Detection system of the intracellular nitric oxide in yeast by HPLC with a fluorescence detector

2020 ◽  
Vol 598 ◽  
pp. 113707
Author(s):  
Ryo Nasuno ◽  
Seiya Shino ◽  
Yuki Yoshikawa ◽  
Natsuko Yoshioka ◽  
Yuichi Sato ◽  
...  
2020 ◽  
Vol 27 (1) ◽  
pp. 60-66 ◽  
Author(s):  
C. Rumancev ◽  
A. Gräfenstein ◽  
T. Vöpel ◽  
S. Stuhr ◽  
A. R. von Gundlach ◽  
...  

A new Rococo 2 X-ray fluorescence detector was implemented into the cryogenic sample environment at the Hard X-ray Micro/Nano-Probe beamline P06 at PETRA III, DESY, Hamburg, Germany. A four sensor-field cloverleaf design is optimized for the investigation of planar samples and operates in a backscattering geometry resulting in a large solid angle of up to 1.1 steradian. The detector, coupled with the Xspress 3 pulse processor, enables measurements at high count rates of up to 106 counts per second per sensor. The measured energy resolution of ∼129 eV (Mn Kα at 10000 counts s−1) is only minimally impaired at the highest count rates. The resulting high detection sensitivity allows for an accurate determination of trace element distributions such as in thin frozen hydrated biological specimens. First proof-of-principle measurements using continuous-movement 2D scans of frozen hydrated HeLa cells as a model system are reported to demonstrate the potential of the new detection system.


2001 ◽  
Vol 6 (5) ◽  
pp. 291-303 ◽  
Author(s):  
Uwe Schobel ◽  
Michel Frenay ◽  
Danny A. Van Elswijk ◽  
Joanne M. McAndrews ◽  
Kelly R. Long ◽  
...  

A new screening technology that combines biochemical analysis with the resolution power of high-performance liquid chromatography (HPLC), referred to here as high-resolution screening (HRS) technique, is described. The capability of the HRS technology to analyze biologically active compounds in complex mixtures is demonstrated by screening a plant natural product extract library for estrogen receptor (ER) a and fi binding activity. The simultaneous structure elucidation of biologically active components in crude extracts was achieved by operating the HRS system in combination with mass spectrometry (MS). In contrast to conventional microtiter-type bioassays, the interactions of the extracts with the ER and the employed label, coumestrol, proceeded at high speed in a closed, continuous-flow reaction detection system, which was coupled directly to the outlet of a HPLC separation column. The reaction products of this homogeneous fluorescence enhancement-type assay were detected online using a flow-through fluorescence detector. Primary screening of the extract library was performed in the fast-flow injection analysis mode (FlowScreening) wherein the chromatographic separation system was bypassed. The library was screened at high speed, using two assay lines in parallel. A total of 98% of the identified hits were confirmed in a traditional 96-well microplate-based fluorescence polarization assay, indicating the reliability of the FlowScreening process. Active extracts were reassayed in a transcriptional activation assay in order to assess the functional activity of the bioactive extracts. Only functional active extracts were processed in the more time-consuming HRS mode, which was operated in combination with MS. Information on the number of active compounds, their retention times, the molecular masses, and the MS/MS-fingerprints as a function of their biological activity was obtained from 50% of the functional active extracts in real time. This dramatically enhances the speed of biologically active compound characterization in natural product extracts compared to traditional fractionation approaches.


2019 ◽  
Vol 90 (4) ◽  
pp. 046103 ◽  
Author(s):  
Hang Li ◽  
Wenqing Liu ◽  
Ruifeng Kan

2020 ◽  
Vol 15 (4) ◽  
pp. 552-559
Author(s):  
Si-Jia Liang ◽  
Jian-Guang Zhou

In recent years, drug abuse has become a major public health problem, drug-driving poses serious threats to the public security. For the urgent need to rapidly on-site screen drug evidence and drug abusers, we have developed a fluorescent drug detection device based on LED induction (FD-LED). The core part of the device is 365 nm high-intensity LED excitation light source, FD-LED detector' performance was tested by the fluorescent brightener OB. In this study, the FD-LED detector was evaluated, and the influence of baseline noise, baseline drift, sensitivity, detection limit and quantitative limit on the detector was analyzed, the result showed that the proposed detector had good stability and sensitivity, at the same time, the chromatographic detection conditions were set, the solution based on methamphetamine C1 sample was collocated, and combined with liquid chromatography, a detection system for methamphetamine was developed. The results showed that the minimum detection amount of the sample was 1.0 × 10–9 g/ml, and the signal-concentration relationship was obvious in the range of 1.0 ng/ml∼15.6 ng/ml. This device could provide an effective method for roadside drug testing and clinical diagnosis, and give helpful assistance to law enforcement officers.


2006 ◽  
Vol 952 ◽  
Author(s):  
Nathaniel Charles Cady ◽  
Scott J. Stelick ◽  
Carl Batt

ABSTRACTA miniaturized, fully-automated, PCR-based detection system has been developed for the rapid detection of the pathogenic bacteriumBacillus anthracis. Monolithic silicon DNA purification / real-time PCR chips were fabricated and tested for their ability to purify and detect DNA from bacterial cells. Using silica-coated microstructures and chemical-based lysis, nucleic acids could be isolated, washed and eluted for subsequent real-time PCR. These microstructures were integrated into a detection microchip containing two distinct regions, one for DNA purification and one for real-time PCR. Using an automated detection platform with integrated microprocessor, pumps, valves, thermocycler and fluorescence detector, target bacterial DNA was detected by real-time PCR amplification using SYBR Green fluorescent dye. As few as 40B. anthraciscells could be detected using this system with an average time for detection of 60 min. Detection was augmented by on-chip melting curve analysis capable of differentiating between positive and false-positive results.


