Despite drastic reductions in pharmaceutical R&D headcount and spending, which have reduced growth, flash chromatography, a preparative LC technique, accounted for more than $100 million in annual revenues in 2009 (see table, page 6) and is expected to grow in the mid-to-high single digits.

Demand for flash chromatography comes mainly from the pharmaceutical, biotechnology and academic markets, with the pharmaceutical industry and related demand from contract research organizations (CROs) comprising nearly half the market. Pharmaceutical companies use flash chromatography for myriad applications, such as the purification of small compounds, peptides and natural products.

The pharmaceutical industry is becoming more reliant on techniques like flash chromatography, said Vikas Padhye, vice president of Sales, Marketing and Service at Teledyne Isco. The industry continues to look for options that will provide the same results with fewer resources. “The instruments need to get smarter with respect to automation and productivity,” he said. “They want to have the same quality results faster, so a lot of companies are focusing on that aspect.”

The biotech sector and emerging markets are currently experiencing the fastest growth, according to Joanne Green, vice president and general manager, Grace Davison Discovery Sciences. This is due to an overall trend toward compound diversification, requiring the purification of a new range of hard-to-detect molecules, she told IBO. In the US and Europe, the market is expected to remain essentially flat, said Dr. Padhye, because of the readjustment of pharmaceutical resources.

The leaders in the flash chromatography market are Teledyne Isco and Biotage. Both companies focus on automated systems and columns and media. Grace Davison is a major supplier of columns and media as well, with a more moderate focus on automated systems, while Merck KGaA and Sigma-Aldrich are focused on aftermarket. Other systems vendors in the flash chromatography market include Agilent, Büchi, Gyan, Interchim and Richard Scientific. Aftermarket sales make up more than half of the market.

Flash chromatography is a form of preparative LC that is commonly used to separate synthetic organic compounds simply and quickly. The low- to medium-pressure technique separates a sample by using a plastic column filled with a solid support, generally about 50 µm of silica gel. The sample is placed on top of the support, and the rest of the column is filled with either an isocratic or gradient solvent that drives the sample through the column, separating it. Automated systems can separate samples from a few milligrams to hundreds of grams.

Flash chromatography is a fast, inexpensive way to purify synthetic and natural organic compounds. “Flash allows chemists to quickly purify intermediates in their multi-step transformations that are critical in developing final new molecular entities,” said Ms. Green. “Flash can also be used to isolate minor impurities from API [active pharmaceutical ingredient] drug substances.” Flash chromatography is also used to isolate substances from food products. The compounds best analyzed and purified with flash chromatography include alkaloids, antibiotics, essential oils, enzymes, glycosides, lipids, hormones and oils. The technique is also useful for plant extraction, degradation of organic solvents and removal of peroxides.

The most popular alternative technique to flash chromatography is reversed-phase HPLC. HPLC is advantageous for a high degree of resolution. Flash chromatography does not match the performance of HPLC, but it is a viable option when higher amounts of compounds must be purified and the precision offered by HPLC is too costly and unnecessary. HPLC is also a more complicated technique that usually requires chemists to relinquish their sample to a separate lab to perform the purification, said Ms. Green. “Essentially, they must sacrifice simplicity and control,” she said, adding that flash chromatography “allows chemists to quickly and easily purify their own compounds.” Using either isocratic or gradient elution techniques, it is possible to separate an entire sample on a single run. “Flash is advantageous because the purification scale is larger, the process is faster, the sample loads are higher and the typically nonaqueous solvents are more easily evaporated than reversed-phase HPLC solvents,” added Bob Bickler, manager, Applications & Product Development Group, Biotage.

The development of flash chromatography appears to be following that of HPLC, such as moving from simple, isocratic purification to fully automated, high-performance chromatography using smaller particles, Mr. Bickler said. “Flash cartridge designers are pushing the limits of column technology by developing cartridges with small particles designed to provide higher-resolution separations,” he told IBO. Biotage’s SNAP HP-SIL cartridges and Teledyne Isco’s RediSep Rf Gold silica utilize 30 µm and 20–40 µm size particles, respectively, compared with 40–60 µm for the silica typically used. The smaller size particles are designed to improve resolution, increase fraction purity and separation efficiency, and reduce solvent usage.

