Every frugal biofoundry definitely needs frugal hardware. The cost of hardware has been a huge
challenge to most biofounries. Being able to have access to open frugal hardware designs will go a
long way to increase the quality of research being conducted. As part of the friendzymes initiative,
we seek to create biofoundries across several countries where we will design and build several
hardware components to facilitate and improve the quality of the enzyme manufacturing.
We have three hardware components that are essential for frugal enzyme manufacturing, purification,
and quantification. We explain in detail the construction and outcomes of these frugal hardware we
are building to add to our biofoundries.
Frugal bioreactor
Necessary for producing the vessels of our enzymes, B. subtilis, in large amounts for them to
secrete our polymerases in large amounts.
Frugal Chromatography column
Necessary for separating desired proteins of interest after our vessels have successfully
expressed and secreted them.
Frugal Fluorescent Plate Reader
Necessary for having a readout on the purity of the enzymes obtained through our chromatography
column.
In every laboratory activity, you need hardware, gadgets, materials, and support equipment. In this
section, we give you an overview of our progress in the area of hardware and tool development. We
will go through some important steps to build, test and evaluate the three basic hardware we will be
building for our biofoundry. Building these hardware will not on;y facilitate and improve the
quality of research but will overall help save massively on the cost of acquiring commercial
hardware or constantly purchasing reagents supplies from commercial sources. In developing
countries, where access to a constant supply of reagents is a major problem, these hardware
components will help eliminate this challenge. The overall total cost in building these hardware is
approximately $4,000, which is several thousands of dollars less than commercial hardwares of the
same design. In terms of performance, these frugal hardwares are comparable to their commercial
counterparts.
Friendzymes's Frugal Bioreactors
Bioreactors play a key role in the production of proteins and enzymes for the development and global
deployment of biotechnology. These consist of vessels where a biological reaction or change takes
place. The biological systems involved can be enzymes, proteins, and microorganisms. By providing a
favorable growth environment, bioreactors meet the needs of the biological system involved so that a
high production yield is achieved.
For the design of a bioreactor, it is necessary to control the operating parameters that favor cell
growth and metabolism of cells or enzymes. The main parameters are dissolved oxygen concentration,
pH, temperature, and mixing. Commercial solutions priced between $580 to approximately $4,500 for
5-litre capacities are expensive for low-resource labs and do not allow for customization and
maintenance. The development of low-cost, open-source bioreactors could help develop a more
accessible biotechnological infrastructure that reduces financial barriers to the development of
future bioengineers.
The Friendzymes Open Science Global team seeks to accelerate the deployment of hardware needed to
democratize biotechnology worldwide through the development of two bioreactor builds made with
accessible materials, open-source, automatic controls, and a low cost of USD 82 - 162 dollars.
References
[1] Shang-Tian Yang, Chapter 1 - Bioprocessing from Biotechnology to Biorefinery, Editor(s): Shang-Tian Yang, Bioprocessing for Value-Added Products from Renewable Resources, Elsevier, 2007, Pages 1-24, ISBN 9780444521149, https://doi.org/10.1016/B978-044452114-9/50002-5.
Friendzymes Bioreactor Prototype 1.0
Design and Assembly
The design of the proposed bioreactor is of the batch type. It consists of three main parts: A)
Container and thermal insulation jacket , B) sensors and actuators and C) Electronic control system.
The materials needed to build it are:
A 4-liter glass container was selected because it is a product that is easily accessible, very inexpensive, and is fully autoclavable. The lid can be made of metal or plastic, four holes will be made through which the heater, temperature sensor and two air hoses enter. The lid can be adapted to anyone of similar size.
To prevent the heat transfer and the temperature loss through the glass walls of the container, a ceramic fiber insulating blanket is used. This blanket is placed around the container to improve the temperature control efficiency of the biological system.
b) Sensors and Actuators
An aquarium air pump was used to oxygenate the culture in the bioreactor, which is an essential component of every bacterial culture. The air pump allows adequate aeration of the culture to obtain a good oxygen transfer rate (OTR) throughout the container. The lack of oxygen in the system can affect the performance of the growing process.
The DS18B20 is a waterproof Temperature Sensor Module Kit used to measure the temperature of the system at every point in time. This is very necessary because temperature is a key component which facilitates bacteria growth. This sensor has a digital output that connects to the esp32 microcontroller. The Esp32 2.4 GHz WiFi + Bluetooth component helps us receive feedback from the sensors for modifications to be made to the system. In addition, with the implementation of esp32 Internet of Things, historical data from the temperature sensor can be accessed, from 1 day to three months.
c) Control and monitoring system
The device currently uses the Esp32 2.4 GHz WiFi + Bluetooth microcontrolador. With the PWM Pulse Width Modulation output control the voltage level is delivered to the heater and air pump. In this way it is possible to have a more precise control against external variations. Low-cost and opto device electronic components were considered to design a circuit that provides safety to the users. The two main electronic components used to achieve precise and safe control for the user were the MOC3051 optocoupler and the power device Triac BTA136. The optocoupler is a device that allows us to isolate the microcontroller control signals from the heater and air pump operating voltage through an internal light control. Thus, the external faults will not affect the control device and will keep it isolated and safe. The Triac BTA16 is a device designed for high performance, full wave alternating current general purpose applications where high noise immunity and high switching are required. Before carrying out the physical implementation of the circuit, we carried out a simulation in the LTspice software to verify the flow of currents and voltages. Then, we implement the circuit in the breadboard.
Figure 1. Schematic diagram and connections of the electronic circuit. This schematic diagram was made in the EasyEDA open software. It allows us to visualize the connection pins of each one of the devices and from there it is possible to create your own printed electronic PCB.
Future Plans
Designing an electronic circuit can lower costs when developing a product because electronic devices that fulfill a specific function are used. However, to ensure consistent and robust operation it is advisable to develop a Printed Circuit Board. It has developed the Printed Circuit Board design of our bioreactor using the EasyEDA open software. The next step will be to order the printing from a local supplier, solder the electronic components and perform the functional tests.
Test
The bioreactor was home-made and all materials were sourced from local suppliers. Due to limited access to university laboratories during COVID 19, experimental tests on bacterial culture could not yet be performed. It is planned to carry out the experimental test with Bacillus Subtilis as soon as it is possible to access the laboratories in the city. Due to this, the following tests were carried out to verify the correct operation of the bioreactor:
a) Temperature control and Remote monitoring system
Temperature control is very important to guarantee optimal growth. The bioreactor was tested to regulate at 37 ° C, showing an 0.1% error.
Figure 2. Temperature control data logging at 37ºC.
Figure 3. Remote monitoring test using Blynk software installed on a tablet.
Frugal Bioreactor Version 2 based on David Ishee’s build
At BioBlaze, we wanted to try David Ishee’s frugal bioreactor build for several reasons. First, it is huge and looks amazing. Second, the build is with inexpensive components that can be easily sourced via Amazon - only $162. Finally, there is no soldering or coding required. The most difficult thing about the build was using a flame to carefully bend a glass tube, but this was easily done using a Bunsen burner.
