High Resistance to Solvents 

The COSMOSIL CHiRAL series uses a chiral selector that is chemically bonded to the silica gel, which results in high resistance to solvents. Tetrahydrofuran (THF) strips coated selectors from the stationary phase, reducing theoretical plates to less than 1/5 in our experiment. However, the same selectors bonded to the silica withstood repeated injections of THF.

Due to its immobilized selectors, various solvents are usable with COSMOSIL CHiRAL. A wide variety of solvents increases your selectivity options.

The COSMOSIL CHiRAL 3 series (3 μm particles) puts moderately higher pressure on the system compared to conventional 5 μm particles. This improves reproducibility for low-pressure solvents, such as hexane, that may otherwise cause pump irregularities. As shown in the figure below, increased 2-propanol concentration causes higher pressure. However, even at 50% (v/v), the pressure did not exceed 12 MPa. At the lowest concentration of 5% (v/v), the backpressure was 5.3 MPa. This range allows high flexibility in mobile phase composition and selectivity.

The COSMOSIL CHiRAL 5 series (5 μm particles) is equivalent to other companies’ immobilized polysaccharide derivative-based chiral columns. 

The same chiral selector will yield similar separation patterns. In general, Enantiomers that can be separated on a coated selector can also be separated on an immobilized selector, and those that cannot be separated on one will not be separated on the other. 

COSMOSIL CHiRAL offers 3 different chiral selectors that, together, have a high probability of separating your sample. Of 28 samples in our test, 27 pairs of enantiomers were fully separated. For samples that do not separate easily with any column, please adjust the type and concentration of solvents in your mobile phase. 

Available in 3 μm Particles

Sharp Peaks

COSMOSIL CHiRAL columns are available in 3 μm particles, which yield sharper peaks than conventional 5 μm particles. Columns for preparative separations are available with 5 μm particles.

One of our customers has succeeded in separating Δ-9-THC and CBCA enantiomers using our CHiRAL 5A column.

Cannabinoids of various types have recently become compounds of interest with the potential to treat various ailments. As many of these compounds have optical isomers, separation these enantiomers could prove to be important to research into their therapeutic potential.

 delta-9-Tetrahydrocannabinol (Δ9 THC) Enantiome

Cannabichromenic Acid (CBCA) Enantiomers 

Naringenin is a chiral flavonoid found in foods such as tomatoes and citrus. In vivo studies have shown positive health effects such as anti-inflammatory, anti-bacterial, anti-tumor, and antioxidant properties. One limitation of current studies is the lack of chiral characterization. While it is known that the S enantiomer is the natural product, the ratio of enantiomers in foods has not been studied. There is no data as to whether S-naringenin's enantiomer has positive or negative effects. To better characterize naringenin as a potential pharmaceutical, a detailed method is presented here for the chiral analysis of racemic naringenin using Cosmosil CHiRAL series HPLC columns.

Figure 1: Analysis of racemic naringenin on columns with three different chiral stationary phases. Cosmosil CHiRAL B shows significant resolution of the enantiomers compared with CHiRAL A and C.

Acquisition Method: Column: CHiRAL A, B, or C Column Size: 4.6 x 250 mm Mobile Phase: Water : Acetonitrile 35:65 Flow Rate: 1 mL/min Temperature: 50°C Detection: UV 275 Sample: Racemic Naringenin 1 mM in ethanol Inj. Vol.: 1 µL

COSMOSIL Application Data

COSMOSIL Application, which includes more than 7,700 applications using COSMOSIL/COSMOCORE columns, is now usable by clicking the link below which is in Nacalai Tesque, Inc. The application is searchable by sample category, sample name, CAS No., column name and particle size