A review on fluorescence spectroscopic analysis of water and wastewater

In recent years, the application of fluorescence spectroscopy has been widely recognized in water environment studies. The sensitiveness, simplicity, and efficiency of fluorescence spectroscopy are proved to be a promising tool for effective monitoring of water and wastewater. The fluorescence excitation-emission matrix (EEMs) and synchronous fluorescence spectra have been widely used analysis techniques of fluorescence measurement. The presence of organic matter in water and wastewater defines the degree and type of pollution in water. The application of fluorescence spectroscopy to characterize dissolved organic matter (DOM) has made the water quality assessment simple and easy. With the recent advances in this technology, components of DOM are identified by employing parallel factor analysis (PARAFAC), a mathematical trilinear data modeling with EEMs. The majority of wastewater studies indicated that the fluorescence peak of EX/EM at 275nm/340nm is referred to tryptophan region (Peak T1). However, some researchers identified another fluorescence peak in the region of EX/EM at 225-237nm/340-381nm, which described the tryptophan region and labeled it as Peak T2. Generally, peak T is a protein-like component in the water sample, where T1 and T2 signals were derived from the <0.20µm fraction of pollution. Therefore, a more advanced approach, such as an online fluorescence spectrofluorometer, can be used for the online monitoring of water. The results of various waters studied by fluorescence spectroscopy indicate that changes in peak T intensity could be used for real-time wastewater quality assessment and process control of wastewater treatment works. Finally, due to its effective use in water quality assessment, the fluorescence technique is proved to be a surrogate online monitoring tool and early warning equipment.

Identification of an SRY-Negative 46,XX Infertility Male with a Heterozygous Deletion Downstream of SOX3 Gene

Background: A male individual with a non-chimeric karyotype of 46,XX is very rare. We explored the genetic aetiology of an infertility male with 46,XX and SRY negative.Methods: The peripheral blood sample was collected from the patient and subjected to a range of genetic testing, including conventional chromosomal karyotyping, short tandem repeat (STR) analysis for chromosome 13, 18, 21, X, Y contained SRY gene, azoospermia factor (AZF) deletion analysis including SRY gene, fluorescence in situ hybridization (FISH) with specific probes for CSP X/CSP Y/SRY, chromosomal microarray analysis (CMA) for genomic copy number variations (CNVs), and whole-genome analysis(WGA) for SNV&InDel variants, and the X chromosome inactivation (XCI) analysis for AR gene.Results: The patient was found to have a 46,XX karyotype. Neither AZFa+b+c nor SRY band was detected in the electrophoresis result. FISH results of both interphase cells with CSPX/CSPY probe and metaphase cells with CSPX/CSPY/SRY probe showed two green fluorescence signals at the centromeres of X chromosomes, but no Y chromosome and SRY fluorescence signal. QF-PCR results showed that the patient had only the AMELX fluorescence peak of the X chromosome but no AMELY and SRY fluorescence peak. All results of the Karyotype, FISH, and STR did not suggest limited Y chimerism. CMA showed he had a heterozygous deletion of about 867 kb in Xq27.1 (hg19: chrX: 138,612,879-139,480,163 bp), located at 104 kb downstream of SOX3 gene, including F9, CXorf66, MCF2 and ATP11C; Meanwhile, whole-genome sequencing also found no SNV&InDel mutation associated with abnormal sex development. 75% X chromosome inactivation was detected.Conclusions: Although the pathogenicity of 46,XX male patients with SRY negative remains unclear, SOX3 expression of the acquired function may be associated with partial testis differentiation. Therefore, copy number variation of SOX3 gene and regulatory region should be performed routinely for these patients.

Florescence Intensity Ratio Thermometer in the First Biological Window Based on Non-Thermally Coupled Energy Levels of Tm3+ and Ho3+ Ions

In this study, the up-conversion luminescence and optical temperature sensing properties of Ho3+/Tm3+/Yb3+-co-doped NaLuF4 phosphors were investigated. The visible (475, 540, and 650 nm) and near-infrared light (692 and 800 nm) radiated from 1Ho3+/4Tm3+/Yb3+-co-doped NaLuF4 phosphors were obvious enough for subsequent detection. The slopes in the lnI–lnP plot of the emissions located in the first biological window (650, 692, and 800 nm) were both ∼1.5, which mean that the power had little effect on the three fluorescence peak ratios. Based on the florescence intensity ratios (FIRs) of 650 and 692 nm, the relative sensing sensitivity reaches 0.029 K−1 (476 K). The relative sensing sensitivity based on the FIRs of 800 and 692 nm reaches 0.0076 K−1 (476 K). The results reveal that 1Ho3+/4Tm3+/Yb3+-co-doped NaLuF4 phosphors have potential applications in FIR-based temperature sensing in biological tissue for their high sensing sensitivity. In addition, the emission colors of the sample stabilize in the white light region as the temperature increased from 303 to 467 K, implying that it can also be used in white display.

