Ongoing technological advances to high-performance liquid chromatography (HPLC) are contributing to more efficient, greener and ‘joined up’ laboratory processes, explains Shimadzu’s expert in the field.
Angela Jein [pictured above] is the liquid chromatography technical specialist at Shimadzu UK. It’s a vantage point from which to appreciate key developments within the field and the points at which techniques have undergone most rapid progress. A century ago, analysis centred on being able only to detect compounds but has since expanded “to achieving lower and lower concentrations, with proof that the compound is what we are trying to detect”.
Mass spectrometry has played a key role in this advance, Jein explains: “Mass spectrometry enables either the confirmation of your compound or detection at low levels. The improvements within the mass spectrometry technology are reducing the concentration levels we can see and improving the mass accuracy. These allow for more certainty that compounds are analysed correctly and are further aided with the use of the latest technology.”
The initial drive of including analytical intelligence to improve efficiency and throughput has gone a step beyond by using other automated processes and robotics to combine technologies ready for the future steps of analysis
High performance liquid chromatography (HPLC) was a milestone in the development of liquid chromatography techniques that had been previously dependent on gravity for operational pressure. Significant strides were made in the mid-20th century; Industry 4.0 is providing a further step change. “The most recent focuses of innovations are analytical intelligence, looking at how software and hardware features can maximise the output from each instrument. Hardware improvements are now allowing for ultrafast analysis of multi compound mixtures. Instrumentation can now be used to analyse two different methods using the same sample and instrument. All of these advances aid traditional HPLC with techniques such as supercritical fluid chromatography (SFC) and preparative analysis.”
As elsewhere, 4.0 has brought the benefits of unprecedented scale and speed, heralding the advent of ultra-high performance liquid chromatography (UHPLC) where, says Jein, analysis of compounds has moved from analysing a few to vast quantities of samples.
“The advancement of the HPLC technique to UHPLC allows for a dual benefit of increased speed of analysis, thus increasing the throughput and the number of samples you can analyse in the same time period; as well as increased resolution of peaks, allowing for more compounds to be analysed and/or more sensitivity to see compounds at a lower concentration before the need for additional detection techniques.”
Technological advances go beyond enhancing the ability of individual tools and processes to perform faster and at a greater scale.
A key characteristic of the fourth industrial era is its ‘joined up’ aspect. So how does she see this contributing to the automation and integration of chromatography in the modern laboratory?
“Modernisation has certainly always been a driving factor within analytical instrumentation and both Lab 3.0 and Lab 4.0 drive the automation process. The initial drive of including analytical intelligence to improve efficiency and throughput has gone a step beyond by using other automated processes and robotics to combine technologies ready for the future steps of analysis,” assesses Jein.
Yet she acknowledges limitations to liquid chromatography, in particular if the compounds with which it must deal are volatile in nature or not soluble within commonly used HPLC solvents.
That said, adds Jein: “Advances in HPLC in general allow for techniques such as supercritical fluid chromatography, two-dimensional liquid chromatography or ultra-fast preparative and purification liquid chromatography, to drive the technique forward to allow the analysis of compounds that previously would have had to be analysed by different techniques.”
The advancement of the HPLC technique to UHPLC allows for a dual benefit of increased speed of analysis, thus increasing the throughput and the number of samples you can analyse in the same time period
The drive for throughput and sensitivity has fed development of modern instrumentation, explains Jein; it will see the inclusion of robotics in more automated processes and influence SFC, UFPLC and GC [chromatography] techniques, among others.
Finally, that watchword of the 21st century lab – sustainability: What does the concept of green chromatography look like to her?
“Analysis from the late 20th century was typically 30-60 minutes an injection at 1 mL/min, the current HPLC analysis is 15-20 minutes with UHPLC ranging from 1-10 minutes at lower flow rates,” says Jein. “Compounds are being analysed in quicker analysis time and lower flow rates reducing the energy consumption and solvent use. The drive to move away from longer methods and for greener solvent use work well with automation to ensure the systems are shutdown at the end of use and consume less power.”