Liquid chromatography (LC) is a well-known extraction methodology which is widely utilized in the analysis of solutions, where the primary objective is to detect and quantify contaminant elements.
The basic premise of liquid chromatography revolves around the separation of a solution’s constituents by their ionic or molecular properties. This separation occurs when the sample is strategically injected into an LC column containing a separative stationary phase. Analytes pass through the column at different rates based on unique ionic/molecular interactions with the stationary media. Absorption rate, size, and a range of other factors dictate the speed at which solutes pass through the LC column. Operators can subsequently infer detailed chemical insights into sample composition based on time-dependent elution.
Various forms of liquid chromatography are useful in detecting contaminants and quantifying undesirable elements down to the trace and ultra-trace levels.
The Importance of Bisphenol A Extraction
Bisphenol A (BPA) is an industrial chemical found in various epoxy resins and polycarbonates. It is also remarkably similar to synthetic estrogen, and subsequently carries high potential health risks. BPA is said to mimic the body’s natural hormone responses and disrupt normal hormone levels. Too much BPA in the body carries significant health implications. This is problematic as BPA-containing plastics are routinely used in food and water storage.
BPA is a common additive used in the industrial production of polycarbonates and polyvinyl chloride (PVC). It is also an important monomer in the production of polycarbonate. Due to the number of essential uses, it is hard to eradicate from manufacturing chains. This makes detecting it in products for human consumption a necessity.
At Knauer, our team of experts deploy online solid phase extraction (SPE) for time-saving and trustworthy solvent separations for contaminant detection. As an automated liquid chromatography technique, SPE is extremely practical and perfectly suited to repetitive procedures such as high throughput BPA screening.
High Performance Liquid Chromatography (HPLC) with SPE
At Knauer, our technical team exploits a wide range of liquid chromatography systems to meet the broadest possible range of customer specifications. For the effective detection of BPA in water samples, we employ the AZURA Analytical HPLC Plus System. This comprises an AZURA P 6.1L LPG pump, an autosampler AS 6.1L, an AZURA CT 2.1 column thermostat, a AZURA MWD 2.1L multi wavelength detector and an assistant AZURA ASM 2.2L equipped with a 12 port multi position valve, a 6 port/2 position injection valve and a pump with 10 mL pump head, we believe this to be the most comprehensive system for BPA screening.
The multi-stage SPE process consists of column conditioning with columns filled with our patented KNAUER Eurospher II 100-3 C18A silica, sample extraction and sample analysis.
If you would like to learn more, refer to our application note on Sensitive Online SPE Determination of Bisphenol A in Water Samples
To get a more comprehensive idea of our collection of chromatography apparatus, get in contact today to speak to our design experts.
Automated sample pre-purification by solid-phase extraction with HPLC coupling. The use of online solid phase extraction (SPE) coupling avoids time consuming and manual sample preparation steps, making the method well-suited for routine analyses of BPA in low concentration samples like drinking water.
Advantages of Online SPE: on-line SPE technique offers increased sensitivity with reduced sample handling as all the extracted components can easily be introduced to the analytical column.
Goals of preparative Online SPE:
Resveratrol is a natural stilbene present in wine and grapes. It has been studied mainly for its antiinflammatory and anticancer activities. Flavonoids are a group of phytonutrients found in almost all fruits and vegetables and are powerful antioxidants with anti-inflammatory and immune system benefits.
Based on a sulfonated cross-linked styrenedivinylbenzene copolymer, the ionic forms Pb and Ca are best suited for the analysis of smaller carbohydrates line mono- and disaccharides and sugars up to DP 4.
Biogenic amines can have negative impacts on consumer health, as well as the wine´s sensory attributes. Elevated levels of biogenic amines typically cause a reduction in wine aroma. Therefore, the concentration and composition of these compounds must be monitored.
Flavonoids are a group of phytonutrients found in almost all fruits and vegetables and are responsible for the vivid colours. Like other phytonutrients, flavonoids are powerful antioxidants with anti-inflammatory and immune system benefits.
In the last years isotonic beverages have become more and more popular. Almost every drink is available in an isotonic version. But what does isotonic mean and what are its benefits? How can be checked that beverages are really isotonic? And have you ever heard of osmolality?
Citrus fruits contain a variety of flavonoids, including flavorless Hesperidine and bitter Naringine. Hesperidine is found in high concentrations in the fruit peel of oranges and mandarines and in substantially lower concentrations in the juice of these fruits. Naringine is also found to be similarly distributed in oranges and grapefruits.
Soft drinks sweeteners and preservatives are polar molecules which can cause problems in extraction-methods. Therefore, a method that uses minimal sample preparation is needed.
The deleterious and mutagenic mould fungus product patulin can frame during wrong cidermaking process of fruits like apple. The permitted daily exposure for patulin is regulated by the scientific committee for foodstuffs of the European commission. The specified determination routines have to be performed with HPLC according to official guidelines.