Living cells have spontaneous ultraweak photon emission derived from metabolic reactions
associated with physiological conditions. The ORCA-Quest CMOS camera (Hamamatsu Photonics,
Japan) is a highly sensitive and essential tool for photon detection; its use with
a microscope incubator (Olympus) enables the detection of photons emitted by embryos
with the exclusion of harmful visible light. With the application of the second law
of thermodynamics, the low-entropy energy absorbed and used by embryos can be distinguished
from the higher-entropy energy released and detectable in their environment. To evaluate
higher-entropy energy data from embryos, we developed a unique algorithm for the calculation
of the entropy-weighted spectral fractal dimension, which demonstrates the self-similar
structure of the energy (photons) released by embryos. Analyses based on this structure
enabled the distinction of living and degenerated mouse embryos, and of frozen and
fresh embryos and the background. This novel detection of ultra-weak photon emission
from mouse embryos can provide the basis for the development of a photon emission
embryo control system. The ultraweak photon emission fingerprints of embryos may be
used for the selection of viable specimens in an ideal dark environment.
