Biolab Equipment

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Introduction[edit | edit source]

Equipment for use in a biolab varies by the intended lab function. A microbiology lab will require at minimum an incubator, a sterile working area, and a pressure cooker for sterilisation. Ideally it would also have a centrifuge and appropriate glassware such as petri dishes and test tubes. A molecular biology (DNA/Protein) lab will require more equipment to handle, visualise and store DNA/Protein. A plant tissue culture lab would resemble a microbiology lab but would have artificial lighting installed in growth chambers.

Here are some examples of easily acquired/made items of equipment for a biotech lab, divided loosely by function. As many labs will require a baseline microbiology setup to function (for example, a DNA manipulation lab will require microbes to carry and safely store DNA), assume that a microbiology lab is the "minimum" lab.

Microbiology Lab[edit | edit source]

A lab that enables the safe growth, storage and handling of microbes, whether bacteria, yeast or other fungi, or single-celled algae, is a microbiology lab. Requirements include sterility, incubation, safe handling/storage, and safe disposal where relevant.

Functions of a microbiology lab include medical diagnostics by traditional culture of blood or skin samples, propagation of agriculturally important strains and species, scale-up of useful strains for fermentation or composting, nutritional fermentation of yeasts and bacteria for consumption, or as a foundation for molecular biology methods like DNA manipulation.

Incubation[edit | edit source]

An incubator can be produced using a simple thermostat and a heater, and a well-insulated compartment or container. A simple example is a polystyrene shipping box with a radiative infrared heating mat and a pet thermostat, which can easily and accurately maintain a 30C incubator.

Sterilisation[edit | edit source]

A pressure cooker can be used to sterilise heat-stable liquids, solids and equipment by maintaining full temperature and pressure for 20-25 minutes. To confirm sterilisation, chemical indicator tape that changes colour is normally used, although cultures of heat-stable spores could also be used as indicators; after sterilisation, the indicator culture is incubated and observed for growth, which would indicate a failed sterilisation. The usual spore culture used for this is Bacillus stearothermophilis though B.subtilis (below) spores would probably suffice.

For heat-stable equipment, wrapping in metal foil and baking at 200C for 1:20 hours is sufficient. Longer time periods at lower temperatures can be used also if 200C is beyond the reach of available equipment.

Where filters are available, filter sterilisation is an attractive means of sterilising heat-labile liquids such as antibiotic samples. Filters may consist of "candle" filters used for water sterilisation (although the strict requirements of a lab may call for double-filtration), or syringe-powered filter cartridges. It is possible (though never tested) that in-house-produced cellulose filters from kombucha could be used if properly treated and if suitable pressure is applied.

Finally, for heat-labile ingredients, tyndallisation can be used; over three successive days, steam is used to pasteurise the sample. Vegetative (growing) bacterial/yeast/fungal cells are killed during the steaming process, and as new cells germinate over the following two days they are also killed. This process is somewhat gentler than pressure cooking, but more labour intensive and prone to failure.

Centrifugation[edit | edit source]

A centrifuge is used to separate cells from a liquid culture, and for transferring cells from one culture sample to another, possibly with "rinsing" steps. The procedure is simple; cells are spun at a high speed so that they are pelleted against the bottom of the sample vial/tube, and the liquid they were suspended in can then be removed with a pipette. The pelleted cells can then be resuspended in a new liquid using agitation with a pipette or inverting/vortexing/flicking/spinning the tube.

DremelFuge is a 3D printed centrifuge rotor that can be fitted to a Dremel multitool or a drill, and is Open Source Hardware.

Blenderfuge is a centrifuge produced by drilling out a rotor for use on a domestic blender appliance or similar.

Sterile Working Area[edit | edit source]

A HEPA filter, perhaps repurposed from an automotive or vacuum cleaner or as part of a room air purifier, can be used to direct a sterile airflow onto a surface, providing a sterile working area. Within this area, sterilised samples will likely remain sterile with proper lab methods on the part of the operator.

A bunsen burner or camping burner with a strong blue flame can produce an area of effective sterility, both by cycling air that has been through the flame and by providing a local updraft that prevents downward contamination upon samples and petri dishes.

