Dear Editor, The novel coronavirus (CoV) disease termed COVID-19 (coronavirus disease-19) caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) 1 is causing a massive pandemic worldwide, threatening public health systems across the globe. During this ongoing COVID-19 outbreak, nucleic-acid detection has played an important role in early diagnosis 2. To date, four protocols based on CRISPR for detecting SARS-CoV-2 have been published 3-6. Using lateral flow protocols, RNA samples harboring more than 1 × 10 4-1 × 10 5 copies/mL (SHERLOCK) or 1 × 10 4 copies/mL (DETECTR) can be detected within 1 hour. In addition to these reported efforts, we have also established a SARS-CoV-2 detection protocol based on our previously reported platform-CDetection (Cas12bmediated DNA detection) 7. By combining sample treatment protocols and nucleic-acid amplification methods with CDetection, we have established an integrated viral nucleic-acid detection platform-CASdetec (CRISPRassisted detection). The detection limit of CASdetec for SARS-CoV-2 pseudovirus is 1 × 10 4 copies/mL, with no cross-reactivity observed. Here, we present our assay design and optimization process, which could provide guidance for future CRISPR-based nucleic-acid detection assay development and optimization. To optimize the output of fluorescence signal, we designed and synthesized poly-T fluorescence-quenchers of varying nucleotide lengths, including 4 nt, 5 nt, 7 nt, 12 nt, 17 nt, 22 nt, and 27 nt. Of all the lengths tried, the 7 nt

Aging biomarkers are a combination of biological parameters to (i) assess age-related changes, (ii) track the physiological aging process, and (iii) predict the transition into a pathological status. Although a broad spectrum of aging biomarkers has been developed, their potential uses and limitations remain poorly characterized. An immediate goal of biomarkers is to help us answer the following three fundamental questions in aging research: How old are we? Why do we get old? And how can we age slower? This review aims to address this need. Here, we summarize our current knowledge of biomarkers developed for cellular, organ, and organismal levels of aging, comprising six pillars: physiological characteristics, medical imaging, histological features, cellular alterations, molecular changes, and secretory factors. To fulfill all these requisites, we propose that aging biomarkers should qualify for being specific, systemic, and clinically relevant. Supporting Information The supporting information is available online at 10.1007/s11427-023-2305-0. The supporting materials are published as submitted, without typesetting or editing. The responsibility for scientific accuracy and content remains entirely with the authors.