Methods and Applications in Fluorescence最新文献

Editorial: MAF journal and conference build together.

IF 2.4 3区化学

Methods and Applications in Fluorescence Pub Date : 2024-12-17 DOI: 10.1088/2050-6120/ad9a9e

David J S Birch, Marcia Levitus, Yves Mély

引用次数: 0

Surface plasmon enhanced auto-fluorescence and Raman spectroscopy for low-level detection of biological pathogens.

IF 2.4 3区化学

Methods and Applications in Fluorescence Pub Date : 2024-12-16 DOI: 10.1088/2050-6120/ad9fd2

Anjika Panghal, Sathi Das, Pramila Thapa, Meenakshi Meenakshi, Anand Kumar, Priya Nagpal, Satish Kumar Dubey, Vivekanandan Perumal, Dalip Singh Mehta

{"title":"Surface plasmon enhanced auto-fluorescence and Raman spectroscopy for low-level detection of biological pathogens.","authors":"Anjika Panghal, Sathi Das, Pramila Thapa, Meenakshi Meenakshi, Anand Kumar, Priya Nagpal, Satish Kumar Dubey, Vivekanandan Perumal, Dalip Singh Mehta","doi":"10.1088/2050-6120/ad9fd2","DOIUrl":"https://doi.org/10.1088/2050-6120/ad9fd2","url":null,"abstract":"The current culture-based bacterial detection technique is time-consuming and requires an extended sample preparation methodology. We propose the potential of surface-enhanced Raman spectroscopy (SERS) and surface plasmon-enhanced auto-fluorescence spectroscopy (SPEAS) for the label-free identification and quantification of bacterial pathogens at low concentrations collecting its unique auto-fluorescence and Raman signatures utilising highly anisotropic three-dimensional nanostructures of silver nano dendrites (Ag-NDs). The SERS data facilitates qualitative bacterial identification using the spectral features coming from the bacterial cell wall compound, and the SPEAS data was utilised to gain unique auto-fluorescence spectra present on the bacterial cell wall with enhanced quantification. The enhancement of Raman and auto-fluorescence signals of Ag-NDs were first evaluated using rhodamine 6g (R6G) as a probe molecule that exhibits a significant enhancement of 106 and limit of detection (LOD) of 10-12 M for SERS and 15 fold intensity enhancement and LOD of 10-15 M for SPEAS measurements. Further, the SERS and SPEAS measurements of bacterial pathogens, such as Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), using the Ag-NDs were recorded, and the results exhibit high auto-fluorescence and Raman signal intensity for both the samples up to 100 cfu/ml for both modalities. The significant photon count and distinct emission range in SPEAS measurements of bacteria enables accurate quantification. Therefore, the comprehensive investigation of plasmonic enhancement of Ag-NDs for SPEAS and SERS techniques provides complementary information about molecules to enable accurate and quick identification and quantification of pathogens.","PeriodicalId":18596,"journal":{"name":"Methods and Applications in Fluorescence","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spectral properties of 4-methylumbelliferone in PVA films; long-lived room temperature phosphorescence.

IF 2.4 3区化学

Methods and Applications in Fluorescence Pub Date : 2024-12-10 DOI: 10.1088/2050-6120/ad9885

Bong Lee, Emma Alexander, Danh Pham, Mariusz Gagoś, Arkadiusz Matwijczuk, Zygmunt Gryczynski, Ignacy Gryczynski

引用次数: 0

Detection of antimicrobial-induced survival/dead bacteria via mEos4b photoconversion: a preliminary study. 通过 mEos4b 光电转换检测抗菌剂诱导的存活/死亡细菌：初步研究。

IF 2.4 3区化学

Methods and Applications in Fluorescence Pub Date : 2024-11-26 DOI: 10.1088/2050-6120/ad92f1

