1-12 的 799 產品與服務
1-12 的 25 Business Insights
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).
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.
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 analysis focuses on the detection of trace level semi-volatile organic compounds in extracts from solid waste matrices, soils, air sampling media and water samples. The method lists over 200 compounds however a majority of laboratories target between 60 and 90 for most analyses. The study presented here demonstrates the PerkinElmer? Clarus? SQ 8 GC/MS, not only meets the method requirements but provides users flexibility to satisfy their individual productivity demands. An extended calibration range is presented as are the advantages of the Clarifi? detector.
In today’s budget-constrained, yet highly competitive laboratory environments, the samples you’re being asked to analyze - whether food, pharmaceutical, petrochemical, or environmental - are increasingly difficult. But for some labs, having a dedicated GC for every application isn’t an option. For them, a GC that can do it all isn’t just a nice-to have, it’s a necessity.
The purpose of this study is to demonstrate the proximate analysis of two standard samples using the STA and show that the performance is easily able to allow this moderate cost, small profile and sturdy instrument to be used for this type of routine analysis.
In this work, samples were digested with aqua regia using reflux conditions according to DIN method 38414. After proper dilution of the digested sample solution, Hg was measured interference-free using SnCl2 as the reductant. The recoveries of spiked mercury in sewage sludge samples ranged from 96 to 100%. The method was checked by the analysis of standard reference materials. All results were in agreement with certified values. The RSD for three replicates was approximately 2% at 10 μg/L Hg level.
To meet the demands of complex petrochemical testing, our new Clarus? 590 and 690 gas chromatography (GC) instruments are preconfigured to provide a turnkey solution for a wide range of applications, including Simulated Distillation. We deliver a complete, ready-to-go system for faster, more efficient analysis in compliance with ASTM methods. Discover how the Clarus GC instruments enable the superior sensitivity and throughput you need for your most critical applications – plus the versatility to handle more.
Herbal lifestyle products are widely used as alternatives to medicines around the world, with as many as 80% of people using them as a primary source of healthcare in developing countries. These treatments are commonly regarded by scientific papers, and on some occasions the media, as being inferior to orthodox treatment. This is due to the variation between herbal formulations which will not be present in so called ‘single-chemical’ drugs. The reasons for the aforementioned variation involve several factors including storage, environmental conditions, handling and unintentional or intentional contamination (adulteration).
The synthesis of active pharmaceutical ingredients (API) may require multiple reaction steps that produce undesirable reaction byproducts or utilize various solvents that have to be removed from the finished product. These solvents and byproducts may be measured with headspace gas chromatography for those volatile residual organic solvents according to the USP chapter 467 method. Method USP 467 classifies residual solvents into three classes according to toxicity; class 1 solvents are to be avoided unless there is strong justification, class 2 solvents are those that should be limited due to toxicity concerns.
For laboratories analyzing everything from air quality to flavors and fragrances, thermal desorption offers a faster, easier, more cost-efficient way to prepare samples for GC or GC/MS analysis. Ideal for the trace-level measurement of volatile organic compounds (VOCs)—as well as most semi-volatile chemicals—thermal desorption lets you avoid time-consuming, manual, solvent-based sample preparation in favor of a simple, streamlined, automated approach. It also delivers the added benefits of superior throughput and enhanced sensitivity.