UV Channels
The purpose of this device is to assure detection for variety of analytes and extremely wide concentration ranges. For instance, 250nm UV channel detects p-Toluic acid ( lmax = 242nm, e = 14400) in ethanol from 1mg/L to 200g/L with a signal to noise ratio better than 10:1.

No reference cell is implemented for both UV channels. However, the drift is minimized to the extent that zeroing is never needed. Apparent variance of quartz cell transmittivity due to variable refractive coefficients of the solvent is continuously accounted for during data acquisition.

Deep UV LEDs employed as light sources eliminate the need for warm-up time. The unit is instantaneously ready when powered on. Also, LEDS have much longer life span than gas discharge lamps. Another important feature of this device is the reliable suppression of spurious signals from multiple gas bubbles which are very common in a preparative column effluent.

1. No column effluent split is required.  Flow rate is up to 120mL/min can be achieved with the minimum hydrodynamic resistance.

2. An adapter, provided with the detector, connects a conventional glass flash chromatography column to 1/16” or 1/8” plastic tubing.  4 ft of 1/16” and 4ft of 1/8” teflon tubing are provided with the detector.  Note, that metal tubing should not be used with this adapter.

3. Standard 1/4" x 28TPI FPLC inlet and outlet allows for direct attachment to most FPLC systems.  The Detector also has following connectors provided: two 1/16” plastic tubing; two 1/8” plastic tubing; two male Luer lock, two female Luer lock.  Note, that metal tubing should not be used with these connectors.

List of Supplied Parts (4-Channel)
1. RD4-250-280-RI detector unit
2. Two 1/16 tubing connectors with ferulae
3. Two 1/8 tubing connector with ferulae
4. One male Luer lock connector, PEEK
5. One female Luer lock connector, PEEK
6. Glass column connector, PTFE/Nylon-12, with two sets of three Viton o-rings
7. PTFE tubing 1/16” (1/32” bore) 4 ft
8. PTFE tubing 1/8 (1/16” bore) 4 ft
9. US style power cord, 3ft

"Now with the revolutionary new Centrifan PE, we can remove solvents much faster and safer."

Dr. Jianxin Chen, Brunswick Laboratories

About: Brunswick Laboratories is a Massachusetts-based independent contract laboratory and research organization providing analytical and R & D services to the nutraceutical, pharmaceutical, food and cosmetic industries.

Problem: Brunswick Laboratories utilizes the Yamazen Automated Flash Chromatography System (AI-580) with Luknova and Agela normal phase / reverse phase columns (C18 and HILIC) in their chemistry Lab. Multiple fractions are typically collected after the Flash LC run and solvents must be removed from the fraction collection tubes prior to advancing the sample to the next analytical step. They used a conventional rotary evaporator to accomplish the solvent removal task. The process was slow as the rotorvap could only process one fraction at a time and the instrument cumbersome for the task at hand as it required coolant and a vacuum connection. They were also concerned with bumping and splashing that sometimes occurred during the rotorvap process that could destroy valuable samples.

Solution: Brunswick Laboratories turned to the Centrifan PE Personal Evaporator as a fast, safe way to remove solvents from multiple fraction collection tubes simultaneously. The Centrifan PE employs a novel, recirculating evaporation technique that operates without vacuum and eliminates the potential for cross contamination and sample loss caused by solvent bumping or splashing. As a result, Brunswick Laboratory has improved lab productivity by substituting the rotorvap with the Centrifan PE. They are able to dry more samples in less time and no longer risk losing valuable samples caused by vacuum-based evaporation techniques.

"This unique instrument works very well. It is smooth and quick, no bumping or splashing, and can evaporate multiple fraction tubes simultaneously instead of drying the tubes one at a time on a rotorvap," said Dr. Jianxin Chen, R & D Director, Brunswick Laboratories.

For more info on the Centrifan PE: http://www.sorbtech.com/catalog.aspx?family_id=1696

Reversed Phase Silica Maintenance Procedures
In liquid chromatography pharmaceutical processes, there are 4 procedures, which are operated for GMP to ensure a maximum of reliability in the final product obtained.

1.    Regeneration:
Normally operated with a more polar solvent, 2 column volumes are enough to remove low migrating and/or strongly bounded impurities from the surface of the RP silica.
This procedure intends to retrieve the original capacity of the RP silica.

2.    Re-equilibration:
After the regeneration, the RP silica should be returned to the starting conditions of the chromatography run before the next injection, 2 to 3 column volumes with a short gradient are recommended and often necessary to get and warranty base line UV detection returned to the starting conditions. This procedure ensures the efficiency for the next run.

