Fuel-Free Rolosense:Viral Sensing Using DiffusionalParticle Tracking

The clinical significance of human coronaviruses in more severe respiratory illnesses has recently been shown to be higher than was previously assumed. Rapid and reliable diagnosis of human coronavirus infections therefore becomes indispensable in a routine clinical setting. In this study, we present a very sensitive and specific TaqMan-based, real-time quantitative reverse transcriptase PCR (qRT-PCR) for the rapid detection and quantitation of human coronaviruses (HCoVs) OC43 and 229E. Absolute viral load measurement in clinical samples was achieved through the construction of in-house HCoV OC43 and 229E cRNA standards for the generation of a standard curve. The HCoV OC43 assay allows quantitation over a range from 20 to 2 x 10(8) RNA copies per reaction mixture (5 microl RNA extract). When this is extrapolated to clinical samples, this corresponds to a detection range of 10(3) to 10(10) viral genome equivalents per ml. By using the HCoV 229E qRT-PCR assay, viral RNA copies ranging from 200 to 2 x 10(9) per reaction mixture can be detected, which corresponds to 10(4) to 10(11) viral genome equivalents per ml sample. A total of 100 respiratory samples screened for the presence of HCoVs OC43 and 229E by using conventional RT-PCR were assessed in parallel by the qRT-PCR assays. By use of the real-time qRT-PCR techniques, the detection rate of HCoVs OC43 and 229E increased from 2.0% to 3.1% and from 0.3% to 2.5%, respectively. The real-time qRT-PCR assays described here allow the rapid, specific, and sensitive laboratory detection and quantitation of human coronaviruses OC43 and 229E.

Respiratory coronavirus infections in children younger than two years of age.

Improving human coronavirus OC43 (HCoV-OC43) research comparability in studies using HCoV-OC43 as a surrogate for SARS-CoV-2

We have developed a method for the rapid collection and detection of leukemia cells using a novel two-nanoparticle assay with aptamers as the molecular recognition element. An aptamer sequence was selected using a cell-based SELEX strategy in our laboratory for CCRF-CEM acute leukemia cells that, when applied in this method, allows for specific recognition of the cells from complex mixtures including whole blood samples. Aptamer-modified magnetic nanoparticles were used for target cell extraction, while aptamer-modified fluorescent nanoparticles were simultaneously added for sensitive cell detection. Combining two types of nanoparticles allows for rapid, selective, and sensitive detection not possible by using either particle alone. Fluorescent nanoparticles amplify the signal intensity corresponding to a single aptamer binding event, resulting in improved sensitivity over methods using individual dye-labeled probes. In addition, aptamer-modified magnetic nanoparticles allow for rapid extraction of target cells not possible with other separation methods. Fluorescent imaging and flow cytometry were used for cellular detection to demonstrate the potential application of this method for medical diagnostics.