Smaller size particles also enable the use of higher pressures. Originally, system pressure was around 50 psi. Instruments such as Grace’s Reveleris and Teledyne Isco’s CombiFlash Rf can now operate at 200 psi. “We have gone faster, more automated, with higher pressure, yet are keeping the simplicity that chemists want,” Dr. Padhye told IBO.

Flash chromatography vendors aim to improve technology without sacrificing system ease of use. “Flash 10 years ago was quick and simple,” said Dr. Padhye. “It is still quick and simple, but it is quick and simple and more using the latest technologies.” Systems now rely on multiple detection technologies, such as evaporative light scattering detectors (ELSD). “This gives chemists a single integrated system with the simplicity of traditional flash, but with the power and sophistication of more advanced chromatography techniques; hence, they can detect compounds and isolate impurities that cannot be detected with UV,” said Ms. Green. Biotage’s Isolera UV-VIS flash purification system adds a UV-Vis detector for the broadest wavelength detection flash system available , according to the company, detecting organic molecules with spectral absorbance between 200 nm and 800 nm.

As the technology evolves, more and more options for flash chromatography systems become available. “Flash system designers are introducing more capability into automated flash systems, including more detector options and increasing system intelligence, such as with creating an optimal gradient from TLC [thin layer chromatography] plate data and predicting sample load,” said Mr. Bickler. The separation achieved with a TLC plate can be analyzed to estimate the separation of a flash chromatography column. As a result, flash has become the scale-up technique in the purification of products first isolated using TLC. There are more than 30 phase chemistries with corresponding TLC plates.

Safety is another issue that vendors strive to improve upon. Biotage’s FlashMaster Personal Plus system uses a magnetically driven pump instead of external gas pressure to deliver solvent. The pump solves the safety issues associated with pressurized systems, the company said. Teledyne Isco’s CombiFlash Torrent’s solvent-sensing technology monitors solvent supply and waste to allow walk-away automation. The system also features pressure and vapor sensors for safe automation.

Smaller sized systems are also a market mainstay. Teledyne Isco’s CombiFlash Rf and Grace’s Reveleris measure 8.5 x 24 x 17 in and 16.5 x 21.5 x 18 in and weigh 54 lb and 75 lb, respectively. “There is increasing pressure on all laboratory environments to do more with less,” Ms. Green told IBO. “Space is often at a premium in drug discovery laboratories. Smaller instruments allow more efficient use of benchtop and hood space. Ergonomically advanced and compact systems also improve efficiency and safety.” In addition, Ms. Green said, smaller systems increase productivity, decrease waste, lower operating costs and lead to a more “green” approach to purification.

To remain competitive and distinguish their brand, vendors are focusing on different aspects of the market. Grace is focused on innovations such as its RevealX technology for the Reveleris system. Such innovations, said Ms. Green, have “transformed flash detection and collection. Multiple ultraviolet signals as well as ELS can be processed simultaneously. This allows chemists to quickly and easily purify highly complex samples.”

Biotage continues to hone its strategy of offering a complete product line for synthesis and purification. “Complementary techniques Biotage emphasizes are centered on the entire synthesis process,” said Mr. Bickler. “From Biotage, a chemist can obtain every tool required for a synthesis project, including a microwave synthesizer, sample work-up (i.e., catalyst and/or excess reagent removal), purification and evaporation equipment.” Biotage offers solutions for HPLC, solid phase extraction and peptide synthesis.

Teledyne Isco is focused on improving results for flash media. C18 does not always provide optimal results for purifying highly polar compounds, according to Dr. Padhye, so Teledyne Isco has introduced C18Aq media to perform reversed-phase purification with more efficiency. The media consists of C18 bonded to silica with modifications and can be used with all percentages of organic solvent. In particular, it has shown improvements in resolution for compounds where the solvent contains a high concentration of water.

According to Dr. Padhye, since flash chromatography is a pragmatic tool used for organic or natural compound purification, it will continue to find more acceptance. “As such, it will be a mainstay in any organic lab,” he said.

Table: Flash Chromatography Total Sales

2009 $102,000,000

2010 $109,000,000

2011 $118,000,000