Ultra-sensitive and specific detection of pathogenic nucleic acids using composite-excited hyperfine plasma spectroscopy combs sensitized by Au nanoarrays functionalized with 2D Ta2C-MXene.

Accurate and rapid screening techniques on a population scale are crucial for preventing and managing epidemics like COVID-19. The standard gold test for nucleic acids in pathogenic infections is primarily the reverse transcription polymerase chain reaction (RT-PCR). However, this method is not suitable for widespread screening due to its reliance on large-scale equipment and time-consuming extraction and amplification processes. Here, we developed a collaborative system that combines high-load hybridization probes targeting N and OFR1a with Au NPs@Ta2C-M modified gold-coated tilted fiber Bragg grating (TFBG) sensors to enable direct nucleic acid detection. Multiple activation sites of SARS-CoV-2 were saturable modified on the surface of a homogeneous arrayed AuNPs@Ta2C-M/Au structure based on a segmental modification approach. The combination of hybrid probe synergy and composite polarisation response in the excitation structure results in highly specific hybridization analysis and excellent signal transduction of trace target sequences. The system demonstrates excellent trace specificity, with a limit of detection of 0.2 pg/mL, and achieves a rapid response time of 1.5 min for clinical samples without amplification. The results showed high agreement with the RT-PCR test (Kappa index = 1). And the gradient-based detection of 10-in-1 mixed samples exhibits high-intensity interference immunity and excellent trace identification. Therefore, the proposed synergistic detection platform has a good tendency to curb the global spread of epidemics such as COVID-19.

Ultra-sensitive specific detection of nucleic acids in pathogenic infections by Ta2C-MXene sensitization-based ultrafine plasmon spectroscopy combs.

Accurate and rapid population-scale screening techniques based on SARS-CoV-2 RNA are essential in preventing and controlling the COVID-19 epidemic. However, the sensitivity and specificity of the assay signal are challenged by the problems of target dilution and sample contamination inherent in high-volume pooled testing. Here, we reported a collaborative system of high-loaded hybrid probes targeting N and OFR1a coupling with the novel Ta2C-M/Au/TFBG biosensor, providing high-intensity vector signals for detecting SARS-CoV-2. The method relies on a segmental modification approach to saturable modify multiple activation sites of SARS-CoV-2 on the high-performance Ta2C-M surface. The coupling of multi-site synergy with composite excited TFBG results in excellent signal transduction, detection limits (0.2 pg/mL), and hybridization efficiency. Without relying on amplification, the collaborative system achieved specific differentiation of 30 clinical samples in an average diagnostic time of 1.8 min. In addition, for the first time, a kinetic determination of dilution mixed samples was achieved and showed a high-intensity carrier signal and fantastic stability. Therefore, it can be used as a collaborative, integrated tool to play a massive role in the screening, prevention, and control of COVID-19 and other epidemics.

Electrochemical biosensing based on graphene for detection of the SARS-Co V-2 Nucleocapsid Protein

Monitoring and controlling infection is required in order to prevent the progression of the coronavirus severe acute respiratory syndrome 2(SARS-Co- V-2). To accomplish this goal, the development and implementation of sensitive, quick and accurate diagnostic methods are essential. Electrochemical sensors have exposed large application possibilities in biological detection due to the advantages of high sensitivity, short time-consuming and specificity. Here, we report the improvement of a sensitive electrochemical sensor capable of detecting the presence of the SARS-CoV-2 virus using graphene-modified interdigitated working electrodes functionalized with antibodies targeting the SARS-CoV-2 nucleocapsid protein (N protein). © 2022 IEEE.

Nanotechnology Solution for Early Detection of Micrometastatic Prostate Cancer After Radical Prostatectomy

The overall objective of this research proposal is to conduct the initial development of a rapid circulating tumor cell-based blood test that can identify men with micrometastatic disease in order to facilitate patient selection for salvage radiotherapy. Aim 1 of this study was do perform a technical validation study and Aim 2 to embark upon testing of banked clinical specimens then to test the new assay in the setting of the NRG-GU-006 clinical trial (salvage radiotherapy /- apalutamide). In the first year of work we have begun a series of key technical validation studies while completing the sample collection from the now fully accrued NRG-GU-006 trial. Due to COVID-19 there were delays in progress but due to rapid clinical accrual and regearing of our studies, this effort is still on time.

Molecular Changes in Circulating Cell Free DNA from BRCA1 and BRCA2 Mutation Carriers with Tubal Precursor Lesions and Occult Early High-GradeSerous Ovarian Cancer at Risk-Reducing Surgery

High grade serous ovarian cancer typically presents at advanced stage with a median survival of 44 months. Small precursors to this cancer are found in the fallopian tube and likely seed the ovary and peritoneum simultaneously. Early detection is urgently needed and ideally would detect precursor lesions. This award will determine if DNA methylation patterns exhibited in circulating cell-free DNA could be used to detect precursor lesions. During the first year of the award, application for province-wide (Ontario) research ethics approval was submitted to umbrella all 4 participating hospitals. This umbrella approval was obtained;however, we are awaiting final approval from 2 hospitals, which was delayed by the covid-19 shutdown. All research activities were halted (Covid-19 research being the exception) and department staff were redeployed to other hospital activities, causing a back-up of research-related activity. All centres are currently reopening (in stage 2) and study approval should be forthcoming. The Material Transfer Agreements have been started by Sinai Health System and once final REB/IRB approval has been obtained, these will be finalized across the all institutions. Patient samples for use in this study as identified have been secured and we are poised to complete the study once approvals are finalized.