Accumulation of Uroporphyrin I in Necrotic Tissues of Squamous Cell Carcinoma after Administration of 5-Aminolevulinic Acid

5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence is widely used for the intraoperative detection of malignant tumors. However, the fluorescence emission profiles of the accompanying necrotic regions of these tumors have yet to be determined. To address this, we performed fluorescence and high-performance liquid chromatography (HPLC) analyses of necrotic tissues of squamous cancer after 5-ALA administration. In resected human lymph nodes of metastatic squamous cell carcinoma, we found a fluorescence peak at approximately 620 nm in necrotic lesions, which was distinct from the PpIX fluorescence peak at 635 nm for viable cancer lesions. Necrotic lesions obtained from a subcutaneous xenograft model of human B88 oral squamous cancer also emitted the characteristic fluorescence peak at 620 nm after light irradiation: the fluorescence intensity ratio (620 nm/635 nm) increased with the energy of the irradiation light. HPLC analysis revealed a high content ratio of uroporphyrin I (UPI)/total porphyrins in the necrotic cores of murine tumors, indicating that UPI is responsible for the 620 nm peak. UPI accumulation in necrotic tissues after 5-ALA administration was possibly due to the failure of the heme biosynthetic pathway. Taken together, fluorescence imaging of UPI after 5-ALA administration may be applicable for the evaluation of tumor necrosis.

Stereochemical Geometries and Photoluminescence in Pseudo-Halido-Zinc(II) Complexes. Structural Comparison between the Corresponding Cadmium(II) Analogs

Six pseudohalide zinc(II) containing a variety of N-donor auxiliary amines were structurally characterized. These include two mononuclear trigonal bipyramidal [Zn(NTB)(N3)]ClO4·½H2O (3) and [Zn(TPA)(NCS)]ClO4 (4), two distorted octahedral [Zn(1,8-damnph)2(dca)2] (5) and [Zn(8-amq)2(dca)2] (6a) as well as two 1D polymeric chains catena-[Zn(isq)2(μ1,5-dca)2] (7) and catena-[Zn(N,N-Me2en)2(μ1,5-dca)]dca (8), where NTB = tris(2-benzimidazolylmethyl)amine, TPA = tris(2-pyridylmethyl)amine, 1,8-damnph = 1,8-diaminonaphthalene, 8-amq = 8-amino-quinoline, isq = isoquinoline (isq) and N,N-Me2en = N,N-dimethylethylenediamine. In general, with the exception of 6 and 8, the complexes exhibited luminescence emission in MeOH associated with red shift of the emission maxima, and the strongest visible fluorescence peak was detected at 421 nm (λex = 330 nm) in the case of Complex 5.

Study On Hydrogeochemical Characteristics of Deeply Buried Mining Area In Inner Mongolia - Shaanxi Province, China

In order to distinguish the differences of hydrogeochemical characteristics between coal measures strata and aquifers on the roof of deep buried mining areas in Inner Mongolia-Shaanxi, China, this paper adopted inorganic components, environmental isotopes and organic components to study water quality comprehensively. The results show that the deep buried mining area in Inner Mongolia-Shaanxi belongs to Mu Us Desert, and the surface is covered by aeolian sand, so it has excellent precipitation infiltration capacity. Mineralization of surface water and Quaternary water < 500mg/L, the cation is mainly Ca2+, the anion is mainly HCO3−, which belongs to HCO3-Ca·Mg type water. The Cretaceous Zhidan Group is in unconformable contact with the Quaternary, and constitutes a unified water-bearing complex on the whole, which makes Zhidan Group have a better supply water source, and its inorganic water quality characteristics are close to the Quaternary water; The deep aquifer is affected by the Anding formation relative impermeable layer and its recharge runoff condition is weak. The salinity of Jurassic water is generally > 3500mg/L due to long-term water-rock action. The cation is dominated by Na+ and the anion is dominated by SO42−, which belongs to SO4-Na type water. According to the analysis of hydrochemical characteristics, there is no direct hydraulic connection between Luohe Formation and Zhiluo Formation. The characteristics of environmental isotopes show that the rainwater, surface water and Quaternary water in the study area belong to the modern groundwater, while Zhidan Group water is between the modern groundwater and the ancient water. The values of δD and δ18O in the deep Straight Rom Group and Yan’an Group are low, and the groundwater falls below the rainwater line of Ordos Basin with a deep circulation depth. Before mining, the groundwater is in the stagnant state with good closed conditions. The content of dissolved organic matter (TOC and UV254) in groundwater decreases gradually with the increase of aquifer depth; Fluorescence peaks in Area I and Area III mainly appeared in surface water and Quaternary water, and DOM sources in surface water were more abundant; The fluorescence peak in Area I also appears in the water of Zhidan Group, Straight Rom Group and Yan’an Group, and the fluorescence peak between Area I and Area II is a symbol; The fluorescence peak intensity of Cretaceous → Straight Rom Group in Area V area has an increasing trend, indicating that there are humus like DOM from other sources in the deep Straight Rom Group aquifer. In general, the comprehensive analysis of hydrochemical characteristics by various means can well distinguish the differences of hydrogeochemical characteristics among aquifers, which provides a scientific basis for the rapid and accurate discrimination of water situation and disaster in coal mines and the safe production.

