Aminex HPX

The withdrawn hquid-phase samples were analyzed with an HPLC (Biorad Aminex HPX-87C carbohydrate coluttm. 1.2 ttiM CaS04 in deionized water was used as a mobile phase, since calcium ions improve the resolution of lactobionic acid [17]). Dissolved metals were analysed by Direct Current Plasma (DCP). The catalysts were characterized by (nitrogen adsorption BET, XPS surface analysis, SEM-EDXA, hydrogen TPD and particle size analysis). 

Tokyo, Japan) BioRad Aminex HPX-87H Sulfonated PS-DVB 9 P H+ form, exclusion 103... 

HPLC analysis for succinic acid, succinamic acid, succinamide, succinimide, N-methylsuccinimide, butyric acid, and propionic acid was performed with a Waters Model 515 HPLC pump equipped with a Waters Model 2410 Refractive Index Detector. Separations were performed with an Aminex HPX-87H 300mm column (Bio-Rad Laboratories, Hercules, CA) operated at 35°C, and using 0.005 M H2S04 elluent. 

Kiwi juice Juice filtration through 0.45 Um filter Aminex HPX 87C (30x0.78 cm) HP RI [98] ... 

Aminex HPX-87C UV210 nm 15 % acetonitrile in 0.01MHjSO4, containing 1 mM CaS04 Benzoic acid. Citric acid. Malic acid, Fumaric acid, etc. 39... 

Aminex HPX-87H UV210 nm and RID 0.002 N H2SO4 Benzoic acid. Citric acid. Gluconic acid 39... 

All reactions were run in a Parr stirred autoclave (Model 4561) at 1000 psi H2 and 200°C for 6h. A weighed quantity (0.5 g dry basis) of the catalyst, Ru/C or Ni/Re/C, was introduced into the reactor and reduced at 250 C and 200 psi H2 (Ru/C) or at 280°C and 500 psi H2 (Ni/Re/C) for 13 hours. After cooling, 100ml of solution (l.OM GO and O.l-l.OM KOH) was added to the closed reactor. For reactions in solvent mixtures, entries 1-4 in Table 2, the water/solvent ratio was 1/9 (v/v). When the solvent was either t-BuOH or 1,4-dioxane, 1.5 g of water was added to the solution to facilitate dissolution of KOH, because of its low solubility these solvents. Once steady state was achieved following heatup, samples were taken at 30 minute intervals for the first hour, and then hourly, and analyzed via HPLC. The HPLC column was a BIORAD Aminex HPX-87H run at 65 C with 5mM H2SO4 as the mobile phase at a flow rate of 0.6mFmin, using both UV (210 nm) and refractive index (RI) detection. 

Liquid chromatography (Waters, Alliance 2695 pump) is performed using an Aminex HPX-87C column (250x4.0 mm, bead size 9 pm, Bio-Rad Laboratories, Veenendaal, The Netherlands). An isocratic eluent of 40% acetonitrile/water is used, with the column kept at 65°C. The flow rate is set to 0.4 ml/min and is split after the analytical column in a ratio of 1 2, resulting in an inlet flow into the tandem mass spectrometer of 200 pl/min 20 pi of sample is injected onto the column and the total run time is 24 min. 

High-performance liquid chromatography (HPLC) system with refractive index detector and HPLC column (e.g., Aminex HPX-87H, Bio-Rad) fitted with suitable guard column... 

As stated in Basic Protocol 1, the method of HPLC used may change depending on the organic acids present in the sample. This method uses a Bio-Rad Aminex HPX-87H column for HPLC analysis. An internal standard is important for the analysis of organic acids. This provides a means of not only determining if the analysis is working but also quantitating the percent recovery of the method. 

High-performance liquid chromatograph (HPLC e.g., Waters Chromatography) equipped with column heater, solvent pump, UV detector (set at 214 nm), integrator, autosampler, and (for manual injection) 10-p.l sample loop Aminex HPX-87H column (Bio-Rad)... 

Equilibrate an Aminex HPX-87H column and guard column with mobile phase (0.005 M H2S04) for >30 min prior to the first injection. 

Provides a good description of the Aminex HPX-87H column (see Basic Protocol 2) and its applications. 

Typical applications of ion exchange in sugar analysis include (a) complexation of borates, which accentuates ionic interactions with the exchanger (27), (b) use of hydroorganic eluents, especially acetonitrile/water, with rigid, fine-particulate anion columns (28), (c) use of basic eluents, since most carbohydrates are weak acids with pKfl of 12-13 (29), (d) complexation with cations, Pb2+, Ca2+ and Ag+ being the most frequently employed, (e) the use of cation exchangers in a heavy metal form, e.g., Aminex HPX-85. 

An example of separation obtained with this method is reported in Fig. 2. Falque and Fernandez (23) study the influence of time of contact with the skins on the composition of the volatile fraction and of the carboxylic acids in wine produced from Treixadura grapes. Also, these authors quantify glycerol and ethanol, besides carboxylic acids and sugars, through the use of an Aminex HPX-87H (300 X 7.8 mm) column, but with the mobile phase of H2S04 0.65 mM at 75°C and a flow of 0.7 ml/min. They use a UV detector at 214 nm and an RI in series. The sample requires only a filtration at 0.45 /im, as described in their survey (24). 

Tartaric, malic, citric, pyruvic, succinic, lactic, acetic, shikimic, galacturonic, citramalic Wine AMINEX HPX 87H (300 X 7.8 mm) 45°C 0.0075 M h2so4 UV, 210 nm 24... 

A simple isocratic technique was developed for the quantitative analysis of OAs in dairy products. An Aminex HPX-87 (300-mm X 7.8-mm ID) analytical column was eluted with 0.009 N H2S04 mobile phase UV detection at 220 and 275 nm was utilized. Lactic, citric, formic, acetic, propionic, and butyric acids were quantified for whole milk, skim milk powder,... 

Prior to high-performance liquid chromatography (HPFC), samples were filtered through a 0.2-gm pore size mixed cellulose ester filter (Schleicher Schuell, Dassel, Germany). Buffer components such as acetic acid, citric acid, maleic acid, and succinic acid were separated on an Aminex HPX-87H (Bio-Rad, Hercules, CA) organic acid column at 65°C using a... 

The amount of mono- and disaccharides released (glucose, xylose, cellobiose, and arabinose) by pretreatment utilizing acid and enzymatic hydrolysis was analyzed by high-performance liquid chromatography (HPLC) (Shimadzu, Kyoto, Japan), using an Aminex HPX-87H column with a matching precolumn (Bio-Rad, Hercules, CA) at 65°C. The eluent was 5 mM H2S04 at a flow rate of 0.5 mL/min with detection by refractive index. 

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