AG.
More information on request
|Comprehensive guide includes Inlabtec Serial Diluter|
|September 8, 2015|
|A test method guide available on rapidmicrobiology.com explains the Inlabtec Serial Diluter in the context of laboratory automation.
rapidmicrobiology.com provides an online information source for microbiology professionals around the world, with information on the latest products for clinical, pharmaceutical, food and water microbiology labs.
The Test Methods section on rapidmicrobiology.com includes the test method guide to “Automating the Food Microbiology Lab” discussing the great potential savings in microbiological analyses if automated.
The guide covers the whole process of traditional microbiological quality testing and shows how the Inlabtec Serial Diluter can improve efficiency of the lab and at the same time relieve the staff from very labor intensive and long term routine work.
|Verification of the Inlabtec Serial Diluter made easy|
|August 21, 2015|
|The Serial Diluter automates and improves the quality of serial dilutions for accurate plate counts. Test tubes are replaced by inexpensive, sterile disposable bags, thus eliminating the costly process of washing, filling and autoclaving test tubes for serial dilutions.
According to ISO/IEC 17025: 2005, general requirements for the competence of testing and calibration laboratories, accredited laboratories must confirm by verification that they are able to operate the applied standard methods adequately and that the specified accuracy and precision requirements are met.
Modifications of standard methods are verified by comparison with the respective methods. Serial dilutions made by the Inlabtec technique correspond to a modification of the standard method for the preparation of decimal dilutions ISO 6887-1: 1999-02.
For the rapid and smooth introduction of the Serial Diluter into routine, Inlabtec AG provides a guide and Excel template that describe the execution and documentation of the verification process by a comparison with the dilution method used currently. The verification documents are available under section Resources
|Simplifying Sample Preparation Boosts Productivity of Food & Feed Testing
|May 21, 2015|
|iNLABTEC AG reports on how they have helped Landwirtschaftliche Kommunikations und Servicegesellschaft (LKS) mbH, an accredited certification body for the German feed, agro and food industry, improve microbiological analysis productivity by simplification and acceleration of routine processes.
LKS mbH (www.lks-mbh.com) is a respected organization in the German agricultural quality testing market. The company has, over recent years, seen a marked increase in samples for microbiological and metabolic analyses driving the need to improve productivity / increase sample handling capacity in their ISO / IEC 17025 certified feed analysis laboratory. During harvest periods the laboratory also required a way of analyzing in a timely manner the additional large numbers of samples.
Using an Inlabtec Serial Dilution System has allowed LKS mbH to create and release the needed analysis capacity by simplifying and speeding up established routine processes without increasing staff numbers or significant investment into complex automation with high maintenance and service costs.
Prior to implementing the Serial Diluter – LKS microbiological analyses were carried out on the basis of comparative measurements using the traditional test tube method. The lab was typically faced with analyzing a wide variety of food samples as well as feed samples such as silage, pellets and compound feed for bacteriological and mycological activity.
At the beginning of the introduction of the Inlabtec Serial Diluter, laboratory staff was reluctant to change their routine processes. The Serial Diluter however has very quickly become an indispensable tool to cope with the rising numbers of samples and the sample peaks during the harvest periods. Staff have particularly appreciated that the preparation and storage of serial dilution materials has been extremely simplified and the space requirement required to undertake the microbiological analyses greatly reduced. The entire dilution process is now much less labour intensive (no more laborious cleaning of test tubes) and time-consuming. All that is required now is a simple press of a button on the Inlabtec Serial Diluter to obtain perfect dilutions and improved accuracy and precision.
More information on request
|Inhomogeneous dilution poses a potential risk to food quality & safety|
|April 7, 2015|
|Precise and accurate serial dilutions are important when determining viable cell counts and therefore form the basis of correct food quality assessments. Measured viable cell counts below the actual contamination level pose a significant risk for consumers of the food tested and therefore constitute a challenge for food testing labs.
A new report is available, using UHT milk as the model food sample, that examines the influence of mixing time on the homogeneity of dilutions achieved using the test tube method. Experimental data is presented that demonstrates how using mixing times of less than 5 seconds can lead to a systematic underestimation of the number of viable cell counts. These errors can give rise to false qualification of food tested and thus represents a major risk to consumers as well as for the food testing lab. Investigators demonstrate that using an Inlabtec Serial Diluter - perfect serial dilutions on the same sample model can be achieved in less than 4 seconds.
See detailed method comparison
|Inlabtec Serial Diluter Outperforms Test Tube Protocol
|February 5, 2015|
|After decades of using the traditional test tube method for serial dilutions the Centre for Laboratory Medicine (www.zlm.ch) in St. Gallen, Switzerland changed a year ago to the Inlabtec Serial Diluter. In the period since installation, the Inlabtec system has demonstrated itself as a sound investment through its constant high accuracy, high level of automation and clear, simple and easy operation.
The Centre for Laboratory Medicine (ZLM) is a recognized competence centre for medical analytics and diagnostics, accredited to ISO / IEC 17025, and ISO 9001 certified. The department of veterinary diagnostics carries out food hygiene studies for various clients.
All food samples at ZLM (Inlabtec Sample Selection) are now automatically diluted and mixed with the Inlabtec Serial Diluter at the push of a button to provide perfect serial dilution every time. In all inter-laboratory tests in which the ZLM participated, and in all internal comparisons carried out with the old test tube method, the high quality and reliability of results from the Inlabtec Serial Diluter were confirmed. Over the last 12 months - microbial count results using the Inlabtec method have been of consistently high accuracy. Beneficially the Serial Diluter has also eliminated the operator dependent scattering of results that was previously experienced with the labour-intensive test tube method.
For the whole ZLM team, the Serial Diluter has proved a major asset. The setup of the instrument is both simple and quick. During the operating week, only the empty bottles have to be replenished with a new dilution medium. As well as eliminating the labour intensive task of preparing test tubes required by the old method, the new protocol of conducting dilutions in Serial Dilution Bags avoids operator errors. All these benefits have ensured that all members of the ZLM team, regardless of their professional experience, have generated consistently high quality microbial counts using the Inlabtec Serial Diluter as well as achieving significant time and cost savings.
More information on request
|Consumer Protection Agency chooses Inlabtec Serial Dilution Systems|
|November 28, 2014|
|The Aargau Consumer Protection Agency (www.ag.ch), Switzerland, decided after extensive method verification and several months of practical tests to equip their food control laboratory with three Inlabtec Serial Dilution Systems and to decommission their existing systems.
The Inlabtec systems were procured because of the increased productivity benefits they offered over Aargau’s existing serial dilution systems. In particular the lab manager and staff were impressed at the Inlabtec Serial Diluters speed and reliability, ease of use, its ability to eliminate traditional sources of dilution errors and an 85% reduction in consumable costs compared to their existing system that uses prefilled cups.
In comparative tests, the verifications of serial dilutions were performed with test tubes (standard method), with the existing Aargau system and with the Inlabtec System followed by viable cell counts of E. coli, B. cereus and Coagulase-Positive Staphylococci. The three tested serial dilution methods resulted in identical viable cell counts. Over several months of testing – a laboratory workstation was equipped with an Inlabtec Serial Diluter, which enabled a direct comparison with the existing systems using prefilled cups. In this comparison the Serial Diluter convinced by its ease of use and by the reliable working process which completely excludes dilution errors.
As another big plus proved the optimized use of resources, e.g. significantly less waste and storage volume, lower transport costs, which is a plus for the environment as well as for the laboratory due to lower costs.
More information on request