Cultures[edit | edit source]

Essential to a microbiology lab are microbes to be grown within. These could be native or wild species cultivated for study or development, medical samples (handle with care), or laboratory cultures provided by another lab. Laboratory strains deserve special note:

E.coli is the prototypical bacterium, and is the "model organism" of modern bioscience. Contrary to its bad reputation, most strains of E.coli are relatively harmless and can probably be found living quietly inside most mammals. E.coli lab strains are mostly derived from a lab strain called E.coli K12, and are generally too incompetent to survive in the wild (or the gut, for that matter).

Lab strains of E.coli are used in most labs to carry DNA constructs called Vectors, which usually refers to circular DNA molecules called Plasmids. It is as part of these plasmids that most transgenic systems are delivered into E.coli to be read from and processed, or as intermediate constructs on the way to being developed fully in another species. Because E.coli can be forced to stably maintain plasmids within the cell at high copy-numbers of plasmids per cell using antibiotics and encoded antibiotic resistance genes, it has been the main method of choice for storing DNA between uses.

However, the requirement for antibiotics in this use-case renders the use of such antibiotic-resistant plasmids unsuitable for community use; antibiotics are firstly too important to be squandered in this manner, and secondly are too expensive or difficult to produce locally for this purpose. Also, E.coli generally requires refrigeration at very low temperatures to remain stable, typically -80C in an institutional or commercial biolab. To meet this requirement in a community lab would require far too great an expense using a scale of engineering that is far from resilient.

B.subtilis is another model bacterium used in biotechnology and bioscience, though to a much lesser extent than E.coli. B.subtilis offers significant advantages for community use in terms of ease of culture, handling and storage, and there are no known hazardous strains of B.subtilis (although it has some bad relatives that are easily mistaken for it: Anthrax and B.cereus numbering among them).

Because B.subtilis forms stable spores upon starvation, it does not require refrigeration. Delivery of plasmid DNA to B.subtilis is, in principal, easier than with E.coli because B.subtilis has a natural tendency to adopt and use compatible DNA present in the environment (i.e. it can genetically manipulate itself when conditions are suitable). However, the prevailing method of industrial manipulation also employs antibiotic selection. Alternatives could be developed that do not require antibiotic resistance.

B.subtilis has not been as popular as a carrier for DNA because of perceived DNA stability issues; however, it is possible that these stability issues could be sidestepped by mindful design of DNA to omit sites that the B.subtilis topoisomerase recognises.

The primary lab strains of B.subtilis are derived from B.subtilis 168 which, like E.coli K12, are highly domesticated and are generally considered inviable outside the laboratory environment.

Molecular Biology[edit | edit source]

In addition to the centrifuge, described above, other staples of a molecular biology lab include a thermal cycler and an electrophoresis apparatus. The thermal cycler allows for making many copies of a sequence of DNA via a process called PCR or polymerase chain reaction. The function of the thermal cycler is essentially to undergo repeated cycles of heating and cooling to facilitate chemical reactions that take place at different temperatures. The basic elements of a thermal cycler are: a heating element, a device for cooling, one or more temperature sensors, and a microcontroller to handle all these functions. Instructions are readily available for the assembly and operation of a thermal cycler, and there are also open source hardware options such as OpenPCR.

Electrophoresis is the process of separating molecules based on size and charge by applying current and observing the rate and direction at which they move through a semi-solid medium such as agarose gel. Negatively charged molecules move towards the positive electrode and visa versa. Larger molecules move more slowly through the medium than smaller fragments. An electrophoresis apparatus is essentially a chamber, typically made of transparent plastic, with a cathode at one end and an anode at the other. A power supply is also needed to apply current to the electrodes. A variety of materials will work for the anode, but platinum is generally required for the cathode. Additionally, a casting mould is typically utilized to pour the gel, and a comb creates wells in the gel where the material being analyzed can be inserted. Many of these components can be 3D printed, and stl files can be found on Thingiverse. This section needs work.

Plant Tissue Culture[edit | edit source]

This section needs work.

Animal Tissue Culture[edit | edit source]

This section presents a potential health hazard and should be carefully considered. It also needs work.