A Robust Chemical-free Platform for Age-Synchronized <i>Caenorhabditis elegans</i> Populations Maintenance for High-Throughput Screening in Aging Studies

<i>Caenorhabditis elegans</i> (<i>C. elegans</i>) is a well-established model for investigating the mechanisms of aging and age-related disorders like neurodegeneration. However, maintaining age-synchronized populations of <i>C. elegans</i> for aging studies without genetic or pharmacological interventions presents significant challenges, given their high reproductive rate: each nematode produces over 300 progeny. The traditional method for maintaining an age-synchronized population for multi-day studies without interventions is labor-intensive and low-throughput, hindering research on aging mechanisms and the identification of novel interventions for aging. To address these limitations, a novel, robust method was developed to sustain age-synchronized populations in a 96-well plate liquid culture format for up to 12 days without custom-made apparatuses. The robustness of this method was substantially improved by optimizing the surface composition of the multi-well plate and disposables, refining culture parameters, including life stage, medium composition, and bacterial food concentration. To facilitate unbiased phenotype assessment throughout the lifespan, we used a Wmicrotracker ONE reader to monitor worm movement and viability in a multi-well plate. The overall fitness decline with aging using our method is comparable to that of worms maintained on solid agar. Lastly, using transgenic <i>C. elegans</i> carrying tauopathy, we demonstrated the ability of applying our optimized platform for high-throughput screening with a Z-factor of 0.7. Our novel method simplifies age-synchronized population maintenance, enhances progeny separation, and reduces costs, enabling high-throughput screening of compounds and RNAi libraries. These advancements greatly enhance the versatility of <i>C. elegans</i> as a model organism, offering a scalable platform for genetic and compound screening and for comprehensive investigations into drug discovery and disease mechanisms.