3-D Printing for a PET Radiochemistry Operation

1046 Objectives: A PET Radiochemistry Facility is faced with the need to have unique objects designed, fabricated and modified. Utilizing outside sources to achieve these objectives can be time consuming, expensive and often-times are not available. Additionally, capability to prototype offers an in-house engineering pathway for design which contributes toward efficient and effective workflows within a PET radiochemistry environment. A low cost and effective solution to this challenge is offered by the development of 3-D printing technology. METHOD: A 3D printer was required that offered, i) cost effectiveness, ii) reliability, iii) a small footprint and iv) versatility with options for expansion. The Desktop TAZ 6 (LulzBot, Loveland CO) was selected as the printer which would best meet our criteria. 3D printing uses thermoplastic feedstock (filament) in a process known as Fused Deposition Modeling (FDM) which is an additive manufacturing (AM) technology used for design, prototyping, and production applications. In the AM model, FDM works by building layers of filament material. PET radiochemistry processes are exposed to a broad spectrum of conditions including, varying strength of radiation field, a range of chemical conditions and a selection of mechanical stress environments. Availability of different filaments enhances the capability of printed materials to withstand these conditions. The specifications for the two most common filaments used in our practice, are listed in the accompanying table. Utilizing water soluble filaments allows design and build of more complex intricate objects by use of a dual head extruder. One head extrudes insoluble primary filament and the secondary head prints a water soluble support filament. The build process requires several steps. First, design of an object using a software design package typically purchased independently from the 3-D Printer package. Second, the finished design is exported to the 3-D printer computer control software program which prepares the object for printing. RESULTS: We have been able to 3D print objects which achieve or exceed expectations. We have increased efficiency and reliability of our practice. Two simple design/fabrication examples i) clamps to secure columns of multiple solid phase extraction purification cartridges and ii) a solid target transport system carrier used to move an irradiated solid target foil from cyclotron vault to hot cell. Other projects include, vial shield spacers, syringe holders for dose calibrator dippers, sterile vial holders, pill holder and many others. All have been produced as original designs or a modification to an existing design. CONCLUSIONS: Many elements contribute to a successful PET radiochemistry practice. One of these is optimization of workflow by inclusion of an option for independent in-house design and fabrication of objects that increase efficiency and effectiveness of processes or systems. In its most basic form, 3-D printing is a relatively fast, accessible and cost effective tool. It assists the problem solving process by offering an in-house platform to design and fabricate both simple and relatively complex objects. In practice, there are limitations; for example, filament materials may not offer sufficient mechanical strength for the intended use. This said, greater than thirty filament types are available for the 3-D printer used at Mayo Clinic Rochester. Nevertheless, any drawback is far outweighed by the positive contribution the technology has added to our practice.