Separator nanobead-agglomerated

Carbonate-Selective Nanobead-Agglomerated Anion Exchangers At present. Thermo Fisher Scientific offers four different carbonate-selective, nanobead-agglomerated anion exchangers with diverse selectivities. The structural and technical characteristics of these separator coliunns are summarized in Table 3.6. Special columns for the separation of polyvalent anions and carbohydrates, amino acids, and oligonucleotides are also available. 

When it was introduced, lonPac AS12A was clearly the most modern nanobead-agglomerated anion exchanger for the separation of fluoride, oxyhalides, and mineral acids. The latest development in the field of universal purpose anion exchangers for water analysis is lonPac AS22. It is based on a hyper-branched polymer and discussed in Section 3.4.I.5. 

A much higher resolution between fluoride and chloride is obtained by using a CarboPac PAl-type stationary phase. Compared to nanobead-agglomerated anion exchangers such as lonPac AS4A-SC, this separator column, which was initially developed for the analysis of carbohydrates, exhibits a signiflcantly higher capacity. As a result, chloride retention increases to more than 20 min. 

Arogenic acid is not stable at acidic pH. Thus, it cannot be analyzed by cation-exchange chromatography. However, on a nanobead-agglomerated anion exchanger with alkaline eluents, the separation of this compound from the amino acids phenylalanine and tyrosine is accomplished without any problem. 

Table 3.39 Structural and technical properties of nanobead-agglomerated anion exchangers for oligonucleotide separations.

Corporation, are called nanobead-agglomerated cation exchangers. Their structure is schematically depicted in Figure 4.36. However, separator columns such as lonPac CSS and Fast-Sep Cation, which were manufactured using to this methodology, are no longer available. 

Figure 4.6S Schematic representation of the separate steps in the manufacturing of the lonPac CS5A bifunctional nanobead-agglomerated ion exchanger.

Figure 4.66 Separation of transition metals on the lonPac CS5A bifunctional nanobead-agglomerated ion exchanger. Column dimensions 250 mm x4 mm i.d. eiuent 7 mmol/L pyridine-2,6-dicarboxyiic acid -I- 66 mmol/L KOH -I- 74 mmol/L formic acid -I- 56 mmol/L K2SO4 flow rate 1.2 mL/min detection ...

Alternatively, uranyl cations can also be separated on a nanobead-agglomerated cation exchanger utilizing a buffer mixture of ammonium sulfete and sulfuric acid as an eluent Detection is performed as it is for transition metals, via derivatization with PAR. 

Figure 4.71 Separation of aluminum on a nanobead-agglomerated cation exchanger. Separator column lonPac CS3 eluent ...

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