Introduction: In a supported liquid membrane (SLM) extraction, also named pertraction, target analytes are extracted
from an aqueous feed sample, the ‘donor phase’, into an organic phase entrapped in micropores of a
hydrophobic support membrane, and further transferred into an acceptor phase. Different approaches and
applications of SLM extraction are described in scientific literature such as analysis of drugs, pesticides, metal
ions, organic pollutants1 etc. Though a number of SLM extraction investigations on metal ion separation have
been reported in literature2, very little work has been doneon the application of membrane extraction for
radionuclide separation3,4.
Radiopharmaceuticals are drugs labeled with radionuclide which are used in various diagnostic and
therapeutic applications in nuclear medicine. The interest for the usage of radiolabeled peptides and monoclonal
antibodies for therapy is growing in the last decade. Also, radioactive isotope 177Lu and labeled
radiopharmaceuticals are being increasingly used as therapeutic agents in nuclear medicine5. Although the
percentage of binding the radionuclide to a target molecule is usually very high (~ 98%), there is always a
fraction of the free radionuclide. This is very important in the case of radiopharmaceutical for radiotherapy. The
single dose for radiotherapy can be very high (up to 30 GBq), thus the absolute amount of free radionuclide can
be significant. The free 177Lu(III) accumulates in bones, thus is very important to separate free 177Lu(III) from
the labeled compound. The most commonly applied technique for this purification is chromatography. Except
that, the application of SLM extraction with flat membrane for separation labeled compound and free 177Lu(III)
was proposed and studied in our previous paper4.
Recently, SLM extraction has been simplified by introduction of a SLM extraction in a single hollow
fiber without any special device6. The SLM extraction in a single hollow fibre can be operated only in a batch
mode without any phase flow rate. Apart from common characteristics of membrane extraction such as large
interfacial areas, low consumption of organic solution, good opportunity for process automation etc, SLM in a
single hollow fibre has additional advantages such as easy to handle equipment, no special device to avoid
accidental release of radioactive material and a sample volume as low as 1 cm3.
The aim of the present study was to investigate the pertraction of Lu(III) from an aqueous phase by
applying miniaturized SLM extraction in a single hollow fibre. The influence of the donor pH, content of the
carrier in the organic phase and the time of extraction on lutetium extraction and stripping were investigated
