Dendrimeric nanocomposites for solid phase microextraction

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Polymeric nanocomposites have demonstrated great potential as sorbents in analytical sample preparation. The polymeric domain usually provides the sorption ability while the nanometric element confers special properties (like magnetism) or improves the sorptive capacity introducing new interaction chemistries (different than those provided by the polymer) or increasing the superficial area of the nanocomposite. In a recent article published in Microchimica Acta by Prof. Bagheri and coworkers, a reference research group in this field, have outlined the use of dendrimeric nanocomposites as sorptive phases in solid-phase microextraction (SPME). Dendrimers are hyperbranched molecules with a multifunctional, homogeneous and spherical surface. They present multiple sites on the outer surface that may interact with the target analytes.

PAMAM dendrimer ethylene diamine core,
generation 0. Source: chemspider.com
Polyamidoamine (PAMAM) dendrimers can be obtained by a controlled and step-by-step approach that involves sequential Michael additions and amination steps. In this proposal, PAMAM dendrimers are obtained by the divergent method making them grow over a magnetic nanoparticle (MNP) core. To make that possible, the surface of the MNP must be previously coated with amine groups.

Once synthesized, the nanocomposite is incorporated over a stainless steel wire which acts as SPME fiber. The novel coating is applied for the headspace-SPME of selected chlorophenols from water samples with excellent results (limits of detection in the low ng per liter range). In addition, the fiber can be reused up to 60 times.

You can read the complete article, with all the specific information to synthesize this type of dendrimers, in the journal webpage.

Reference

(1) A magnetic multifunctional dendrimeric coating on a steel fiber for solid phase microextraction of chlorophenols. Link to the article

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