Potential Military Cotton Textiles by Carbon Quantum Dots

Owing to the sensitivity for color vicissitude by exposing to UV irradiation, manufacturing of fluorescent fabrics is widely demanded to be exploited in camping, sensing and military purposes. Pyrimidine based heterocycles were investigated with excellent pharmacological activity, however, their photoluminescence activity was never been investigated till now. The presented approach demonstrate a quite novel route for manufacturing of potential military textiles (fluorescent/UV-protective cotton fabrics with micobicide activity) via exploitation of carbon quantum dots (CQDs) nucleated from pyrimidine based heterocycle (4-(2,4-dichlorophenyl)-6-oxo-2-thioxohexahydropyrimidine-5-carbonitrile, Target Molecule, TM). The synthesized TM & CQDs were separately immobilized within both of native and cationized cotton fabrics to obtain TM@cotton, CQDs@cotton, TM@Q-cotton and CQDs@Q-cotton fabrics. The estimated yellowness index, intensity of the fluorescence peak, UV-blocking activity and microbicide action, were all followed the order of CQDs@Q-cotton > TM@Q-cotton > CQDs@cotton > TM @cotton. CQDs@Q-cotton showed quite good durability, as after 5 washings, yellowness index was diminished from 26.5 to only 20.3, florescence intensity for CQDs@Q-cotton was decreased from 540 nm to 340 nm and transmission percent was increased from 7 % to 10 %. Moreover, even after 10 washings, microbial inhibition (as a percent) against E. coli, Staphylococcus aureus and Candida albicans was estimated to 63 %, 68 % and 67 %, respectively, while, UV protection factor (UPF) was diminished from 38.2 (very good) to 21.5 (good). The presented unique route was succeeded for manufacturing of durable fluorescent textiles that could be superiorly applied as potential military textiles.

Size-tunable and stable cesium lead-bromide perovskite nanocubes with near-unity photoluminescence quantum yield

Stable cesium lead bromide perovskite nanocrystals (NCs) showing near-unity photoluminescence quantum yield (PLQY), narrow emission profile, and tunable fluorescence peak in the green region can be considered the ideal class...

A New Retrieval of Sun-Induced Chlorophyll Fluorescence in Water from Ocean Colour Measurements Applied on OLCI L-1b and L-2

The retrieval of sun-induced chlorophyll fluorescence is greatly beneficial to studies of marine phytoplankton biomass, physiology, and composition, and is required for user applications and services. Customarily phytoplankton chlorophyll fluorescence is determined from satellite measurements through a fluorescence line-height algorithm using three bands around 680 nm. We propose here a modified retrieval, making use of all available bands in the relevant wavelength range, with the goal to improve the effectiveness of the algorithm in optically complex waters. For the Ocean and Land Colour Instrument (OLCI), we quantify a Fluorescence Peak Height by fitting a Gaussian function and related terms to the top-of-atmosphere reflectance bands between 650 and 750 nm. This algorithm retrieves, what we call Fluorescence Peak Height by fitting a Gaussian function upon other terms to top-of-atmosphere reflectance bands between 650 and 750 nm. This approach is applicable to Level-1 and Level-2 data. We find a good correlation of the retrieved fluorescence product to global in-situ chlorophyll measurements, as well as a consistent relation between chlorophyll concentration and fluorescence from radiative transfer modelling and OLCI/in-situ comparison. Evidence suggests, the algorithm is applicable to complex waters without needing an atmospheric correction and vicarious calibration, and features an inherent correction of small spectral shifts, as required for OLCI measurements.

Effect of Natural Organic Matter on the Ozonation Mechanism of Trimethoprim in Water

Trimethoprim (TMP) is often used for the treatment of various bacterial infections. It can be detected in water, and it is difficult to be biodegraded. In this study, the degradation mechanism of TMP through ozonation and the effect of humic acids (HA) were investigated. Excessive ozone (pH 6, 0 °C) could reduce the content of TMP to less than 1% in 30 s. However, when ozone (O3) was not excessive (pH 6, 20 °C), the removal efficiency of TMP increased with the increase of O3 concentration. Four possible degradation pathways of TMP in the process of ozonation were speculated: hydroxylation, demethylation, carbonylation, and cleavage. The presence of HA in water inhibit the generation of ozonation products of TMP. The excitation-emission matrices (EEM) analysis showed that with the extension of ozonation time, the fluorescence value in the solution decreased and the fluorescence peak blue shifted. These results indicated that the structure of HA changed in the reaction and was competitively degraded with TMP. According to the free radical quenching test, the products of pyrolysis, direct hydroxylation and demethylation were mainly produced by indirect oxidation.