Ilknur Yilmaz, Humeyra Demir, Aleyna Eslem Tureyen, Tulin Ozbek

{"title":"Detection of antimicrobial-induced survival/dead bacteria via mEos4b photoconversion: a preliminary study.","authors":"Ilknur Yilmaz, Humeyra Demir, Aleyna Eslem Tureyen, Tulin Ozbek","doi":"10.1088/2050-6120/ad92f1","DOIUrl":"10.1088/2050-6120/ad92f1","url":null,"abstract":"The escalating prevalence of hospital-acquired infections poses a critical challenge for healthcare systems worldwide. Effective management requires rapid identification of pathogens and their antibiotic resistance profiles. In this study, we utilized the photoconvertible mEos4b protein, which transitions from green to red fluorescence upon blue light exposure, to distinguish live from dead bacteria. The mEos4b gene was cloned into a prokaryotic vector and expressed inEscherichia coliBL21. The Minimum Inhibitory Concentration (MIC) of the transgenic bacteria was determined for five antibiotics, followed by a post-antibiotic effect assessment over a two-hour exposure period. The optimal photoconversion time for mEos4b was established as 90 s, and confocal microscopy was used to visualize live (green) and dead (red) cells post-exposure. The mEos4b-TR system proved highly specific, accurately distinguishing live and dead bacteria without producing false positives, even in control groups, which is a common issue in commercial live-dead kits. By relying on cellular metabolic activity rather than dyes, this system minimizes nonspecific interactions and contamination, making it more reliable than traditional methods prone to false readings. These results highlight the potential of the mEos4b-TR system as a superior alternative for rapid, precise bacterial viability assessments, particularly in determining antibiotic susceptibility. This preliminary study demonstrates the system's differentiation of viable and non-viable cells, suggesting its potential application in future studies involving novel antibacterial agents to refine antibiotic sensitivity testing.","PeriodicalId":18596,"journal":{"name":"Methods and Applications in Fluorescence","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142623968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Naphthylated LEGO-lipophosphonoxin antibiotics used as a fluorescent tool for the observation of target membrane perturbations preceding its disruption. 萘基 LEGO-lipophopsphonoxin 抗生素被用作一种荧光工具，用于观察目标膜在被破坏之前的扰动。

IF 2.4 3区化学

Methods and Applications in Fluorescence Pub Date : 2024-11-05 DOI: 10.1088/2050-6120/ad8abf

Tereza Dolejšová, Petra Lišková, Nitjawan Sahatsapan, Viktor Mojr, Radek Pohl, Hana Brzobohatá, Milica Dugić, Tomáš Křížek, Lukasz Cwiklik, Gabriela Mikušová, Dominik Rejman, Radovan Fišer

{"title":"Naphthylated LEGO-lipophosphonoxin antibiotics used as a fluorescent tool for the observation of target membrane perturbations preceding its disruption.","authors":"Tereza Dolejšová, Petra Lišková, Nitjawan Sahatsapan, Viktor Mojr, Radek Pohl, Hana Brzobohatá, Milica Dugić, Tomáš Křížek, Lukasz Cwiklik, Gabriela Mikušová, Dominik Rejman, Radovan Fišer","doi":"10.1088/2050-6120/ad8abf","DOIUrl":"10.1088/2050-6120/ad8abf","url":null,"abstract":"Linker-Evolved-Group-Optimized-Lipophosphonoxins (LEGO-LPPO) are small synthetic modular peptidomimetics with promising antimicrobial activity. The LEGO-LPPO mechanism of antibacterial action has been determined to be the depolarization and disruption of bacterial membranes. Their modular nature is advantageous for fine tuning their biological properties. In order to optimize the structure of LEGO-LPPO even further, it is important to understand the interaction of LEGO-LPPO with bacterial membranes at the molecular level. In this work, we present the synthesis of five LEGO-LPPO (designated as1_naph2-4-G to5_naph2-4-G) molecules bearing fluorescent naphtylethyl moieties and their usage in the study of LEGO-LPPO behaviour in the membrane. Our goal was to characterize fluorescently labelled LEGO-LPPO under conditions that do not completely disrupt the membrane, mostly in the form of membrane-bound monomers. We observed the intramolecular interactions of hydrophobic modules of1_naph2-4-G in the buffer by detecting dynamic naphthyl excimers and their disappearance after1_naph2-4-G bind into the membranes. In the membrane, the molecule1_naph2-4-G slightly affects the membrane fluidity of DOPG membranes above the phase transition. The naphthyl fluorophore itself has fast and almost unrestricted rotation around ethylene linking groups (rinf= 0.010), which indicates a considerable chaotropic effect of the hydrophobic modules of1_naph2-4-G at the given depth of the membrane.1_naph2-4-G proved to be a useful model for observing the interaction of LEGO-LPPO antibiotics with the phospholipid bilayer enabling us to decipher its effects on membrane state and dynamics; its binding and penetration into the membrane, its structure and the particular depth that it occupies.","PeriodicalId":18596,"journal":{"name":"Methods and Applications in Fluorescence","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142503960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

CombiningNitellopsis obtusaautofluorescence intensity and F680/F750 ratio to discriminate responses to environmental stressors. 结合拟南芥自发荧光强度和 F680/F750 比率来区分对环境胁迫的反应。

IF 2.4 3区化学

Methods and Applications in Fluorescence Pub Date : 2024-08-21 DOI: 10.1088/2050-6120/ad6ca2

Ausrine Navickaite, Vilmantas Pupkis, Agne Kalnaityte-Vengeliene, Indre Lapeikaite, Vilma Kisnieriene, Saulius Bagdonas

