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Every year, an unacceptably large number of infant deaths occur in developing nations, with premature birth and asphyxia being two of the leading causes. A well-regulated thermal environment is critical for neonatal survival. Advanced incubators currently exist, but they are far too expensive to meet the needs of developing nations. We are developing a thermodynamically advanced low-cost incubator suitable for operation in a low-resource environment. Our design features three innovations: (1) a disposable baby chamber to reduce infant mortality due to nosocomial infections, (2) a passive cooling mechanism using low-cost heat pipes and evaporative cooling from locally found clay pots, and (3) insulated panels and a thermal bank consisting of water that effectively preserve and store heat. We developed a prototype incubator and visited and presented our design to our partnership hospital site in Mysore, India. After obtaining feedback, we have determined realistic, nontrivial design requirements and constraints in order to develop a new prototype incubator for clinical trials in hospitals in India.

Contamination detection often requires lengthy culturing steps to detect low-level bioburden. To increase the rate of detection and decrease the limit of detection (LOD), a system featuring microfluidics and a multichannel fluorometer has been developed. The eight-channel fluorometer enables parallel testing of multiple samples with the LOD as low as <1 cfu/mL. This low-cost system utilizes the slope of fluorescence intensity that serves as the criterion for bioburden detection. The redox indicator dye resazurin is used to monitor the presence of viable cells in this study and is reduced to resorufin with a high quantum yield at 585 nm. The sample under investigation is spiked with resazurin and loaded in a special-design microfluidic cassette, and the rate of change is observed via the fluorometer. The method was validated using primary Escherichia coliculture in comparison with a spectrophotometer which served as the gold standard. An optimized assay based on Luria–Bertani medium was developed. The impact on the assay sensitivity based on incubation and filtration steps was also explored. The assay is shown to pick up inadvertent contamination from test tubes and pipette tips showing its applicability in real-world settings. The data analysis demonstrated a comparable performance of the multichannel fluorometer vis-a-vis the conventional plate reader. The multichannel system is shown to detect bioburden presence in as low as 20 s for bacterial concentrations ≥5 cfu/mL after 6 h of incubation. Considering its portability, low cost, simplicity of operation, and relevant assay sensitivity, the system is well positioned to detect low-level bioburden in the laboratory, pharmaceutical, and field settings.