Facile assembly of an affordable miniature multicolor fluorescence microscope made of 3D-printed parts enables detection of single cells

Abstract

Fluorescence microscopy is one of the workhorses of biomedical research and laboratory diagnosis; however, their cost, size, maintenance, and fragility has prevented their adoption in developing countries or low-resource settings. Although significant advances have decreased their size, cost and accessibility, their designs and assembly remain rather complex. Here, inspired on the simple mechanism from a nut and a bolt, we report the construction of a portable fluorescence microscope that operates in bright-field mode and in three fluorescence channels: UV, green, and red. It is assembled in under 10 min from only six 3D printed parts, basic electronic components, a microcomputer (Raspberry Pi) and a camera, all of which can be readily purchased in most locations or online for US $122. The microcomputer was programmed in Python language to capture time-lapse images and videos. Resolution and illumination conditions of the microscope were characterized, and its performance was compared with a high-end fluorescence microscope in bright-field and fluorescence mode. We demonstrate that our miniature microscope can resolve and track single cells in both modes. The instructions on how to assemble the microscope are shown in a video, and the software to control it and the design files of the 3D-printed parts are freely available online. Our portable microscope is ideal in applications where space is at a premium, such as lab-on-a-chips or space missions, and can find applications in basic and clinical research, diagnostics, telemedicine and in educational settings.

The Field Guide to 3D Printing in Optical Microscopy for Life Sciences

“…The microscope parts that can be built vary with the technology and materials available. In the literature, whole microscope bodies have been printed, including the base, [20][21][22] the body, [20,22,23] holders for the filters, [22,24] objectives, [25] coverslips, [21] pin-holes, [21,23] and heat sinks. [25] Microscope chambers [26] and controller mounts [27] have also been implemented, allowing a high degree of customization to researchers adopting this technology.…”

The Field Guide to 3D Printing in Microscopy

“…The microscope parts that can be built vary with the technology and materials available. In the literature, whole microscope bodies have been printed, including the base (13,15), the body (13,15,16), holders for the filters (15,17), objectives (18), coverslips (14), pinholes (14,16) and heat sinks (18). Additionally, microscope chambers (19) and controller mounts (20) have also been implemented, allowing a high degree of customisation to researchers that adopt this technology.…”

Serial imaging of micro-agents and cancer cell spheroids in a microfluidic channel using multicolor fluorescence microscopy

“…In numerous application domains ranging from single-cell visualization to rapid diagnosis, multicolor fluorescence microscopy is recognized as a key emerging technology [11][12][13][14][15][16][17][18][19][20][21][22][23]. The working principle of this microscopy technique is based on performing imaging using spectrally-different conventional fluorescent dyes [11], endogenous fluorophores [22], fluorescent proteins [24], or quantum dots [25].…”

“…The simplest way is to collect multicolor images using a combination of an imaging sensor and single-band filters. Individual fluorescence images are collected by changing the filters with different bandwidths [ 23 , 26 , 27 ]. However, performing imaging by positioning the filters either manually or using a motorized drive creates a delay and limits the image acquisition rate.…”