{"title":"CombiningNitellopsis obtusaautofluorescence intensity and F680/F750 ratio to discriminate responses to environmental stressors.","authors":"Ausrine Navickaite, Vilmantas Pupkis, Agne Kalnaityte-Vengeliene, Indre Lapeikaite, Vilma Kisnieriene, Saulius Bagdonas","doi":"10.1088/2050-6120/ad6ca2","DOIUrl":"10.1088/2050-6120/ad6ca2","url":null,"abstract":"Detection of autofluorescence parameters is a useful approach to gain insight into the physiological state of plants and algae, but the effect of reabsorption hinders unambiguous interpretation ofin vivodata. The exceptional morphological features ofNitellopsis obtusamade it possible to measure autofluorescence spectra along single internodal cells and estimate relative changes in autofluorescence intensity in selected spectral regions at room temperatures, avoiding the problems associated with thick or optically dense samples. The response of algal cells to controlled white light and DCMU herbicide was analyzed by monitoring changes in peak FL intensity at 680 nm and in F680/F750 ratio. Determining the association between the selected spectral FL parameters revealed an exponential relationship, which provides a quantitative description of photoinduced changes. The ability to discern the effect of DCMU not only in the autofluorescence spectra of dark-adapted cells, but also in the case of light-adapted cells, and even after certain doses of excess light, suggests that the proposed autofluorescence analysis ofN. obtusamay be useful for detecting external stressors in the field.","PeriodicalId":18596,"journal":{"name":"Methods and Applications in Fluorescence","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141902303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Mn²⁺doping and DDAB-assisted postpassivation on the structural and optical properties of CsPb(Cl/Br)₃halide perovskite nanocrystals. 掺杂 Mn2+ 和 DDAB 辅助后钝化对 CsPb(Cl/Br)3 卤化物包晶石纳米晶体的结构和光学特性的影响。

IF 2.4 3区化学

Methods and Applications in Fluorescence Pub Date : 2024-08-21 DOI: 10.1088/2050-6120/ad6ca1

Charu Dubey, Anjana Yadav, Santosh Kachhap, Sunil Kumar Singh, Govind Gupta, Satendra Pal Singh, Akhilesh Kumar Singh

{"title":"Effect of Mn2+doping and DDAB-assisted postpassivation on the structural and optical properties of CsPb(Cl/Br)3halide perovskite nanocrystals.","authors":"Charu Dubey, Anjana Yadav, Santosh Kachhap, Sunil Kumar Singh, Govind Gupta, Satendra Pal Singh, Akhilesh Kumar Singh","doi":"10.1088/2050-6120/ad6ca1","DOIUrl":"10.1088/2050-6120/ad6ca1","url":null,"abstract":"Cesium lead halide perovskite (CsPbX3; X = Cl, Br, I) nanocrystals showing intense band-edge emission and high photoluminescence quantum yield are known to be a potential candidate for application in optoelectronic devices. However, controlling toxicity due to the presence of Pb2+in lead-based halide perovskites is a major challenge for the environment that needs to be tackled cautiously. In this work, we have partially replaced Pb2+with Mn2+ions in the CsPb(Cl/Br)3nanocrystals and investigated their impact on the structural and optical properties. The Rietveld refinement shows that CsPbCl2Br nanocrystals possess a cubic crystal structure withPm3̅mspace group, the Mn2+doping results in the contraction of the unit cell. The CsPb(Cl/Br)3: Mn nanocrystals show a substantial change in the optical properties with an additional emission band at ∼588 nm through a d-d transition, changing the emission color from blue to pink. Here, a didodecyldimethylammonium bromide (DDAB) ligand that triggers both anion and ligand exchange in the CsPb(Cl/Br)3: Mn nanocrystals have been used to regulate the exchange reaction and tune the emission color of halide perovskites by changing the peak position and the PL intensities of band-edge and Mn2+defect states. We have also shown that oleic acid helps in the desorption of oleylamine capping from the CsPb(Cl/Br)3: Mn nanocrystal surfaces and DDAB, resulting in the substitution of Cl-with Br-as well as provides capping with shorter branched length ligand which led to increase in the overall PL intensity by many folds.","PeriodicalId":18596,"journal":{"name":"Methods and Applications in Fluorescence","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141902304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multidimensional fluorescence spectroscopy of wine using synchronous excitation/emission matrices and time-resolved fluorescence interferometric detection. 使用同步激发/发射矩阵和时间分辨荧光干涉仪检测葡萄酒的多维荧光光谱。

IF 2.4 3区化学

Methods and Applications in Fluorescence Pub Date : 2024-07-26 DOI: 10.1088/2050-6120/ad64a9

