A Purification Method of 18F-FP-(+)-DTBZ via Solid-Phase Extraction With Combined Cartridges

Background: To optimize [18F] 9-fluoropropyl-(+)-dihydrotetrabenazine (18F-FP-(+)-DTBZ) purification via solid-phase extraction (SPE) with combined cartridges to facilitate its widespread clinical application.Methods: A modified SPE purification method, employing Sep-Pak PS-2 and Sep-Pak C18 cartridges, was used for the preparation of 18F-FP-(+)-DTBZ. This method was compared to the purification method of high-pressure liquid chromatography (HPLC) and SPE with one cartridge, following quality control test and positron emission tomography (PET) imaging in healthy volunteers and patients with parkinsn's disease (PD).Results: A SPE purification method integrating Sep-Pak PS-2 and Sep-Pak C18 cartridges was implemented successfully. The retention time of 18F-FP-(+)-DTBZ purified by HPLC, SPE with Sep-Pak PS-2, SPE with Sep-Pak C18, and SPE with combined use of Sep-Pak PS-2 and Sep-Pak C18 cartridges was 8.7, 8.8, 8.7, and 8.9 min, respectively. Fewest impurity peak was detected in 18F-FP-(+)-DTBZ purified by the SPE with combined use of Sep-Pak PS-2 and Sep-Pak C18 cartridges. This modified SPE purification method provided a satisfactory radiochemical yield of 29 ± 1.8% with radiochemical purity >99% and shortened synthesis time to 27 min. The brain uptake of 18F-FP-(+)-DTBZ purified by the modified SPE was comparable to that purified by HPLC in both healthy volunteers and PD patients.Conclusions: A SPE method integrating Sep-Pak PS-2 and Sep-Pak C18 cartridges for purification of 18F-FP-(+)-DTBZ may be highly suited to automatic synthesis for routine clinical applications, as it provides excellent radiochemical purity, high yield as well as operational simplicity.

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One-Step Synthesis of N-Succinimidyl-4-[18F]Fluorobenzoate ([18F]SFB)

Molecules ◽

10.3390/molecules24193436 ◽

2019 ◽

Vol 24 (19) ◽

pp. 3436 ◽

Cited By ~ 1

Author(s):

Ida Nymann Petersen ◽

Jacob Madsen ◽

Christian Bernard Matthijs Poulie ◽

Andreas Kjær ◽

Matthias Manfred Herth

Keyword(s):

Solid Phase Extraction ◽

Total Synthesis ◽

Radiochemical Purity ◽

Solid Phase ◽

Phase Extraction ◽

One Pot ◽

Synthesis Time ◽

Synthesis Route ◽

One Step

Herein, we present a one-step labeling procedure of N-succinimidyl-4-[18F]-fluorobenzoate ([18F]SFB) starting from spirocyclic iodonium ylide precursors. Precursor syntheses succeeded via a simple one-pot, two-step synthesis sequence, in yields of approximately 25%. Subsequent 18F-nucleophilic aromatic labeling was performed, and radiochemical incorporations (RCCs) from 5–35% were observed. Purification could be carried out using HPLC and subsequent solid phase extraction. Radiochemical purity (RCP) of >95% was determined. The total synthesis time, including purification and formulation, was no longer than 60 min. In comparison to the established 3-step synthesis route of [18F]SFB, this one-step approach avoids formation of volatile radioactive side-products and simplifies automatization.

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Aspects on radiolabeling of 177Lu-DOTA-TATE: After C18 purification re-addition of ascorbic acid is required to maintain radiochemical purity

International Journal of Diagnostic Imaging ◽

10.5430/ijdi.v1n1p5 ◽

2014 ◽

Vol 1 (1) ◽

pp. 5 ◽

Cited By ~ 2

Author(s):

Stephan Maus ◽

Erik De Blois ◽

Stephan J. Ament ◽

Mathias Schreckenberger ◽

Wouter A. P. Breeman

Keyword(s):

Ascorbic Acid ◽

Solid Phase Extraction ◽

Radiochemical Purity ◽

Solid Phase ◽

Phase Extraction ◽

Injection Solution ◽

Gentisic Acid ◽

Radiolabeled Peptides ◽

The Impact ◽

Spe Purification

Purpose: Radiolabeled peptides like 177Lu-DOTA-TATE are vulnerable to radiolysis, which results in decreasedradiochemical purity (RCP) of these radiopeptides. Gentisic acid (GA) and ascorbic acid (AA) are well known ingredientsto reduce the effects of radiolysis. Currently, there is a trend to change the procedure from a manual to a cassette-basedautomated labeling and to introduce a C18 solid phase extraction (SPE) post-radiolabeling in order to removenon-incorporated 177Lu from the injection solution. However, with the introduction of SPE purification, GA and AAmight effectively be removed from injection solution with a concordant dramatically drop of the RCP. Therefore weinvestigated the impact of tC18 SPE purification on the RCP of 177Lu-DOTA-TATE.Methods: We compared the manual radiolabeling procedure with the cassette-based automated radiolabeling procedurewith/out tC18 SPE purification cartridge. The effect of tC18 purification on RCP of 177Lu-DOTA-TATE wasinvestigated by HPLC as function of the post-radiolabeling time and the concentration of activity.Results: After tC18 SPE purification, GA and AA were effectively removed and resulted in volume-dependent decreasein RCP, e.g. <95% after 5h in 20 mL. Re-addition of AA directly after tC18 SPE purification resulted in a RCP ≥95% at72h. In addition, with the cassette-based automated radiolabeling procedure we also found 28% of the original activityremaining in the activity-containing vial and tubing vs. < 1% with the manual procedure.Conclusion: Re-addition of AA post tC18 SPE purification is required to maintain RCP of 177Lu-DOTA-TATE.

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A Correlation Study between Polycyclic Aromatic Hydrocarbons in Urumqi Snow and the Surrounding Environment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.864-867.1364 ◽

2013 ◽

Vol 864-867 ◽

pp. 1364-1368

Author(s):

Yakup Parida ◽

Eslamjan Diwani

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Solid Phase Extraction ◽

Aromatic Hydrocarbons ◽

Solid Phase ◽

Total Concentration ◽

Correlation Study ◽

Phase Extraction ◽

Purification Method ◽

Surrounding Environment ◽

Polycyclic Aromatic

Based on the principle of solid phase extraction and the purification method using Florida silica, sixteen various kinds of polycyclic aromatic hydrocarbons such as naphthalene, acenaphthene and fluorene were measured in Urumqi snow by means of HPLC. The results showed that the concentration of PAHs was different in different sampling sites in Urumqi. The total concentration of PAHs was in the range of 0.2883 ~ 8.814 µg/mL and the content of PAHs snow was higher than that in water, which indicated that the snow was polluted by organic matters to a certain degree and the pollution was not so serious compared with the groundwater. So the snow has a certain application value for life.

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