Using Superficially Porous Particles and Ultrahigh Pressure Liquid Chromatography in Pharmacopeial Monograph Modernization of Common Analgesics

High-Throughput Capillary Liquid Chromatography Using a Droplet Injection and Application to Reaction Screening

The cycle time of a standard liquid chromatography (LC) system is the sum of the time for the chromatographic run and the autosampler injection sequence. Although LC separation times in the 1-10 s range have been demonstrated, injection sequences are commonly >15 s, limiting throughput possible with LC separations. Further, such separations are performed on relatively large bore columns requiring flow rates of ≥5 mL/min, thus generating large volumes of mobile phase waste when used for large scale screening and increasing the difficulty in interfacing to mass spectrometry. Here, a droplet injector system was established that replaces the autosampler with a four-port, two-position valve equipped with a 20 nL internal loop interfaced to a syringe pump and a three-axis positioner to withdraw sample droplets from a well plate. In the system, sample and immiscible fluid are pulled alternately from a well plate into a capillary and then through the injection valve. The valve is actuated when sample fills the loop to allow sequential injection of samples at high throughput. Capillary LC columns with 300 μm inner diameter were used to reduce the consumption of mobile phase and sample. The system achieved 96 separations of 20 nL droplet samples containing 3 components in as little as 8.1 min with 5-s cycle time. This system was coupled to a mass spectrometer through an electrospray ionization source for high-throughput chemical reaction screening.

Exploring the Implementation of Compact Chromatographic Instrumentation in Common Analytical Workflows

In many industries, the concepts of “smaller,” “faster,” “easier to use,” and “cheaper” are key drivers when developing new technologies. The world of chemical separations is no different. Today, compact chromatographic instrumentation is being implemented in many workflows, as illustrated here through various examples.

Recent advances in analytical techniques for high throughput experimentation

High throughput experimentation is a growing and evolving field that allows to execute dozens to several thousands of experiments per day with relatively limited resources. Through miniaturization, typically a high degree of automation and the use of digital data tools, many parallel reactions or experiments at a time can be run in such workflows. High throughput experimentation also requires fast analytical techniques capable of generating critically important analytical data in line with the increased rate of experimentation. As traditional techniques usually do not deliver the speed required, some unique approaches are required to enable workflows to function as designed. This review covers the recent developments (2019-2020) in this field and was intended to give a comprehensive overview of the current "state-of-the-art."

Strategies in developing high-throughput liquid chromatography protocols for method qualification of pharmacopeial monographs

Method qualification is a key step in the development of routine analytical monitoring of pharmaceutical products. However, when relying on published monographs that describe longer method times based on older high-performance liquid chromatography column and instrument technology, this can delay the overall analysis process for generated drug products. In this study, high-throughput ultrahigh pressure liquid chromatography techniques were implemented to decrease the amount of time needed to complete a 24-run sequence to identify linearity, recovery, and repeatability for both drug assay and impurity analysis in 16 min. Multiple experimental parameters were tested to identify a range of experimental settings that could be used for the sequence while still maintaining this fast analysis time. The full sequence was replicated on a different system and with different columns, further demonstrating its robustness.