Construction of a Low-cost Mobile Incubator for Field and Laboratory Use.

Incubators are essential for a range of culture-based microbial methods, such as membrane filtration followed by cultivation for assessing drinking water quality. However, commercially available incubators are often costly, difficult to transport, not flexible in terms of volume, and/or poorly adapted to local field conditions where access to electricity is unreliable. The purpose of this study was to develop an adaptable, low-cost and transportable incubator that can be constructed using readily available components. The electronic core of the incubator was first developed. These components were then tested under a range of ambient temperature conditions (3.5 °C - 39 °C) using three types of incubator shells (polystyrene foam box, hard cooler box, and cardboard box covered with a survival blanket). The electronic core showed comparable performance to a standard laboratory incubator in terms of the time required to reach the set temperature, inner temperature stability and spatial dispersion, power consumption, and microbial growth. The incubator set-ups were also effective at moderate and low ambient temperatures (between 3.5 °C and 27 °C), and at high temperatures (39 °C) when the incubator set temperature was higher. This incubator prototype is low-cost (< 300 USD) and adaptable to a variety of materials and volumes. Its demountable structure makes it easy to transport. It can be used in both established laboratories with grid power or in remote settings powered by solar energy or a car battery. It is particularly useful as an equipment option for field laboratories in areas with limited access to resources for water quality monitoring.

Novel materials enable a low-cost temperature-light gradient incubator for microbial studies.

We describe the construction of temperature-light gradient incubator with a novel material: a thermally-conductive graphite foam that is lightweight, chemically resistant, economically competitive with metal, and much cheaper to fabricate. We combined this material with a variable-intensity LED light array to construct a low-cost light-temperature gradient incubator, and demonstrate its use for studies of microbial growth, enrichment, and isolation.

Inexpensive low-oxygen incubators.

Although the evidence is overwhelming that ambient oxygen is at least somewhat damaging to most normal cells in culture, the expense and effort involved has resulted in few laboratories growing their cells under physiological oxygen conditions. We here describe how to produce, from commercially available plastic wide-mouth jars, very simple gas-tight containers that can be flushed with prepared gas mixtures to produce low-oxygen environments for standard cell culture. This permits any laboratory to easily try the effects of physiological oxygen on their system without the need for dedicated incubators and substantial monetary investments.

Simplifying assisted conception techniques to make them universally available--a view from India.

In-vitro fertilization and related assisted conception techniques are beyond the reach of most infertile couples in India because they are so expensive. Recent innovations such as the use of the natural cycle, the techniques of gamete intra-Fallopian transfer, intravaginal culture and transcervical oocyte--sperm transfer, vaginal ultrasound-guided oocyte retrieval and the availability of ready-to-use culture medium have helped to simplify assisted conception. Research today should focus on further developing these techniques so that better pregnancy rates can be achieved with them. These simplified inexpensive assisted conception techniques can then be adapted for conditions in the developing world, so that infertile patients the world over can benefit from them.