An innovative approach to prepare hypericin molecularly imprinted pearls using a “phyto-template”

Molecularly Imprinted Polymer Pearls Obtained by Phase Inversion for the Selective Recognition of Hypericin

“…This result arise from the fact that the AN-MAA copolymers with higher MAA content are more hydrophylic and swell in water. Hence, imprinting with pure hypericin leads to higher pore volumes (from about 88% to 92%) compared to values obtained in our previous studies [19,23].…”

“…Hence, in order to achieve the formation of tailless pearls following the phase inversion, precursor copolymers with 20 and 25% MAA were used. As seen in figure 1, the addition of pure hypericin (instead of extract [19]), in the form of a hydroalcoholic NTs extract solution, showed the same effect on the shape of the pearls, with no tails. It is worth mentioning that the imprinted pearls were rose-pink derived from the red-colored hypericin ( fig.…”

“…Properties of pearls The choice of copolymer matrices as optimum precursors for imprinting is crucial. In our previous study, we proved that both the MIP and the NIP pearls presented tails at decreasing content of MAA and of hydro-alcoholic extract extract in the feed solutions [19]. Hence, in order to achieve the formation of tailless pearls following the phase inversion, precursor copolymers with 20 and 25% MAA were used.…”

“…Recently, our group applied the wet-phase inversion method to produce MIP pearls able to selectively separate hypericin from Hypericum Perforatum L. primary extracts [18,19]. By this way, hypericin molecules can be generated from concentrated NTs extracts in situ, meaning along with the phase inversion of the copolymer.…”

“…The two series of hypericin-MIPs (H-MIPs), based on poly(AN-co-MAA) synthesized with either 20 or 25 wt.% MAA, where the template amount varied from 5 to 10 wt.% hypericin were prepared according to a previous reported wet-phase inversion method [19]. The pearls were noted hereafter MIP 20-5/ MIP 20-10 and MIP 25-5/ MIP 25-10.…”