2014 ◽  
Vol 63 (2) ◽  
pp. 203-209 ◽  
Author(s):  
Michael Neidrauer ◽  
Utku K. Ercan ◽  
Aparna Bhattacharyya ◽  
Joshua Samuels ◽  
Jason Sedlak ◽  
...  

Topical delivery of nitric oxide (NO) through a wound dressing has the potential to reduce wound infections and improve healing of acute and chronic wounds. This study characterized the antibacterial efficacy of an ointment containing NO-loaded, zinc-exchanged zeolite A that releases NO upon contact with water. The release rate of NO from the ointment was measured using a chemiluminescence detection system. Minimum bactericidal concentration assays were performed using five common wound pathogens, including Gram-negative bacteria (Escherichia coli and Acinetobacter baumannii), Gram-positive bacteria (Staphylococcus epidermidis and meticillin-resistant Staphylococcus aureus) and a fungus (Candida albicans). The time dependence of antimicrobial activity was characterized by performing log-reduction assays at four time points after 1–8 h ointment exposure. The cytotoxicity of the ointment after 24 h was assessed using cultured 3T3 fibroblast cells. Minimum microbicidal concentrations (MMCs) for bacterial organisms (5×107 c.f.u.) ranged from 50 to 100 mg ointment (ml media)−1; the MMC for C. albicans (5×104 c.f.u.) was 50 mg ointment (ml media)−1. Five to eight log reductions in bacterial viability and three log reductions in fungal viability were observed after 8 h exposure to NO–zeolite ointment compared with untreated organisms. Fibroblasts remained viable after 24 h exposure to the same concentration of NO–zeolite ointment as was used in antimicrobial tests. In parallel studies, full-thickness cutaneous wounds on Zucker obese rats healed faster than wounds treated with a control ointment. These data indicate that ointment containing NO-loaded zeolites could potentially be used as a broad-spectrum antimicrobial wound-healing dressing.


1998 ◽  
Vol 1626 (1) ◽  
pp. 120-128
Author(s):  
Gayle Mitchell ◽  
James D. Shinn

The cone penetrometer test (CPT) is an important tool for use in geotechnical and environmental site characterization for the transportation sector. Its role as both a primary investigation technique and as a component in an overall exploration strategy are explained. The types of sensors currently used with the CPT are discussed. Among the most promising new CPT technologies are a soil moisture probe and a fluorescence detection system. Laboratory and field results using a soil moisture probe jointly developed by Ohio University and Applied Research Associates for use with the CPT are presented. Also, application of the fuel fluorescence detector (FFD) for locating hydrocarbon contamination is presented, and typical data obtained with the FFD are illustrated and discussed.


1997 ◽  
Vol 86 (5) ◽  
pp. 1078-1087 ◽  
Author(s):  
Kyung W. Park ◽  
Hai B. Dai ◽  
Edward Lowenstein ◽  
Olivier N. Kocher ◽  
Frank W. Sellke

Background Respiratory epithelium releases substance(s) that can modulate bronchoconstriction in response to constrictive agonists and enhance bronchodilation in response to certain bronchodilators. The hypothesis that the bronchodilatory effect of isoflurane and halothane depends on the epithelium was tested in rat distal bronchial segments. Methods Wistar rat bronchial segments of the fourth order (diameter approximately 100 microns) were dissected. After preconstriction with 5-hydroxytryptamine, each bronchial segment was exposed to increasing concentrations of 0% to 3% isoflurane or 0% to 3% halothane under four conditions: after epithelial rubbing, after pretreatment with the nitric oxide synthase inhibitor NG-nitro-L-arginine, after pretreatment with the cyclooxygenase inhibitor indomethacin, or with no preintervention (control). Changes in bronchial diameter were monitored using an in vitro video detection system. Results Both isoflurane and halothane produced concentration-dependent bronchodilation (P < 0.001 for either anesthetic; 40% +/- 11% [mean +/- SD] dilation for 3% isoflurane and 57% +/- 10% dilation for 3% halothane). For both anesthetics, bronchodilation was significantly but incompletely attenuated by epithelial rubbing (12% +/- 7% dilation for 3% isoflurane [P < 0.01] and 31% +/- 10% dilation for 3% halothane [P < 0.01]), by pretreatment with indomethacin (20% +/- 8% dilation for 3% isoflurane [P < 0.02] and 21% +/- 9% dilation for 3% halothane [P < 0.001]), or by L-NNA (9% +/- 7% dilation for 3% isoflurane [P < 0.005] and 39% +/- 12% dilation for 3% halothane [P < 0.05]). Epithelial rubbing did not impair nitroprusside-associated bronchodilation. Conclusions Isoflurane- and halothane-mediated bronchodilation depends at least partially on the epithelium and may involve both a prostanoid and nitric oxide in distal rat bronchi.


Lab on a Chip ◽  
2015 ◽  
Vol 15 (13) ◽  
pp. 2754-2758 ◽  
Author(s):  
Russell H. Cole ◽  
Niek de Lange ◽  
Zev J. Gartner ◽  
Adam R. Abate

We present a compact and modular detection system capable of sub-nanomolar sensitivity utilizing an optical fibre array to encode spectral information recorded by a single photodetector.


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