Methods for rapid prototyping novel labware: using CAD and desktop 3D printing in the microbiology laboratory

Abstract

Significance and Impact of the Study: We present methods for designing and 3D printing microbiological labware offering alternatives to off-the-shelf consumables that allow low-cost rapid prototyping and customisation of microbial culture tools. We demonstrate customised 3D printed rapid prototype solid medium culture dishes and dip-slides, and modified inoculating loops and customisable replicating pins for plating bacteria. 3D printed labware can offer local production to avoid dependence on commercial suppliers, rapid customisation of existing designs, and rapid evaluation of entirely new tools. Using 3D printing to develop novel labware tailored to simplify routine work in the microbiology laboratory can save time and labour compared to relying on off-the-shelf mass-manufactured labware.

PiRamid: A compact Raspberry Pi imaging box to automate small-scale time-lapse digital analysis, suitable for laboratory and field use

“…Yet in both cases, core assay equipment, multi-well plates, and Petri dishes remain identical requiring quantitation of colour changes that indicate microbial identification, in a range of different devices and conditions. Recent innovations have shown that traditional large devices can be replaced by smaller devices including custom 3D printed labware [12] down to the smallest sample volumes being assessed within microfluidic devices [13] , [14] and droplet microfluidics [15] , [16] . Flexibility and customisation are therefore vital for a lab imaging platform to be useful for as many different applications as possible.…”

“…We printed using PLA and found no problems with mechanical or optical properties in our example applications, however, we expect the design could be printed with other filaments for example with higher melting temperatures. We and others have previously shown PLA can be sterilised using 70 % Ethanol, important for some life science applications [12] , [27] . We added above the imaging stage design support for a 100 × 95 mm sheet of light-scattering white translucent acrylic to make the backlight of the imaging stage more even in brightfield mode.…”

3D-Printed Dip Slides Miniaturize Bacterial Identification and Antibiotic Susceptibility Tests Allowing Direct Mastitis Sample Analysis

“…The design of the 3D printed frame used in this study includes two parts to identify bacterial species with two 35 mm × 7 mm rectangles; and to determine MIC, we used two rows of 6 mm diameter round wells. All designed files were published as open source models for customization or 3D printing by anyone [24]. The two rows of 10× round wells include up to 10 antibiotic concentrations, which are typically prepared as doubling dilutions.…”

“…The Standard Tessellation Language (STL) design of the frame dip slide is available online [24], the frame dips slide were 3D printed, sterilized with 70% alcohol and dried before use. CHROMagar™ Mastitis (CHROMagar™, Paris, France) was prepared according to the manufacturer's instructions and added to long rectangles to identify bacterial species.…”

“…At the same time that high-performance cheap digital cameras permit smaller colonies to be detected earlier, additive manufacturing methods such as 3D printing have become inexpensive and accessible, with fused-filament deposition methods cost-effective for producing routine microbiology labware [24]. Applying 3D printing to rapid custom microbiology labware production, we designed a new frame to create dip slides that combine two main functional goals: (1) directly identify and (2) determine the antibiotic MIC of microbes from samples.…”