3.    Cleaning:
After a certain number of cycles, dependent of the raw material injected (feed stream), it is necessary to regularly proceed with a “cleaning step”. Most of the time reversed flow in the column is chosen with an adapted protocol.

4.    Sanitization:
Between batches, it is recommended to ensure column integrity to perform sanitization cycle to prevent microbial growth and cross-contamination from batch-to-batch.
It is recognized that sodium hydroxide (Na OH) solution 0.1 to 0.5 M is one of the most popular sanitizing agent, its effectiveness, low cost and low toxicity are especially attractive for process chromatography.

Despite extensive bonding chemistry with end-capping protecting the silica, the silica is dissolved at high pH, thus decreasing the lifetime of the RP silica. One method, developed some years ago by Grace-Amicon, (Journal of Chromatography, 503, (1990) p.385-401) utilized the addition of aluminium salt (ion) to mediate the action of the sodium hydroxide during the sanitization cycle.

The experiment in this publication shows that after more than 100 wash cycles with 0.1 to 0.5 M Na OH containing 0.005 M Al NO3, there is no “detectable” deterioration of the silica bed.

Recommendation:
In any case the contact time with NaOH solution should be maximum 30 minutes, and by reversed flow (after the Cleaning cycle) to ensure a maximum of efficient sanitation. It is preferable to decrease the flow rate and to elute half of the column volume with NaOH solution, followed by a strong polar solvent such as methanol or acetonitrile.

For more info: http://www.sorbtech.com/catalog.aspx?family_id=1667

WEBINAR: 9/21/2011 VP David Schurer introduces new webinar series on TLC-to-Flash Chromatography

http://www.sorbtech.com/video.tlc-flash-chromatography.aspx

Silica XG layers have a newly developed binding agent that makes it adhere to the aluminum substrate more strongly than the Silica G layers.  This equates to less flaking of the coating.

For these TLC plates a silica gel with a 60Å mean pore diameter, a 500m2/g specific surface area, a 0.75 ml/g specific pore volume, and a particle size of 5-17um is used.  Fluorescent indicator (UV254) and pre-cut sizes are available.

Silica XG: This is a soft layer plate that contains Gypsum.

For more info: Silica XG TLC Plates http://www.sorbtech.com/catalog.aspx?family_id=1671

Sorbtech VP David Schurer discusses Mitsubishi’s line of Ion Exchange resins

Sorbent Technologies offers a complete selection of aluminum oxide (alumina) products designed to perform simple to complex analytical and preparative chromatographic techniques for laboratory, pilot, and industrial process applications.  Our full range of standardized aluminas are available with defined activities, pH values, and particle sizes.  All of our aluminas are manufactured using GMP standards ensuring the highest performance and lot-to-lot reproducibility with no scale-up limitations. 

Our selection includes Aluminas for:

• Standard Chromatographic Techniques:  Flash Chromatography, Classic Column Chromatography, MPLC, HPLC, TLC, and DCC.
• Special Techniques:  Removal of Peroxides from Solvents, Purification of Solvents for UV-Spectroscopy, Natural Product Purification and  Decolorization, Heavy Metals Removal, Clean-up, Dioxin analysis, and Technique of Isotopes.
• Custom Aluminas:  Modifiable porosities, surface area, and particle distributions, Colloidals.  Inquire.

I want more information on Alumina for Chromatography and Industrial Applications

Sorbent Technologies offers a full range of standardized granular silica gels in three different grades:  premium, standard, and technical.

Granular or irregular-shaped silica gel is commonly used for the following applications:  Flash Chromatography, Classic Column Chromatography, and Medium Pressure Liquid Chromatography (MPLC).

Silica gels used for these applications are normally  60Å or sometimes 100Å.  For larger porosities please visit our Spherical Silica Gel pages.

Recommended Applications:

• Aflatoxins
• Chloramphenicol
• Pesticides
• Steroids
• Vitamins

For more info on Silica Gel, Granular for Chromatography

Sorbent Technologies VP David Schurer explains the use of our Silica Gel Selection Guide (http://www.sorbtech.com/silica-gel) for choosing the correct silica gel for your compound.

Our full range of standardized silica gels are available as granular (premium, standard, and economy grade) and spherical shapes with pore diameters ranging from 60Å to 1000Å, particle sizes from 3µm to 500µm, and bonded phases from C18 to SAX.

All of Sorbent Technologies’ silica gels are manufactured using GMP standards ensuring the highest performance and reproducibility with no scale-up limitations.
 
Certificates of analysis and individual data sheets are available for each product upon request.  Inquire about custom products.  We have available silica gel products for Flash, Classic Column, MPLC, HPLC, TLC, and DCC.