Metal-organic framework (MOF) is a class of crystalline porous solid materials which could be designed as sensors for bioactive molecules. In this study, charge transition between the ligand and the metal ions related emission and the ligand-based emission were formed simultaneously within a novel luminescent MOF with the copper reactive site as nodes. It can serve as a rare example of MOFs implicated ratiometric sensor for selective luminescent detection of H2S. The luminescent detection limitations for H2S is 0.21 μM, and it possesses a fast response of 30 s. The sensing mechanism is also discussed.Systematic Absence of Cross Peaks (SACPs) in a two-dimensional (2D) asynchronous spectrum, a sensitive indicator of the signal purity, is very important in analyzing bilinear data. However, identification of SACPs in practice remains a challenge because of noise in the corresponding 2D asynchronous spectrum. We firstly show that SACP can be identified via a statistical test using a large amount of 2D asynchronous spectra. To meet the practical demand that SACPs must be identified based on a single 2D asynchronous spectrum in many cases, we use a 2D quotient spectrum (Q (x, y)) as an effective auxiliary tool to recognize SACPs. The expectation of Q(x, y) is zero when (x, y) is within SACP or background regions in the corresponding 2D asynchronous spectrum. When (x, y) is in a cross-peak region, the expectation of the absolute value of Q(x, y) is a constant regardless of whether the cross-peak in a 2D asynchronous spectrum is strong or weak. Thus, a unified threshold can be set up to differentiate the SACP region from cross-peak region via the auxiliary 2D quotient spectrum. We have applied this approach on two real-world examples and satisfactory results have been obtained. This result demonstrates that the statistical test with a 2D quotient spectrum is applicable in real-world systems.In this paper, we have studied the structural, optical, dielectric and magnetic properties of Eu3+, Bi3+ co-doped LaVO4 phosphors prepared by solid state reaction method. Rietveld structural analysis of the samples confirms the monoclinic crystal structure with P21/n space group. The particles size of Eu3+ doped LaVO4 phosphor increased in presence of Bi3+ ion. The excitation spectrum of Eu3+, Bi3+ co-doped LaVO4 phosphor reveals bands due to charge transfer state (CTS) and electronic transitions of Eu3+ and Bi3+ ions. The Eu3+ doped LaVO4 phosphor gives intense red emission centred at 613 nm due to 5D0 → 7F2 transition of Eu3+ ion excited at 266, 355 and 394 nm wavelengths. When Bi3+ and Eu3+ ions are co-doped in the LaVO4 phosphor the photoluminescence intensity is enhanced upto two times. The photoluminescence intensity is largest for the 266 nm excitation. This is due to energy transfer from CTS and (1P1, 3P1) levels of the Bi3+ ion to 5D4 level of the Eu3+ ion and increase in the particles size of phosphor. The Eu3+, Bi3+ co-doped LaVO4 phosphors also show excellent dielectric and magnetic properties with a variation in frequency and magnetic field, respectively. Thus, the Eu3+, Bi3+ co-doped LaVO4 phosphor may be useful in fabricating displays devices, red emitting phosphors, dielectric capacitors and magnetic devices.The detection of Dopamine (DA) is significant for disease surveillance and prevention. However, the development of the precise and simple detection techniques is still at a preliminary stage due to their high tester requirements, time-consuming process, and low accuracy. In this work, we present a novel dual-emission ratiometric fluorescence sensing system based on a hybrid of carbon dots (CDs) and 7-amino-4-methylcoumarin (AMC) to quickly monitor the DA concentration. Linked via amide bonds, the CDs and AMC offered dual-emissions with peaks located at 455 and 505 nm, respectively, under a single excitation wavelength of 300 nm. Attributed to the fluorescence of the CDs and AMC in the nanohybrid system can be quenched by DA, the concentration of DA could be quantitatively detected by monitoring the ratiometric ratio change in fluorescent intensity. More importantly, the CDs-AMC-based dual-emission ratiometric fluorescence sensing system demonstrated a remarkable linear relationship in the range of 0-33.6 μM to detection of DA, and a low detection limit of 5.67 nM. Additionally, this sensor successfully applied to the detection of DA in real samples. Therefore, the ratiometric fluorescence sensing system may become promising to find potential applications in biomedical dopamine detection.Defects and deformation potential in quantum dots (QDs) were found to control the Raman modes however the disorder activated phonon (DAP) mode could not be seen in the cubic phase ZnS. With a maiden observation of a DAP mode the crucial role of surface defects, in particular, elemental 'S’ is reported. The DAP mode was seen with significant intensity at 153 cm-1 along with the LO mode at 347 cm-1 for the cubic ZnS. ZnS nanoparticles (NPs) of 3 to 5 nm were synthesized to understand origin of the DAP mode and its correlation with defects. The strongest DAP mode was observed in ZnS QDs of 3 nm size which showed the highest surface defects, in particular, the elemental type sulfur as revealed by the photoluminescence study. With increase in crystal size, the bulk-like property set in with the appearance of a weak DAP mode. Further, the reason behind the unclear observation of the mode in a cubic ZnS crystal near room temperature and effects of unaltered surface defects were investigated by the chemical functionalization with oleic acid and the heat treatment studies. The results revealed existence of a strong correlation between surface defects and synthesis conditions for observation of a DAP peak in cubic ZnS NPs.Trivalent chromium (Cr(III)) is considered to exhibit hormesis (bi-phasic dose-response) property, where low dose be beneficial and high dose shows toxic effect. The present work describe the development of a bimetallic Ag/Co-polyvinylpyrrolidone nanocomposite (Ag/Co-PVP NPs) probe to detect and quantify Cr(III) ions from aqueous samples. The hydrodynamic size and zeta potential of the particle was determined to be 29 ± 1.3 nm and -37.19 ± 2.4 mV respectively. The interaction of Cr(III) with Ag/Co-PVP probe showed drastic change in colour of NPs from dark brown to pale yellow, with corresponding blue shift, tapering width and increased peak intensity. The probe showed high specificity towards Cr(III) among the tested metal ions. A linearity was observed between various dilutions of Cr(III) ions (10 to 50 nM) and the absorbance of Ag/Co-PVP NPs at 428 nm with R2 value of 0.998. The minimum detectable limit of Cr(III) was calculated to be 0.6 nM. The influence of salinity, temperature and pH on detection was studied. The probe was found to detect Cr(III) at acidic pH effectively. Competitive metal ions did not interfere the detection of Cr(III). The water sample collected from Noyyal river was taken to estimate Cr(III) by using the prepared probe to ensure practical applicability. The sample contains 9.3 nM of Cr(III) that was cross verified with AAS analysis. Hence, it is understood that the reported probe can be used to detect Cr(III) selectively with high accuracy from aqueous samples. In addition, the particles also exhibited excellent photocatalytic activity under visible light. Ag/Co-PVP nanocomposites exhibited excellent antibacterial activity against both gram +ve (B. subtilis) and gram -ve (E. coli) bacteria.Monitoring of indoor air quality by detecting individual airborne pollutant is essential for maintaining a healthy indoor environment. UV absorption spectrophotometry coupled with gas chromatography offers a reliable, self-referenced and non-destructive technique for the identification and detection of gas molecules. This paper presents a deep-UV absorption spectrophotometer coupled with a micro gas-chromatography (μGC) for the detection of benzene, toluene, ethylbenzene and xylenes (BTEX). The spectrophotometer was developed using a low-volume gas cell made of PolyEther Ether Ketone (PEEK) polymer tube, connected with a portable deep-UV LED and photomultiplier tube. The performance of the detection unit was evaluated with different concentrations of toluene (5-100 ppm) in nitrogen and a sensitivity of 107.1 μAU/ppm with a limit of detection of 1.41 ppm was obtained. The detector was incorporated into a micro gas-chromatography setup and high quality chromatograms, having all the peaks separated with good repeatability were obtained for BTEX molecules. The deep-UV absorption spectrophotometer has low-volume, low-cost, and ease of development and integration. While demonstrated for BTEX in a nitrogen carrier gas, the spectrometer has the potential to be applied to chromatographic analysis of different analytes in gas or liquid media.In this work, a novel boronate-based fluorescent probe (FAM) for the endogenous detection of peroxynitrite (ONOO-) has been developed by using anthracycline as the fluorophore, arlyboronate as the recognition moiety, lipophilic cation as the mitochondrial targeting moiety. Upon reaction of the probe with ONOO-, the oxidation and subsequent hydrolysis of ONOO- to arlyboronate triggers quite rapid fluorescence off-on response, providing a sensitive and highly selective method for the detection of ONOO-. In addition, probe holds high sensitivity with the detection limit of 3.2 nM and excellent specificity including a series of biologically relevant reactive oxygen species. Importantly, FAM with good water solubility displays excellent performances for imaging endogenous peroxynitrite produced by RAW264.7 cells.