In the March 2009 issue of the Journal of Clinical Microbiology, Sato et al. describe the detection of viruses in human adenoid tissue samples by using PCR assays (11). We wish to add our experience from a similar study. Thirty tissue samples were obtained from 30 individual children admitted for adenoidectomy at Bonn University Medical Centre, Department of Otorhinolaryngology. The median age at adenoidectomy was 4 years (range, 1 to 9 years); samples were taken between December 2007 and February 2008. Ear, nose, and throat specialists determined the indication for surgery. All children had clinical symptoms due to hypertrophy of adenoids. At the time of surgery, none displayed symptoms of acute respiratory infection. RNA extraction of 25 mg of tissue was done using a QIAamp RNeasy tissue kit (Qiagen, Hilden, Germany) according to the manufacturer's instructions. Published real-time reverse transcription-PCR assays were used to detect influenza A and B viruses (12), parainfluenza viruses 1 and 2 (5), rhinoviruses (9), respiratory syncytial viruses A and B (6), human bocavirus (10), enteroviruses (13), adenoviruses (3), human metapneumovirus (1), and human coronaviruses OC43, 229E, and NL63 (2), respectively. In 29/30 (97%) samples, at least a single pathogen was detectable by PCR. Human rhinoviruses were the most frequent in 20/30 (67%) samples, followed by human bocavirus in 16/30 (53%), parainfluenza virus 2 in 11/30 (36%), enteroviruses in 11/30 (36%), adenoviruses in 10/30 (30%), and respiratory syncytial viruses A and B in 7/30 (23%), respectively. Pathogens less frequently detected included influenza A and B viruses in 2/30 (6%) and 1/30 (3%) samples, respectively. Human coronaviruses 229E, OC43, and NL63, human metapneumovirus, and parainfluenza virus 1 were not detectable. A total of 25/30 (83%) samples yielded multiple positive results. This is the first study to evaluate a broad spectrum of respiratory viruses in adenoid samples from children undergoing elective surgery in the middle of the respiratory season. Although prolonged shedding of viral RNA after respiratory infections has been demonstrated for various pathogens, the frequent detection of viral RNA in tissue samples is surprising (4). Intriguingly, similar to the study of Sato et al., all children did not display symptoms typically associated with infection with a respiratory virus at the time of surgery. This finding supports the notion of a longer than previously anticipated persistence of viral nucleic acids. Sato et al. already speculated on a normal viral flora and a chronicity of selected respiratory viruses (11), which is supported by our data and might play a role with respect to the immune response. However, to what extent virus persistence can contribute to inflammation and subsequent hypertrophy needs to be further investigated. Of note, the findings presented here strengthen the hypothesis that positive PCR results from nasopharyngeal specimens should be interpreted with caution in asymptomatic patients, though the contribution of tissue-resident virus to positive PCR results has not been explicitly shown. The proportion of detected respiratory viruses most likely reflects their increased prevalence in the winter months. Interestingly, a high proportion of human bocavirus-positive adenoid samples was detected, supporting the notion of persistence in adenoids (8). Similar to that found in other studies, a high rate of viral coinfections was detectable (7). It was hypothesized that covirus-induced cellular damage, which can trigger cell division, might indeed contribute to bocavirus reactivation and replication (8). Coronaviruses were detected neither by Sato et al. nor in this study, indicating that these agents instead account for short-lived acute infections. In conclusion, using sensitive real-time PCR assays, we could demonstrate a spectrum of respiratory viruses in the adenoids of asymptomatic children in the respiratory season.

This study was conducted to investigate the respiratory viruses and subtyping of influenza A virus when positive by multiplex PCR in patients with flu-like symptoms, after the pandemic caused by influenza A (H1N1)pdm09. Nasopharyngeal swab samples collected from 700 patients (313 female, 387 male; age range: 24 days-94 yrs, median age: 1 yr) between December 2010 - January 2013 with flu-like symptoms including fever, headache, sore throat, rhinitis, cough, myalgia as defined by the World Health Organization were included in the study. Nucleic acid extractions (Viral DNA/RNA Extraction Kit, iNtRON, South Korea) and cDNA synthesis (RevertAid First Strand cDNA Synthesis Kits, Fermentas, USA) were performed according to the manufacturer's protocol. Multiplex amplification of nucleic acids was performed using DPO (dual priming oligonucleotide) primers and RV5 ACE Screening Kit (Seegene, South Korea) in terms of the presence of influenza A (INF-A) virus, influenza B (INF-B) virus, respiratory syncytial virus (RSV), and the other respiratory viruses. PCR products were detected by automated polyacrylamide gel electrophoresis using Screen Tape multiple detection system. Specimens which were positive for viral nucleic acids have been further studied by using specific DPO primers, FluA ACE Subtyping and RV15 Screening (Seegene, South Korea) kits. Four INF-A virus subtypes [human H1 (hH1), human H3 (hH3), swine H1 (sH1), avian H5 (aH5)] and 11 other respiratory viruses [Adenovirus, parainfluenza virus (PIV) types 1-4, human bocavirus (HBoV), human metapneumovirus (HMPV), rhinovirus types A and B, human coronaviruses (HCoV) OC43, 229E/NL63] were investigated with those tests. In the study, 53.6% (375/700) of the patients were found to be infected with at least one virus and multiple respiratory virus infections were detected in 15.7% (59/375) of the positive cases, which were mostly (49/59, 83%) in pediatric patients. RSV and rhinovirus coinfections were the most prevalent (18/29, 62.7%) dual infections. The distribution of 436 respiratory viruses identified from 375 patients were as follows; 189 (43.3%) RSV, 93 (21.4%) rhinovirus, 86 (19.8%) INF-A, seven (1.6%) INF-B, 22 (5%) PIV types 1-3, 14 (3.2%) HMPV, 11 (2.5%) HCoV, nine (2%) HBoV, and five (1.2%) adenovirus. Fifty-five (64%) out of 86 INF-A viruses were subtyped as hH3, 24 (27.9%) were sH1 and seven (8.1%) were hH1. Avian H5 was not detected in any samples. The overall prevalence rates of INF-A, INF-B, RSV and other respiratory viruses were 12%, 1%, 27%, and 14.6%, respectively. RSV was the most prevalent respiratory agent in pediatric (161/313, 51%) cases, while INF-A virus in adult (24/62, 38.7%) patients. Influenza viruses were detected as responsible pathogens in 13.3% (93/700) of the patients with flu-like symptoms. Among the cases, a 1-month-old baby was infected with three virus strains (INF-A hH1+INF-A sH1+HCoV OC43) and a 82-year-old patient was infected with two INF-A virus subtypes (hH3 + sH1). INF-A viruses were mostly detected (79/86) in winter period, from December to March. INF-A virus sH1, was the most prevalent subtype in flu cases till February 2011 (22/86), after replaced by INF-A virus hH3. Beginning from February 2012, a significant increase observed in the cases infected with INF-A virus subtype hH3 (39/86). In conclusion, the identification and surveillance of influenza virus types and subtypes circulating in populations have importance both for epidemiological data and selection of vaccine strains.

