Vitamin A & E Isolation Utilizing Advantage EluChrom from various solid and liquid samples.
Top Left: Centrum® Vitamin
Bottom Left: “Daily Vites” Liquid Gel Tab
Top Right: “Vita Vive” Hair Conditioner
Bottom Right: “Stress Relief” Body Lotion.
Extraction of various samples for the isolation of vitamins A and E using 12mL EluChrom cartridge and declining polarity solvents.
Chromatographic conditions: 5% H2O in 72.5:22.5 CH3CN:MeOH, 0.25mL/min, Advantage ARMOR C18 10cm x 2.1mm I.D. column. Diode array detection at 286nm.
Cartridge flushed with 2mL of MeOH followed by 2mL of distilled water. Sample was pulverized and charged onto cartridge. Both top and bottom caps were secured and the cartridge shaken for five minutes. Water layer is eluted off and discarded; next eluent is MeOH, followed by Ethyl Acetate. The ethyl acetate cut is filtered and transferred to the assay vial ready to be chromatographed. In some cases, an additional cut of chloroform may also be beneficial.
This is a normal phase separation. The most polar compounds such as the amino acids, and sugars isolate first followed by the medium polarity compounds, some fats. Lastly, the non-polar compounds, cholesterol products and fats appear.
We acknowledge Laszlo Treiber, Ali Shafiee, Tom Holt, Pilar Hernande
The aromatic hydrocarbons that most HPLC column manufacturers use to quality control columns render little information about a column’s selectivity and performance characteristics for peptides. The Canadian corporation, SPI, produces a well characterized yet challenging peptide mixture that is very useful for quantifying HPLC column performance for peptides. The difficult to separate first pair of peptides are resolved to near base line on Advantage HIGHLOAD C18 columns. Many so-called peptide analysis columns are unable to separate this pair.
Caffeine and Theobromine belong to a group of substances known as methylxanthines. Caffeine occurs naturally in coffee, tea, cola and to some degree cocoa beans. It may also be added to cola drinks and is a component of certain over-the-counter and prescription medications. Theobromine is found in cocoa beans; tea contains trace amounts. Although theobromine is chemically related to caffeine, it lacks caffeine’s stimulant effect on the central nervous system. In fact, theobromine is virtually inert as a CNS stimulant. Theobromine does however pose a toxicity issue in dogs. Dogs are unable to excrete these chemicals as efficiently as humans, and thus as the compounds travel via the liver and bile duct, they are converted back into the original methylxanthines for another circuit through the dog’s system. Instead of excreting the substance, dogs keep re-poisoning themselves. Listed below is a very simple yet robust method for extraction of methylxanthines from chocolate.
3cc EluChrom™washed with two column volumes of MeOH followed by two column volumes of HOH.
Add 10mg of pulverized chocolate, add 1mL of HOH, cap cartridge and shake for 5 minutes. Place cartridge on SPE manifold and drain off HOH extract.
Add 1mL MeOH and drain to waste. Add iml CH3CN and collect in 2mL sample vial.
The stability of the AGP column has been tested using bumadizon (an acidic drug) as a test compound. A total of 30.5 liters of mobile phase (10% isopropanol in phosph. buffer pH6.0) was pumped through the column. During the test 2030 samples of bumadizon were injected. The two chromatograms below are the first and the last obtained in the test. No significant changes were observed.
Today’s beaches are jammed with people who rely on sunscreens for a safe tan. Yet epidemiologists note that the rise in sunscreen use has proceeded in tandem with an increase in skin cancers. Sunscreens effectively block the ultraviolet B radiation that causes sunburn, but they don’t all shield the skin from potentially harmful ultraviolet A rays. Skin care companies are now formulating protection into other skin care products for additional protection. A simple method for extraction and assay of three main sunscreens is listed below. Extractions are of a moisturizing lotion and a lipstick.
Isolation Procedure: 3cc EluChrom™ washed with two column volumes of MeOH followed by two column volumes of HOH. Add 100mg homogenized sample to cartridge, add 1mL of ethyl acetate and collect in 2mL sample vial. 2µL of ethyl acetate cut is injected on to the HPLC system.