Comparison of speed-vacuum method and heat-drying method to measure brain water content of small brain samples

6533b870fe1ef96bd12d055c

RESEARCH PRODUCT

Comparison of speed-vacuum method and heat-drying method to measure brain water content of small brain samples

Tobias Hirnet Serge C. Thal Anne Sebastiani Antje Jahn-eimermacher

subject

Male 0301 basic medicine Hot Temperature Time Factors Genotyping Techniques Vacuum Neuroscience(all)Analytical chemistry Small brain Brain Edema Centrifugation Brain water 03 medical and health sciences 0302 clinical medicine Brain Injuries Traumatic Animals Desiccation Water content Brain Chemistry Moisture Chemistry Brain edema General Neuroscience technology industry and agriculture Area under the curve Water Mice Inbred C57BL Disease Models Animal Boiling point Neuroprotective Agents Sodium Bicarbonate 030104 developmental biology ROC Curve Area Under Curve Content (measure theory)Feasibility Studies 030217 neurology & neurosurgery Biomedical engineering

description

Abstract Background A reliable measurement of brain water content (wet-to-dry ratio) is an important prerequisite for conducting research on mechanisms of brain edema formation. The conventionally used oven-drying method suffers from several limitations, especially in small samples. A technically demanding and time-consuming alternative is freeze-drying. New method Centrifugal vacuum concentrators (e.g. SpeedVac/speed-vacuum drying) are a combination of vacuum-drying and centrifugation, used to reduce the boiling temperature. These concentrators have the key advantages of improving the freeze-drying speed and maintaining the integrity of dried samples, thus, allowing e.g. DNA analyses. In the present study, we compared the heat-oven with speed-vacuum technique with regard to efficacy to remove moisture from water and brain samples and their effectiveness to distinguish treatment paradigms after experimental traumatic brain injury (TBI) caused by controlled cortical impact (CCI). Results Both techniques effectively removed water, the oven technique taking 24 h and vacuum-drying taking 48 h. Vacuum-drying showed lower variations in small samples (30–45 mg) and was suitable for genomic analysis as exemplified by sex genotyping. The effect of sodium bicarbonate (NaBic8.4%) on brain edema formation after CCI was investigated in small samples (2 × 1 mm). Only vacuum-drying showed low variation and significant improvement under NaBic8.4% treatment. Comparison with an existing method The receiver operating curves (ROC) analysis demonstrated that vacuum-drying (area under the curve (AUC):0.867-0.967) was superior to the conventional heat-drying method (AUC:0.367-0.567). Conclusions The vacuum method is superior in terms of quantifying water content in small samples. In addition, vacuum-dried samples can also be used for subsequent analyses, e.g., PCR analysis.

year	journal	country	edition	language
2016-06-07	Journal of Neuroscience Methods

10.1016/j.jneumeth.2016.11.012 http://dx.doi.org/10.1016/j.jneumeth.2016.11.012