TY - JOUR
T1 - Measuring free radicals with relaxometry
T2 - Pioneering steps for measurements in human semen
AU - Li, Hui Ting
AU - Schirhagl, Romana
AU - Eliveld, Jitske
AU - Reyes-San-Martin, Claudia
AU - Pronk, Ines
AU - Hoek, Annemieke
AU - Cantineau, Astrid E. P.
AU - Mzyk, Aldona
N1 - Funding Information: The authors would like to express their gratitude towards the laboratory analysists of the Centre of Reproductive Medicine of the University Medical Centre Groningen. A.M. acknowledges and XS grant from NWO (NWO XS grant: Together in health and disease - revealing the cross-talk between semen microbiota and sperm cells). Publisher Copyright: © 2023 The Authors
PY - 2023/12/1
Y1 - 2023/12/1
N2 - A possible biological mechanism for unexplained male infertility is due to the effect of oxidative stress (OS), defined by the imbalance of reactive oxygen species (ROS) production, and the capacity of the antioxidant defence system to counteract it. In physiological concentrations, ROS and especially free radicals play an essential role in sperm maturation and fertilization, while an overabundance could lead to OS-induced damage to spermatozoa. To date, there are no direct detection techniques available that can measure the total amount of free radicals real time and identify where and when free radicals are generated. This study applies a quantum sensing technique using fluorescent nanodiamonds (FNDs), called T1 relaxometry, which is uniquely sensitive and specific for free radicals allowing measurements of the current radical load for nanoscale detection in living cells and body fluids. This proof-of-principle study investigates if we can use this technique to detect the free radical generation in human whole and separated, using density gradient centrifugation, semen. This method could be potentially used as new diagnostic measure for unexplained infertility or to track the effect of therapeutic interventions such as lifestyle changes. We adapted the existing relaxometry technique to measure free radicals in semen. The measured relaxation time (T1 time) was correlated to sperm concentration and progressive motility. Additionally, we explored the influence of the oxidative trigger hydrogen peroxide and the antioxidant glutathione on the free radical concentration measured. No significant correlations were found, which indicates that measurements in more proximity of the sperm cell are required to use relaxometry as a potential diagnostic tool for unexplained male infertility.
AB - A possible biological mechanism for unexplained male infertility is due to the effect of oxidative stress (OS), defined by the imbalance of reactive oxygen species (ROS) production, and the capacity of the antioxidant defence system to counteract it. In physiological concentrations, ROS and especially free radicals play an essential role in sperm maturation and fertilization, while an overabundance could lead to OS-induced damage to spermatozoa. To date, there are no direct detection techniques available that can measure the total amount of free radicals real time and identify where and when free radicals are generated. This study applies a quantum sensing technique using fluorescent nanodiamonds (FNDs), called T1 relaxometry, which is uniquely sensitive and specific for free radicals allowing measurements of the current radical load for nanoscale detection in living cells and body fluids. This proof-of-principle study investigates if we can use this technique to detect the free radical generation in human whole and separated, using density gradient centrifugation, semen. This method could be potentially used as new diagnostic measure for unexplained infertility or to track the effect of therapeutic interventions such as lifestyle changes. We adapted the existing relaxometry technique to measure free radicals in semen. The measured relaxation time (T1 time) was correlated to sperm concentration and progressive motility. Additionally, we explored the influence of the oxidative trigger hydrogen peroxide and the antioxidant glutathione on the free radical concentration measured. No significant correlations were found, which indicates that measurements in more proximity of the sperm cell are required to use relaxometry as a potential diagnostic tool for unexplained male infertility.
KW - Diamond magnetometry
KW - Fluorescent nanodiamond
KW - Free radicals
KW - Human semen
KW - Oxidative stress
KW - Relaxometry
UR - http://www.scopus.com/inward/record.url?scp=85172897171&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.diamond.2023.110388
DO - https://doi.org/10.1016/j.diamond.2023.110388
M3 - Article
SN - 0925-9635
VL - 140
JO - Diamond and related materials
JF - Diamond and related materials
M1 - 110388
ER -