Hui-Chen Stavros


Elliott Williams

传统的农药分析是一个众所周知的time-consuming task, with the more rapid alternative – testing for multiple pesticide analytes using individual neats simultaneously – often leading to mistakes and damaging the credibility of the analysis.

Ehrenstorfer博士, a leading producer of pesticide reference materials, has addressed the need for reliable multi-component chemical screening with the development of their innovativeSmart Solutions™ PestiMix Kits, a world first in the industry.

These PestiMix kits are mass screening and spiking method-validation products that combine 745 analytes for liquid chromatography (LC) and 431 analytes for gas chromatography (GC) in just five ampoules, offering the largest mix of pesticide analytes on the market. It takes three minutes to create a single solution of up to 745 analytes at 1ppm and calibration can be carried out in just 30 minutes.

Hui-Chen Stavros and Elliott Williams, two members of the LGC facility in Charleston, which was responsible for the development of this unique tool, reflect on the key moments that sparked its inception and discuss how it can address challenges in the pesticide industry.


ew:We consider the industry as an ever-evolving organism. There are always new products being developed that bring a new range of analytes to deal with – and it’s all fuelled by innovation and hard work from start to finish.


Regulatory changes within this industry have surely added many challenges to testing labs. Can you outline why reference materials are key to this market?

HS:Reference materials, also called control standards, are used to check the quality and tractability of products, to validate the instrument methods or calibrate the instrument.

The reference material will ensure the accuracy and comparability of analytical data, regardless of application. This is extremely important to food safety and environmental testing.

“Ehrenstorfer quality” is considered one of the foundations for Dr. Ehrenstorfer products, but how vital is quality in reference materials?


What challenges would you say testing labs face on a daily basis?

HS:From the food safety point of view, the extraction of different matrices is the first challenge for the testing lab. A lack of appropriate reference standards or the detection limit of the instruments, especially water samples for the environmental testing lab, can also be challenging.

ew:我还要补充一点,主要的挑战之一可能是分析实验室必须测试的材料的不断增长的目录 - 这些材料中的每一种都有其自身的挑战,以确保质量和安全性。

Where was the gap in the market that you wanted to address?

ew:It was really hard to find a large stable mix of multicomponent compounds. I mean, the LC PestiMix kit is 745 compounds – that’s unheard of! Most compounds you find have four or five compounds in a mix, so this really did innovate in this space. Not many companies are willing to put forth the effort to make such a large mix. It’s definitely a daunting task and we don’t have very many other products in our product line that match this. But as we’ve learned, it is possible so we’re definitely trying to reach out.

What was the ‘Eureka Moment’ that triggered the inception of the first Smart Solutions™ PestiMix Kit?

HS:In early 2017, we received an order of 30 custom pesticide mix solutions. The most efficient way to verify the concentration of products was to compare them to independently prepared calibration standards. Based on the need of the Quality Control (QC) department, we decided to combine some of the mix solutions and that is what became the first generation of LC mix solutions, with over 500 compounds. At the time, the solutions were only used in-house. However, with the increase of custom solution requests, we felt it was the correct path for the QC department to design the calibration解决方案。

ew:Yes, and then PestiMix arose from the need to keep up with production. It was not feasible for us to continuously run hundreds of different check standards for everything, it was just eating up time. We started by just combining a couple of solutions and little by little it built up to a larger entity. Suddenly we were like ‘Oh, we’ve got something!’ and it just took off from there – I think that was the ‘eureka moment’.

Tractor spraying pesticides on vegetable field

Source: © Shutterstock

Farmers depend heavily on synthetic chemical pesticides. However, it is challenging to keep the balance between pesticide management and crop yield.

Which industries do the PestiMix kits have applications in and what challenges do they help to solve?

HS:食品安全和环境测试都是Pestimix的主要市场,主要动力是满足法规并节省大量时间 - 这两个套件中有1000多个分析物。

ew:Yes, our primary goal was to facilitate food testing, but I can definitely see PestiMix being applied in a multitude of other areas, like water testing too. Inaccuracy and inefficiency are the main challenges in these industries. And, with PestiMix being incredibly fast, very accurate and very stable, many industries can see huge benefits in workflows and lab routines.




You have also launched your new Smart Solutions v400 GC PestiMix Kit. Can you tell us what sparked this evolution from the original kit? How does it differ?

HS:The v400 GC PestiMix kit is designed for analytes that are more suitable to run by the GC/MS analytical technique due to their compound classes and solubility. The original PestiMix is more applicable for LC/MS analysis. Similar to the approach of LC PestiMix, the QC department also developed the GC PestiMix with the same idea. Again, it was actually the QC calibration standard in-house, then it was modified into a marketable product.

如果在其他市场(例如不断增长的大麻市场)中有必要,我们可能可以解决 - 我们一定会尝试

With every success story there are challenges, can you tell us about any moments during the process where you felt disheartened? Any times you had to go back to the drawing board?

ew:有很多次我们不得不回到drawing board. We had failed solubility fields and stability cross reactions were just everywhere. You’d be going down a list of data and you start seeing trends of entire compound classes – you just have to pull back out of that mix, start over from scratch and carry forward. There were a lot of issues, but over time it built up into something that you knew was going to happen and something you could account for a little bit.


ew:I think as more and more pesticides are used; we’re going to see a growth in the catalogue. If there’s a need in other markets, such as the growing cannabis market, we can probably tackle it – we will definitely try. In the future, we would like to continue adding to our kits to meet the expectations of our key markets– ultimately, our offerings will grow with these markets and grow to others. Only time will tell.


About the authors

Hui-Chen Stavros

Hui-Chen Stavros

Hui-chen是LGC Charleston的质量控制经理。她于1995年获得台湾台北医科大学的药学学位,并于1997年获得台湾国家国家的MS学位。该研究重点是海龟中的污染。她曾在国家海洋和大气管理局(NOAA)担任2005年至2008年的博士后研究员,研究海洋哺乳动物中的微量元素污染。她于2008年加入O2SI Smart Solutions(O2SI),担任化学家。她拥有15年以上的各种仪器经验:ICP,ICP-MS,AA,IC,原子荧光,HPLC,UHPLC/HRMS,GC/FID和GC/MS。当不工作时,她喜欢和家人一起观看棒球和旅行。她还说流利的普通话中文。

lliott Williams

Elliott Williams

Elliott is a Quality Control Chemist at LGC Charleston, USA. Elliott earned his BSc in Chemistry before beginning his journey into the world of analytical chemistry at o2si Smart Solutions. There he helps create and ensure high quality reference materials for the global market.