Deuterium Lamp (PDA Plus)

Over time, exposure to ultra violet (UV) ,radiation from the sun or tanning beds can ,damage the skin’s cellular DNA, resulting in ,mutations that cause 3.5 million cases of skin ,cancers and about 11,500 deaths in the U.S. ,each year, for a total cost of nearly $2 billion. ,There are three types of UV: UVC, UVB, and ,UVA.

Biocides are chemical substances that are used to kill or inhibit harmful organisms. Biocides have a wide range of applications in consumer and industrial products.

This application will focus on the solid phase extraction (SPE) and HPLC analysis of chlorophenols in three tap water samples.

Phenolic antioxidants and ascorbyl palmitate are commonly used in food to prevent the oxidation of oils. Oxidized oils cause foul odor and rancidity in food products.

In 2009, the United States Pharmacopeial Convention introduced the USP Dietary Supplements Compendium (DSC) – an industry directed resource featuring regulatory guidance, documents, supplemental information, and reference tools.

Ginseng has been used as an herbal medicine in Asia for over two thousand years for its purported various health benefits, including, antioxidant, anticarcinogenic, antiinflammatory, antihypertensive and anti-diabetic. The pharmacologically active compounds behind the claims of ginseng’s efficacy are ginsenosides; their underlying mechanism of action although not entirely elucidated appears to be similar to that of steroid hormones. There are a number of ginseng species, and each has its own set of ginsenosides.

The goal of this work was to develop a simpler, faster and reliable LC method for the analysis of the six most widely-used isoflavones in soy products.

Foods from plants are complex mixtures of chemicals including both essential nutrients and biologically active non-essential nutrients, referred to as phytochemicals.

The focus in this work was to develop a simple, robust, and reliable LC method for the analysis of patulin in apple juice.

With the focus on possible vanilla extract adulteration, this application focuses on the HPLC separation and quantitation of vanillin, ethyl vanillin, and coumarin in three store-bought vanilla extracts.

Patulin is produced by various molds, which primarily infect the moldy part of apples. Removing the moldy and damaged parts of the fruit may not eliminate all the patulin because some of it may migrate into sound parts of the flesh.

This application describes an analytical method for the chromatographic separation and quantitative monitoring of seven primary cannabinoids, including THC and THC-A, in cannabis extracts by HPLC with PDA detection. Naturally occurring cannabinoids, the main biologically active component of the cannabis plant, form a complex group of closely related compounds, of which 113 are known and 70 are well described. Of these, the primary focus has been on ?9-tetrahydrocannabinol (THC), as the primary active ingredient due to its pharmacological and toxicological characteristics, upon which strict legal limits have been enforced.

One essential aspect of the quality control in beer brewing is making sure that the type and

Sweeteners are low or zero-calorie sugar substitutes that are added in drinks, processed foods and pharmaceutical products to provide the sweet taste of table sugar, which is also called sucrose.

Heightened awareness of polycyclic aromatic hydrocarbons (PAHs) has become prevalent due to urban background levels found in surface water, soil, air, cosmetics and food. They are generated by the combustion of fossil fuels and are always found as a mixture of individual compounds that differ in behavior, environmental distribution, and their effect on biological systems. PAHs encompass a wide molecular weight range, differing based on their physical, chemical, and biological characteristics. PAHs in surface water result from a variety of sources including residential, industrial and commercial outlets, streets and parking lots, and atmospheric fallout. In this application, via a spiking experiment, we explore the levels at which PAHs in surface water can be monitored by UHPLC with a sub-2 µm particle sized column combined with photo diode array (PDA) and fluorescence (FL) detection.,

Presented is an alternative technique to quantitate benzodiazepines in plasma using a rapid protein precipitation method with a fast LC separation method in combination with TOF-MS.

This application note will present a fast, sensitive and reliable UHPLC analysis of six common parabens. A PerkinElmer Flexar FX-15 UHPLC system fitted with a Flexar FX PDA photodiode array detector was used. The separation was achieved using a PerkinElmer Brownlee Analytical C18, 1.9 µm 50 mm x 2.1 mm column.

Water polluted by herbicides leach and runoff can cause human health problems including cancer tumors, reproduction deformity, disruption of the endocrine system and DNA damage. This application presents a sensitive and robust liquid chromatography method to test nine widely used herbicides (Figure 1), using a 3 µm UHPLC column to achieve very high throughput at a low flow rate to reduce testing time and solvent consumption. The throughput is compared to that of a conventional C18 HPLC column. Method conditions and performance data including precision and linearity, are presented.

This application note presents a fast and robust liquid chromatography method to simultaneously test nine widely used additives. Among the additives tested are: preservatives (benzoic acid, sorbic acid, dehydroacetic acid and methylparaben); artificial sweeteners (acesulfame potassium, saccharin and aspartame); flavoring agent (quinine); and a stimulant (caffeine).

Individuals typically use 5-20 cosmetics per day, many of which contain sunscreen to prevent skin damage from the sun’s radiation, and antimicrobial preservatives called parabens. Although sunscreen-active ingredients are designed to block UV radiation, some cell damage may be caused when these ingredients are illuminated by sunlight after absorption into the skin. For example, oxybenzone, an ingredient considered safe by the FDA (Food and Drug Administration), is believed to contribute to the recent rise in melanoma cases by increasing the production of DNA-attacking free radicals upon UV exposure. Additionally, studies have shown oxybenzone to behave similarly to the hormone estrogen, suggesting that it may also contribute to the development of breast cancer. Parabens are absorbed through the skin via cosmetic applications and can be found in nearly all adult urine samples, with the highest concentrations observed in adult females and adolescents. Furthermore, parabens are thought to have estrogenic activity, which affects the expression of genes regulated by the natural form of estrogen, leading to early puberty in girls and an increased risk for the development of breast cancer.

Alpha acids (a-acids) are a class of chemical compounds of primary importance in the production of beer. They are found in the resin glands of the flowers of the hop plant (Humulus lupulus) and are normally added to the boil after mashing the grains, providing beers with their aroma and bitter taste. The a-acids found in hop resins are isomerized to form the iso-a-acids during prolonged boiling in the wort. The degree of isomerization and the amount of bitter taste produced by the addition of hops is highly dependent on the type of hop and the length of time the hops are boiled. Longer boil times will result in isomerization of more of the available a-acids, making the beer more bitter. The a-acid percentages vary within specific varieties of hops, depending on the growing conditions, drying methods, age of hops, climate and other factors. Figure 1 shows the common a-acids and iso-a-acids involved in the beer brewing process. Since the quality and quantity of a-acids is so important in consistently providing individual beers with their recognizable taste, it is essential to monitor their amount in hops and beers and to monitor the formation of the iso-a-acids during the beer brewing process. The focus of this application note is to provide an easy, straightforward, and robust analytical method for establishing the type and amount of a-acids in hops pellets, as well as determining the amount of a-acids and iso-a-acids in various beers.

Whether you’re a lab manager or a bench chemist, you know firsthand how things are changing quickly in food and environmental analysis. And your lab needs to change to keep pace.