The ultimate detection limit in analytic chemistry and biology is the single molecule. Commonly, fluorescent dye labels or enzymatic amplification are employed. This requires additional labeling of the analyte, which modifies the species under investigation and therefore influences biological processes. Here, we utilize single gold nanoparticles to detect single unlabeled proteins with extremely high temporal resolution. This allows for monitoring the dynamic evolution of a single protein binding event on a millisecond time scale. The technique even resolves equilibrium coverage fluctuations, opening a window into Brownian dynamics of unlabeled macromolecules. Therefore, our method enables the study of protein folding dynamics, protein adsorption processes, and kinetics as well as nonequilibrium soft matter dynamics on the single molecule level.

Objective To evaluate the prevalence and clinical features of human Coronavirus OC43 （HCoV-OC43） in adult patients with acute respiratory infections （ARI） in Beijing. Methods Nasopharyngeal swab specimens were collected from 559 adult patients with ARI. HCoV-OC43 infection was detected using two sets of OneStep reverse transcription polymerase chain reaction （ OneStep RT-PCR） , which targeted the spike and nucleocapsid coding region. Results The prevalence of HCoV-OC43 was 12.52% （95% CI： 9.78%-15.26% ）, and the epidemic peak was in autumn. The dominant clinical presentations of HCoV-OC43 were fever, sore throat, headache, cough, nasal stuffiness, nasal discharge, and so on; 8 patients showed gastrointestinal symptoms such as diarrhea and vomiting. Statistically, nasal stuffiness was the most representative clinical presentation. Coinfection of HCoV-OC43 with other respiratory viruses was shown to be 35.71% （25/70, 95% CI： 24.49%-46.93%）. Conclusion With sensitive molecular detection techniques and nasopharyngeal swabs, high rate of HCoV-OC43 infection was achieved in adult patients with ARI in Beijing. Key words: Coronavirus 0C43, human; Reverse transcription polymerase chain reaction; Respiratory tract infections

Rapid and sensitive detection of foot-and-mouth disease virus in tissues by enzymatic RNA amplification of the polymerase gene