Sakuya Mori, Christopher R Hall, Siobhan J Bradley, Trevor A Smith

引用次数: 0

Effect of molecular crowders on ligand binding kinetics with G-quadruplex DNA probed by fluorescence correlation spectroscopy. 通过荧光相关光谱探测分子挤出器对配体与 G 型四联 DNA 结合动力学的影响。

IF 2.4 3区化学

Methods and Applications in Fluorescence Pub Date : 2024-07-26 DOI: 10.1088/2050-6120/ad63f5

Parvez Alam, Ndege Simisi Clovis, Ajay Kumar Chand, Mohammad Firoz Khan, Sobhan Sen

{"title":"Effect of molecular crowders on ligand binding kinetics with G-quadruplex DNA probed by fluorescence correlation spectroscopy.","authors":"Parvez Alam, Ndege Simisi Clovis, Ajay Kumar Chand, Mohammad Firoz Khan, Sobhan Sen","doi":"10.1088/2050-6120/ad63f5","DOIUrl":"10.1088/2050-6120/ad63f5","url":null,"abstract":"Guanine-rich single-stranded DNA folds into G-quadruplex DNA (GqDNA) structures, which play crucial roles in various biological processes. These structures are also promising targets for ligands, potentially inducing antitumor effects. While thermodynamic parameters of ligand/DNA interactions are well-studied, the kinetics of ligand interaction with GqDNA, particularly in cell-like crowded environments, remain less explored. In this study, we investigate the impact of molecular crowding agents (glucose, sucrose, and ficoll 70) at physiologically relevant concentrations (20% w/v) on the association and dissociation rates of the benzophenoxazine-core based ligand, cresyl violet (CV), with human telomeric antiparallel-GqDNA. We utilized fluorescence correlation spectroscopy (FCS) along with other techniques. Our findings reveal that crowding agents decrease the binding affinity of CV to GqDNA, with the most significant effect-a nearly three-fold decrease-observed with ficoll 70. FCS measurements indicate that this decrease is primarily due to a viscosity-induced slowdown of ligand association in the crowded environment. Interestingly, dissociation rates remain largely unaffected by smaller crowders, with only small effect observed in presence of ficoll 70 due to direct but weak interaction between the ligand and ficoll. These results along with previously reported data provide valuable insights into ligand/GqDNA interactions in cellular contexts, suggesting a conserved mechanism of saccharide crowder influence, regardless of variations in GqDNA structure and ligand binding mode. This underscores the importance of considering crowding effects in the design and development of GqDNA-targeted drugs for potential cancer treatment.","PeriodicalId":18596,"journal":{"name":"Methods and Applications in Fluorescence","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141627150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fiber-optics based fluorescence detection. Part I: Basic concepts. 基于光纤的荧光检测。第一部分：基本概念。

IF 2.4 3区化学

Methods and Applications in Fluorescence Pub Date : 2024-07-23 DOI: 10.1088/2050-6120/ad5e5b

Bong Lee, Luca Ceresa, Danh Pham, Joseph Kimball, Emma Alexander, Xuan Ye, Ignacy Gryczynski, Zygmunt Gryczynski

{"title":"Fiber-optics based fluorescence detection. Part I: Basic concepts.","authors":"Bong Lee, Luca Ceresa, Danh Pham, Joseph Kimball, Emma Alexander, Xuan Ye, Ignacy Gryczynski, Zygmunt Gryczynski","doi":"10.1088/2050-6120/ad5e5b","DOIUrl":"10.1088/2050-6120/ad5e5b","url":null,"abstract":"Continuous in-line detection and process monitoring are essential for industrial, analytical, and biomedical applications. Lightweight, highly flexible, and low-cost fiber optics enable the construction of compact and robust hand-held devices forin situchemical and biological species analysis in both industrial and biomedicalin vitro/in vivodetection. Despite the broad range of fiber-optic based applications, we lack a good understanding of the parameters that govern the efficiency of light collection or the sensitivity of detection. Consequently, comparing samples of different optical density and/or geometry becomes challenging and can lead to misinterpretation of results; especially when we lack the approaches necessary to correct the detected signal (spectra) for artifacts such as inner-filter effect or scattering. Hence, in this work, we discuss factors affecting the signal detected by the fiber optic in the bare and lens-coupled flat-tipped configurations that lead to signal/spectral distortions. We also present a simple generic model describing the excitation profile and emission collection efficiency that we verify with experimental data. Understanding the principles governing the signal collected by the fiber will provide rationales for correcting the measured emission spectra and recovering the true emission profile of optically dense samples.","PeriodicalId":18596,"journal":{"name":"Methods and Applications in Fluorescence","volume":" ","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141492605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0