The global burden of death due to sepsis is considerable. Early diagnosis is essential to improve the outcome of this deadly syndrome. Yet, the diagnosis of sepsis is fraught with difficulties. Patients with blood stream infection (BSI) are at an increased risk of complications and death. The aim of this study was to determine the diagnostic accuracy of four readily available biomarkers to diagnose BSI in patients with suspected sepsis.

In this retrospective, observational, Electronic Medical Record based study we compared the accuracy of procalcitonin (PCT), serum lactate concentration, total white blood cell (WBC) count and the neutrophil-lymphocyte count ratio (NLCR) to diagnose BSI in adult patients presenting to hospital with suspected sepsis. Based on the blood culture results patients were classified into 1 of the following 5 groups i) negative blood cultures, ii) positive for a bacterial pathogen, iii) positive for a potential pathogen, iv) fungal pathogen and v) potential contaminant. Group 2 wassis, while the diagnosis of BSI should be considered in patients with a PCT above this threshold. The total WBC count and blood lactate concentration may not be reliable biomarkers for the diagnosis of BSI. The NLCR may be a useful screening test for BSI when PCT assays are not available.

Our results suggest that PCT of less than 0.5 ng/mL may be an effective screening tool to exclude BSI as the cause of sepsis, while the diagnosis of BSI should be considered in patients with a PCT above this threshold. The total WBC count and blood lactate concentration may not be reliable biomarkers for the diagnosis of BSI. The NLCR may be a useful screening test for BSI when PCT assays are not available.