The recent pandemic of SARS-CoV-2 has underscored the critical need for rapid and precise viral detection technologies. Point-of-care (POC) technologies, which offer immediate and accurate testing at or near the site of patient care, have become a cornerstone of modern medicine. Prokaryotic Argonaute proteins (pAgo), proficient in recognizing target RNA or DNA with complementary sequences, have emerged as potential game-changers. pAgo present several advantages over the currently popular CRISPR/Cas systems-based POC diagnostics, including the absence of a PAM sequence requirement, the use of shorter nucleic acid molecules as guides, and a smaller protein size. This review provides a comprehensive overview of pAgo protein detection platforms and critically assesses their potential in the field of viral POC diagnostics. The objective is to catalyze further research and innovation in pAgo nucleic acid detection and diagnostics, ultimately facilitating the creation of enhanced diagnostic tools for clinic viral infections in POC settings.

Signal-on photoelectrochemical biosensor for microRNA detection based on Bi2S3 nanorods and enzymatic amplification

NanomedicineVol. 6, No. 8 EditorialNanoparticles for rapid detection of microbial threatsXiaoning Li & Vincent M RotelloXiaoning LiDepartment of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003, USASearch for more papers by this author & Vincent M Rotello† Author for correspondenceDepartment of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003, USA. Search for more papers by this authorEmail the corresponding author at rotello@chem.umass.eduPublished Online:25 Oct 2011https://doi.org/10.2217/nnm.11.129AboutSectionsView ArticleView Full TextPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinkedInReddit View article"Nanoparticles for rapid detection of microbial threats." , 6(8), pp. 1295–1296Keywords: biosensorsmicrobial detectionnanoparticlesBibliography1 Allen MJ, Edberg SC, Reasoner DJ. Heterotrophic plate count bacteria – what is their significance in drinking water? Int. J. Food Microbiol.92,265–274 (2004).Crossref, Medline, Google Scholar2 Burtscher C, Wuertz S. Evaluation of the use of PCR and reverse transcriptase PCR for detection of pathogenic bacteria in biosolids from anaerobic digestors and aerobic composters. Appl. Environ. Microbiol.69,4618–4627 (2003).Crossref, Medline, CAS, Google Scholar3 Van Dyck E, Ieven M, Pattyn S, Van Damme L, Laga M. Detection of Chlamydia trachomatis and Neisseria gonorrhoeae by enzyme immunoassay, culture, and three nucleic acid amplification tests. J. Clin. Microbiol.39,1751–1756 (2001).Crossref, Medline, CAS, Google Scholar4 Mao XL, Yang LJ, Su XL, Li YB. A nanoparticle amplification based quartz crystal microbalance DNA sensor for detection of Escherichia coli O157:H7. Biosens. Bioelectron.21,1178–1185 (2006).Crossref, Medline, CAS, Google Scholar5 Ravindranath SP, Mauer LJ, Deb-Roy C, Irudayaraj J. Biofunctionalized magnetic nanoparticle integrated mid-infrared pathogen sensor for food matrixes. Anal. Chem.81,2840–2846 (2009).Crossref, Medline, CAS, Google Scholar6 Lee H, Sun E, Ham D, Weissleder R. Chip-NMR biosensor for detection and molecular analysis of cells. Nat. Med.14,869–874 (2008).Crossref, Medline, Google Scholar7 Ji J, Schanzle A, Tabacco MB. Real-time detection of bacterial contamination in dynamic aqueous environments using optical sensors. Anal. Chem.76,1411–1418 (2004).Crossref, Medline, CAS, Google Scholar8 You CC, Miranda OR, Rotello VM et al. Detection and identification of proteins using nanoparticle-fluorescent polymer ‘chemical nose’ sensors. Nat. Nanotech.2,318–323 (2007).Crossref, Medline, CAS, Google Scholar9 Phillips RL, Miranda OR, You CC, Rotello VM, Bunz UHF. Rapid and efficient identification of bacteria using gold-nanoparticle – poly(para-phenyleneethynylene) constructs. Angew. Chem. Int. Ed.47,2590–2594 (2008).Crossref, Medline, CAS, Google Scholar10 Miranda OR, Li X, Rotello VM, Bunz UHF et al. Colorimetric bacteria sensing using a supramolecular enzyme-nanoparticle biosensor. J. Am. Chem. Soc.133,9650–9653 (2011).Crossref, Medline, CAS, Google ScholarFiguresReferencesRelatedDetailsCited ByFast label-free identification of bacteria by synchronous fluorescence of amino acids7 September 2021 | Analytical and Bioanalytical Chemistry, Vol. 413, No. 27Water Disinfection Using Silver and Zinc Oxide Nanoparticles30 August 2021 | Journal of Nano Research, Vol. 69Polycyclic Aromatic Hydrocarbons (PAHs) in inland aquatic ecosystems: Perils and remedies through biosensors and bioremediationEnvironmental Pollution, Vol. 241Colorimetric enumeration of bacterial contamination in water based on β-galactosidase gold nanoshell activityEnzyme and Microbial Technology, Vol. 99Organic chemistry meets polymers, nanoscience, therapeutics and diagnostics2 August 2016 | Beilstein Journal of Organic Chemistry, Vol. 12Multiple strategies to activate gold nanoparticles as antibioticsNanoscale, Vol. 5, No. 18 Vol. 6, No. 8 Follow us on social media for the latest updates Metrics Downloaded 428 times History Published online 25 October 2011 Published in print October 2011 Information© Future Medicine LtdKeywordsbiosensorsmicrobial detectionnanoparticlesFinancial & competing interests disclosureSupport of the NIH (GM077173-05) is gratefully acknowledged. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.No writing assistance was utilized in the production of this manuscript.PDF download

