Development and application of a labmade apparatus using open-source “arduino” hardware for the electrochemical pretreatment of boron-doped diamond electrodes

A User-Centric 3D-Printed Modular Peristaltic Pump for Microfluidic Perfusion Applications

Microfluidic organ-on-a-chip (OoC) technology has enabled studies on dynamic physiological conditions as well as being deployed in drug testing applications. A microfluidic pump is an essential component to perform perfusion cell culture in OoC devices. However, it is challenging to have a single pump that can fulfil both the customization function needed to mimic a myriad of physiological flow rates and profiles found in vivo and multiplexing requirements (i.e., low cost, small footprint) for drug testing operations. The advent of 3D printing technology and open-source programmable electronic controllers presents an opportunity to democratize the fabrication of mini-peristaltic pumps suitable for microfluidic applications at a fraction of the cost of commercial microfluidic pumps. However, existing 3D-printed peristaltic pumps have mainly focused on demonstrating the feasibility of using 3D printing to fabricate the structural components of the pump and neglected user experience and customization capability. Here, we present a user-centric programmable 3D-printed mini-peristaltic pump with a compact design and low manufacturing cost (~USD 175) suitable for perfusion OoC culture applications. The pump consists of a user-friendly, wired electronic module that controls the operation of a peristaltic pump module. The peristaltic pump module comprises an air-sealed stepper motor connected to a 3D-printed peristaltic assembly, which can withstand the high-humidity environment of a cell culture incubator. We demonstrated that this pump allows users to either program the electronic module or use different-sized tubing to deliver a wide range of flow rates and flow profiles. The pump also has multiplexing capability as it can accommodate multiple tubing. The performance and user-friendliness of this low-cost, compact pump can be easily deployed for various OoC applications.

Use of open source monitoring hardware to improve the production of MOFs: using STA-16(Ni) as a case study

Affordable and readily available microelectronics are becoming prevalent in teaching laboratories however these useful and economic tools are not used widely in either academia or industry. Herein we report how a metal organic framework (MOF) synthetic route can be optimized using an in situ monitoring apparatus designed in-house on open source hardware for under $100. We demonstrate that the MOF can be produced at atmospheric pressure, an improvement over previous reports, but also with a reduction in reaction time of 93%. This improvement in reaction time was predicted after a single experiment using the monitoring kit showing how efficiencies in the lab can be gained with very little experimental and monetary overhead while minimising the resources used.

Economic savings for scientific free and open source technology: A review

Both the free and open source software (FOSS) as well as the distributed digital manufacturing of free and open source hardware (FOSH) has shown particular promise among scientists for developing custom scientific tools. Early research found substantial economic savings for these technologies, but as the open source design paradigm has grown by orders of magnitude it is possible that the savings observed in the early work was isolated to special cases. Today there are examples of open source technology for science in the vast majority of disciplines and several resources dedicated specifically to publishing them. Do the tremendous economic savings observed earlier hold today? To answer that question, this study evaluates free and open source technologies in the two repositories compared to proprietary functionally-equivalent tools as a function of their use of Arduino-based electronics, RepRap-class 3-D printing, as well as the combination of the two. The results of the review find overwhelming evidence for a wide range of scientific tools, that open source technologies provide economic savings of 87% compared to equivalent or lesser proprietary tools. These economic savings increased slightly to 89% for those that used Arduino technology and even more to 92% for those that used RepRap-class 3-D printing. Combining both Arduino and 3-D printing the savings averaged 94% for free and open source tools over commercial equivalents. The results provide strong evidence for financial support of open source hardware and software development for the sciences. Given the overwhelming economic advantages of free and open source technologies, it appears financially responsible to divert funding of proprietary scientific tools and their development in favor of FOSH. Policies were outlined that provide nations with a template for strategically harvesting the opportunities provided by the free and open source paradigm.

Interactive control of purpose built analytical instruments with Forth on microcontrollers - A tutorial

The use of the computer language Forth for controlling experimental analytical instruments built in laboratories is described. Forth runs on a microcontroller and as it is an interpreted language the user can directly communicate with it by employing a terminal emulator program running on a personal computer. Thus the user can test attached hardware, such as pumps, valves, electronic pressure regulators, detectors and chemical sensors, directly from the keyboard. This overcomes the lack of interactivity, a significant shortcoming, of the computer languages C and C++, the default on such microcontroller platforms as the Arduinos, which have become very popular in recent years for laboratory applications. Common examples of purpose built experimental analytical laboratory instruments are sequential injection analysis systems, microfluidic devices, or automated sample extraction systems. Application examples from our laboratory are given, namely the regulation of mass-flow controllers for gases, the sequencing of an experimental capillary electrophoresis instrument and the acquisition of a signal from an alcohol sensor.