High sensitivity gel permeation chromatography for agrochemical analysis

In 2015 Syngenta, a leading agricultural company decided to purchase an OMNISEC Gel Permeation Chromatography (GPC) system from Malvern Panalytical. Here, Dr Kirt Durand, Senior Analytical Chemist at Syngenta discusses the decision-making process, the use of OMNISEC and his experience of working with Malvern Panalytical.

‘We already have many Malvern Panalytical systems in our company, primarily for particle sizing but also rheology, so when it came to upgrading our GPC capability we were keen to take a look at OMNISEC,’ says Dr Kirt Durand, Senior Analytical Chemist, Syngenta, US. ‘A GPC system is a major investment and we knew from previous experience that we could rely on Malvern Panalytical for truly excellent support. The OMNISEC is a great instrument but it is Malvern Panalytical’s service through the buying process that really sets the company apart from other vendors. That service has been consistent throughout this purchase and we’re confident we made the right choice.’

Time to upgrade

Syngenta manufactures a wide range of agrochemicals including pesticides, fungicides and herbicides, many of which are formulated as liquid suspension formulations. Polymeric components of such formulations include: dispersants; wetting agents; viscosity/rheology modifiers; buffering agents and anti-foaming agents. Ensuring consistency in these polymeric ingredients is essential for overall product quality control.

‘We’re a central analytical facility for the company,’ says Dr Durand ‘so we see many different samples and apply a wide range of analytical techniques. GPC is vital for the polymeric components we analyze for determining molecular weight, molecular weight distribution and the amount of material present. We use it routinely to confirm that all the components in a formulation are in suspension, in the concentrations that they should be, most especially when we have a manufacturing issue, when we’re investigating an out of specification product, for example, or an unforeseen interaction between a product and its packaging.’

‘Our other key application of GPC is to analyze supplies from two manufacturers to determine if they are equivalent before we switch. Switching suppliers to improve production economics or supply chain security is a routine strategy, but we need to be confident that there will be no adverse impact on product quality. While a new supplier may appear to meet the same specification, some materials go on to produce an out-of-specification product and a consequent increase in the number of wasted batches. Being able to detect a supply that will perform poorly before it enters the manufacturing plant is by far the most efficient approach.’

‘Because of the way in which we use GPC data, high sensitivity is critical, and this was one of the criteria at the top of list when it came to refreshing our existing GPC capability. However GPC is not the fastest or most straight forward of techniques to implement – so we were also looking for systems that could make our day-to-day life easier.’

Choosing a new system

Though Syngenta had used a Viscotek TDA-305 (Malvern Panalytical) multidetector system in the past, the net was spread relatively wide when it came to assessing the latest GPC systems available and a number of vendors were approached.

‘When it came to assessing OMNISEC, we could instantly see major performance improvements compared to our old TDA,’ continues Dr Durand ‘Key features for us were the significantly improved sensitivity, the heated autosampler and the ease of column changeover – a major benefit for a lab that handles many different samples. The new software was also a big attraction since we could easily see how this would enhance efficiency, making it easy to gather data and produce closely customized reports.’

However, beyond instrument performance, it was Malvern Panalytical’s approach to the sales process that set it apart from other vendors.

‘Malvern Panalytical has an open and flexible approach to the sales process, and invited me to give the OMNISEC a ‘test drive’ during a full day demo, at the company’s Houston site (Texas, US). A GPC system is a major investment, so being able to try a potential purchase for myself was really important. The demo made me feel comfortable about how easy the instrument would be to use and how straight forward it would be to gather and analyze the data we needed. And this approach is testament to Malvern Panalytical’s confidence in their product, since you can clearly find out exactly what the instrument can, and can’t, do!’

Sensitivity, productivity, ease of use – all up!

‘Since we purchased OMNISEC, we’re able to deliver more sensitive GPC data, so our ability to support decisions around different suppliers and troubleshooting has been directly enhanced. Day-to-day practice in the lab is also better. Switching columns is much faster and it is now far easier for us to present data in a way that our staff find easy to use. In an analytical lab like ours that operates so many techniques with relatively few people, improving productivity is a major gain. And it’s simply more rewarding to work with an instrument that is easier and more enjoyable to use, and frees up your time for higher value, more rewarding work.’

‘The bottom line is that OMNISEC has delivered exactly what we expected and we’re very happy with it. We’ve had great customer service from Malvern Panalytical throughout the sales process,’ concludes Dr Durand. ‘Most of our applications are relatively straight forward, but the Malvern Panalytical application specialist has been extremely responsive whenever we’ve needed help. All in all a really nice upgrade of a technique that is vital to our work.’ 

Malvern Panalytical’s OMNISEC GPC system enables the measurement of absolute molecular weight, molecular size, intrinsic viscosity, branching and other parameters and is a powerful tool for taking control of the performance, quality and value of polymeric products. To find out how OMNISEC could help you, Click Here.