It is significant to develop an efficient early detection and prediction method for ovarian cancer via a facile and low-cost approach. To address such issues, herein, we develop a novel circulating tumor cell (CTC) detection method to sensitively detect ovarian cancer by using a flexible graphene-based biosensor on polyethylene terephthalate (PET) substrate. The results show that the graphene-based flexible biosensor demonstrates sensitive and rapid detection for ovarian cancer cells: it delivers obvious different responses for cell culture medium and cancer solution, different cancer cells and cancer cell solution with different concentrations; it demonstrates high sensitivity for detecting several tens of ovarian cancer cells per ml; moreover, the flexible graphene biosensor is very suitable for rapid and sensitive detection of ovarian cancer cells within 5 s. This work provides a low-cost and facile graphene biosensor fabrication strategy to sensitively and rapidly detect / identify CTC ovarian cancer cells.Graphical

We present a novel assay for rapid and highly sensitive detection of specific nucleic acid fragments in human serum. In a magnetic modulation biosensing (MMB) system, magnetic beads and fluorescently labeled probes are attached to the target analyte and form a "sandwich" complex. An alternating external magnetic field gradient condenses the magnetic beads (and hence the target molecules with the fluorescently labeled probes) to the detection volume and sets them in a periodic motion, in and out of a laser beam. A synchronous detection enables the removal of background signal from the oscillating target signal without complicated sample preparation. The high sensitivity of the MMB system, combined with the specificity of a sandwich hybridization assay, enables detection of DNA fragments without enzymatic signal amplification. Here, we demonstrate the sensitivity of the assay by directly detecting the EML4-ALK oncogenic translocation sequence spiked in human serum. The calculated limit of detection is 1.4 pM, which is approximately 150 times better than a conventional plate reader. In general, the MMB-assisted SHA can be implemented in many other applications for which enzymatic amplification, such as PCR, is not applicable and where rapid detection of specific nucleic acid targets is required.

Pathogenic microorganisms and viruses can easily transfer from one host to another and cause disease in humans. The determination of these pathogens in a time- and cost-effective way is an extreme challenge for researchers. Rapid and label-free detection of pathogenic microorganisms and viruses is critical in ensuring rapid and appropriate treatment. Sensor technologies have shown considerable advancements in viral diagnostics, demonstrating their great potential for being fast and sensitive detection platforms. In this review, we present a summary of the use of an interferometric reflectance imaging sensor (IRIS) for the detection of microorganisms. We highlight low magnification modality of IRIS as an ensemble biomolecular mass measurement technique and high magnification modality for the digital detection of individual nanoparticles and viruses. We discuss the two different modalities of IRIS and their applications in the sensitive detection of microorganisms and viruses.