The information of L-cysteine levels and dose-response of NAC treatment will be important in the translation of our findings to clinical setting. Despite reduced mortality has been seen in the resuscitation of asphyxiated term neonates with room air, compared to those with 100% oxygen, neonatal resuscitation with 100% Wortmannin oxygen remains a common practice in many centers, especially in community hospitals before the arrival of transport team. Recently, the guideline on the use of supplementary oxygen during neonatal resuscitation has been revised and it is recommended to start with 21% oxygen. The cardiac protective effects of NAC when 21% oxygen is used during resuscitation will be interesting. Finally, it is interesting to further examine the role of anti-oxidants during neonatal resuscitation while we studied a state of excessive oxidative stress and its related injury, which is not uncommon in clinical conditions including uncontrolled hyperoxic resuscitation of asphyxiated neonates, cardio-pulmonary bypass and veno-arterial extracorporeal membrane oxygenation. This sensitivity reduces the applicability of the enzymes in biotechnological hydrogen production schemes, for which they are otherwise very promising. Narrowing the gas channels may prevent oxygen from diffusing to the active site, but finding mutations that accomplish this is a difficult challenge. The failure of previous attempts at evolving oxygen tolerance suggests that multiple synergistic mutations may be required before any improvement is observed. In vitro compartmentalization is a technology with the potential to enable high-throughput screening of hydrogenase mutants. In IVC, extremely small aqueous droplets suspended in a continuous oil phase isolate individual mutant DNA molecules, forming independent emulsion cell-free protein synthesis reactors. Analogous to cells in an in vivo screen, the droplets co-localize the gene, the mutant protein it encodes, and the products of the desired enzymatic activity. Like other in vitro methods such as ribosome display and mRNA display, IVC can accommodate very large mutant libraries and is free of the biases inherent in in vivo platforms. However, IVC is unique among high-throughput in vitro methods in its ability to screen for multiple-turnover catalytic activity. Droplet-based technology is advancing rapidly as its potential for evaluating mutants, determining the effects of drug candidates on individual encapsulated cells, and accelerating DNA sequencing becomes apparent. Combining IVC with microfluidic technology allows monodisperse emulsion droplets to be formed, mixed, split, merged, incubated, thermocycled, ordered, assayed for fluorescence, and sorted, all within the confines of a small chip. Depending on the target of the directed evolution project, IVC can be configured as a selection or as a high-throughput screen in which fluorescence-activated cell sorting is used to analyze and sort microbeads or water-in-oil-in-water double emulsion.