Amberlite adsorption efficiency

Adsorption chromatography is an efficient way to isolate organic acids from large volumes of water. The nonionic, macroporous, Amberlite XAD-8 and the weak-base anion-exchange resin Duolite A-7 are two resins well suited for this purpose. These resins have been successfully used to extract organic acids from natural waters at sites where it was necessary to process thousands of gallons of sample. 

Results of adsorption experiments are presented in Table 2. In solution, TNF-a, a polypeptide with MW 17 kD, exists as a trimer with MW 51 kD. The monomeric units are kept together due to the hydrophobic interaction. From the experimental data it is clear that large mesopores play a relatively minor role in adsorption of TNF-a, as both MN resins adsorb it rather efficiently. Isoelectric point of TNFa is similar to that of serum albumin (pi between 4.8 and 5.6) [11], It has been shown that TNFa can be removed from biological media using non-polar cross-linked polystyrene adsorbents of the Amberlite type (XAD-2, XAD-4 and XAD-6) [12], This observation confirms that hydrophobic interactions play an important role in the adsorption of TNFa at neutral pH. Our data support this conclusion. 

It has also been demonstrated that styrene—DVB copolymer resins Sepabeads SP825, Sepabeads SP850, Optipore L-493, Diaion HP-20, and Amberlite XAD-4, of which the first three have a surface area of 1000 m /g and might be attributed to hypercrosshnked sorbents, accumulate lipophilic marine toxins okadaic acid and dinophysistoxin-1 from Prorocentrum lima cultures [298]. The procedure developed in the study represents a simple and efficient method suitable for solid-phase adsorption toxin tracking in both cultural fiquids and natural waters. The toxins are eluted from the resins with methanol and subjected to LC-MS analysis. 

Appropriate matching of the indicator to the analyte and the design of its durable and efficient immobilization procedure governs the performances of the sensor. Adsorption is one of the technique, which can be utilized for immobilization of the reagent. The chapter described a few possibilities of preparation of the optomembrane for FOCS. We have investigated immobilization properties of Amberlite resins, microporous membranes made of... 

The extraction efficiency of SIRs prepared by direct adsorption of Cyanex 272 onto amacroporous polymeric support of styrene-divinylbenzene (Amberlite XAD2) and those prepared by polymerization of styrene-divinylbenzene in the presence of Cyanex 272 (Levextrel type) were evaluated in column operations. The breakthrough curves obtained for solutions containing Zn(II), Cu(II), and Cd(II) in the low concentration range 1-100 mg/L are shown in Figure 9.16. 

---