The shift from HPLC to UPLC: The industrial perspective

Manu Grover

The Indian industry is at a turning point, with large enterprises beginning to recognise that the drivers for success are shifting away from conventional saving procedures onto concepts like productivity enhancement, faster decision making, shorter time to market, lowering the cost of analysis and manpower empowerment. With new opportunities in global market, new investments are being considered under an ‘future proof’ concept.

In the late 90’s the technology vendors or the bio-suppliers were merely considered as general suppliers and now the enterprises considers these vendors as their partners in quality, compliance and research. The business model from product management and brand management is now being shifted to value management. As per the current trends, enterprises like to partner with those vendors or bio-suppliers who can not only give quality products but also can add value to their business and research through programmes like compliance education, application trainings, regulatory updates, technical works-shops etc.

Waters has always been considered as an innovation leader and trustful partner in analytical industry. Waters revolutionised column technology and introduced columns with particle size from 10/5 µm to 3.5 µm and then to 1.7µm. To leverage upon these small particles, Waters introduced about 10 years ago Acquity UPLC system. These systems have higher pressure handling solvent management system and reduced system volumes than the conventional LC systems. The column and instrument related innovations led to improvement of the chromatographic performance w.r.t. sensitivity, speed and resolution. The development in column chemistries continued at Waters and now Waters have more than 16 scalable UPLC-based column chemistries. The latest in portfolio is Cortecs columns featuring the ‘solid core technology.’

In-order to effectively utilise the power of smaller particles 1.7µm, we require a LC system that operates at higher pressures and is designed with lower dwell and dispersion volumes. Hence, in UPLC, the extra-column volumes were minimised. The retention time precision remains extremely important under UPLC running conditions such as high pressures and low flow rates. The Waters Acquity UPLC system uses an automatic and continuous compressibility compensation algorithm that does not require user intervention to cope with these demands, resulting in retention time reproducibility. Also, electronically controlled intelligent check valves in solvent management system ensure improved performance and priming reliability. Waters has introduced UPLC platforms in all areas of research and quality control Like Quaternary UPLC (H-Class), Binary UPLC (I-Class), two-dimensional chromatography (2D-UPLC), Nano-chromatography (M-Class), Super critical fluid based chromatography (UPC2) and PAT-based UPLC for on-line analysis (PATROL)

Acquity H-Class and H-Class Bio are the UPLC’s with quaternary solvent management system for small molecules and large molecules analysis respectively. With in-built feature to assist in solvent, pH/salt blending and method transfers, Acquity UPLC are most reliable instrument in their class. UPLC H-Class, has capabilities of performing both UPLC and HPLC applications. This flexibility has translated UPLC H-Class technology in-to a best example of ‘Future-proof’’ investment in pharmaceutical industry.

UPLC usage has increased significantly in both API and Formulation industries. The savings (time and cost) associated while performing the typical tests such as reaction monitoring, assay, dissolution and related substances during the release and In-process testing by UPLC is significantly high. The saving in time in R&D leads to faster product development hence ‘early to market.’ In quality control labs, saving in time during analysis leads to decrease in quarantine time of intermediates, reduced shifts, faster release of batches for In-process testing and hence ‘faster to market.’

Acquity UPLC I-Class is the current choice of analysts for LC as an MS inlet. It has lower dispersion and dwell volumes and also higher pressure limit of 18000 psi. This system can be used to run gradient programmes of one minute and below. This leads to faster analysis and higher throughput. This advancement has lead to increased implementation of Acquity UPLC I-Class as an MS inlet.

The QbD approach as emphasised by US-FDA during analytical method development process in their recently issued draft guidance on ‘Analytical Procedures’ dated February 2014 is an important reason for UPLC implementation in pharmaceutical R&D’s. QbD recommend to perform multivariate experiments by screening and scouting of different variables using DOE approach. screening-n-scouting can be done by using multiple buffers, solvents and column chemistries. UPLC H-Class with its additional method development modules like nine solvent selection valve and six column manager with independent column temperatures zones can lead to faster screening-n-scouting of the analytical methods than the conventional HPLC. (See figure 1)

Figure – 1

Any LC system in the pharmaceutical industry or research should be flexible w.r.t capability of handling multiple detectors and Acquity UPLC comes with wide range of detectors developed by Waters like UV, PDA, RI, ELSD, fluorescence and mass detectors. Historically, UV/PDA detection has been favoured in many laboratories for its ease of use, robustness, and reliability. However, some of the inherent challenges with UV/PDA during development include analysis of analytes that are non-chromophoric, confirmation of coelutions, Mass balance studies etc.

The challenges in UV-based developments can be resolved using orthogonal detectors like mass detectors. Waters introduced recently Acquity QDa Mass Detector, which have been purposefully designed to enable analysts to readily incorporate mass detection within a UV/PDA chromatographic workflow. The simplicity of this Single Quadrapole Mass detector is such that it can be handled easily by the chromatographers who have no MS trainings and are only UV/PDA users. QDa, the mass detector has the quickest start time, once switched on, the detector is ready to use in less than 25 minutes. QDa through Empower CDS software can enable scientists to do tasks like peak tracking, identify impurities/peaks, analyze non-chromophoric impurities, understand mass-balance related issues, perform MS finger printing, confirm peak purity data, etc. (See figure 2)

Figure – 2

The adoption of UPLC methods for various tests by different regulators like US-FDA, EMEA as release methods or alternative methods and adoption of UPLC by EP and USP in their monographs (NF and MC) clearly reflects the reason for the increase in trend w.r.t its implementation. Here are some of the products having official UPLC methods in USP- Glycopyrrolate, Tramadol HCl extended release tablets, Ganoderma Lucidum, Sulindac, Aminolevulinic acid, Schisandra Fruit, Almotriptan tablets. Reference UPLC methods official in EP are Quetiapine fumarate and Nevirapine.

The recent revision of USP Chapter <621> (See figure-3) allows the conversion of HPLC methods to UPLC without the need of complete validation.