New technologies are urgently required for reliable drug screening given a worldwide epidemic of prescription drug abuse and its devastating socioeconomic impacts on public health. Primary screening ...of drugs of abuse (DoA) currently relies on immunoassays that are prone to bias and are not applicable to detect an alarming array of psychoactive stimulants, tranquilizers, and synthetic opioids. These limitations impact patient safety when monitoring for medication compliance, drug substitution, or misuse/abuse and require follow-up confirmatory testing by more specific yet lower throughput instrumental methods. Herein, we introduce a high throughput platform for nontargeted screening of a broad spectrum of DoA and their metabolites based on multisegment injection–capillary electrophoresis–mass spectrometry (MSI–CE–MS). We demonstrate that MSI–CE–MS enables serial injections of 10 samples within a single run (<3 min/sample) where multiplexed electrophoretic separations are coupled to high resolution MS with full-scan data acquisition. Unambiguous drug identification was achieved by four or more independent parameters, including comigration with a deuterated internal standard or in silico prediction of electromigration behavior together with accurate mass, most likely molecular formula, as well as MS/MS as required for confirmation testing. Acceptable precision was demonstrated for over 50 DoA at 3 concentration levels over 4 days (median coefficient of variance = 13%, n = 117) with minimal ion suppression, isobaric interferences, and sample carry-over (<1%). This approach offers a rapid yet accurate method for simultaneous detection and identification of DoA at their recommended screening cutoff levels in human urine while allowing for systematic surveillance, specimen verification, and retrospective testing of designer drugs that elude conventional drug tests.
Cu3(OH)2(MoO4)2 cuboidal nanostructures (CMCNs) and their rGO/CMCNs nanocomposites have been synthesized by a simple hydrothermal route. These nanostructures show excellent enzyme mimicking activity ...at mildly acidic pH and room temperature. The colorimetric detection of dopamine has been done by analyzing the oxidation of the colorless TMB peroxidase substrate to the corresponding blue-colored product in the presence of H2O2. The long-term stability and robustness of the rGO/CMCNs nanocomposite have also been examined by maintaining the pH (acidic to basic) and temperature. The presence of H2O2 generated hydroxyl free radicals (·OH), the main reactive species, which was validated using the scavenger isopropanol. Further, rGO/CMCNs-assisted TMB oxidation offers a platform for the colorimetric detection of dopamine. Dopamine captures ·OH free radicals and inhibits the oxidation of TMB which leads to its detection. The limit of detection was found to be 0.17 μM with a linear range of 1–10 μM by colorimetric detection. The present sensing system was also used to quantify the dopamine concentration present in human blood serum and urine samples. rGO/CMCNs nanocomposites provide the significant peroxidase – mimicking activity for dopamine sensing.
Separation and treatment of human urine from domestic wastewater have been recognized as a sustainable alternative to conventional urban sanitation system, but the unique water quality of ...source-separated urine, such as high nutrient, insufficient alkalinity and low COD/nitrogen ratio, poses challenges to the biological nitrogen removal process. It was hypothesized that a physicochemical pre-treatment should be adopted to not only reduce nitrogen load but adjust water quality suitable for biological treatment. In this study, a vacuum thermal stripping process coupled to acid absorption was used as a pre-treatment to recover ammonia from hydrolyzed urine in the form of ammonium sulphate. The maximal ammonia mass transfer coefficient of 17.6 mm/h was obtained under 60 °C and 21.3 kPa 80% of the nitrogen in hydrolyzed urine was recovered in 3 h batch stripping experiments without pH adjustment, corresponding to a nitrogen recovery loading rate of 36 kg N/m3⋅d. The majority of organic matters were retained in urine solutions, thus COD/N and alkalinity/NH4+N ratios were elevated to 4.75 and 4.37, respectively. Phosphorus recovery could be simultaneously obtained in stripping process by adding MgCl2. The remaining nitrogen was effectively removed via short-cut nitrification and denitrification in an anoxic/oxic membrane bioreactor. More than 95% of overall nutrient recovery/removal from urine was achieved with a minimal consumption of external resources. The economic assessment of the technique showed that the recovery/removal of nutrients from 1 m3 of urine can make a profit of € 0.26.
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•Vacuum thermal stripping (VTS) was used to recover N from source-separated urine.•VTS recovered 80% N and adjusted C/N and alkalinity/N ratios in urine solution.•No external C source was required for biological N removal.•Over 95% P and N recovery/removal was achieved.
•Determination of ofloxacin in human urine and plasma samples, without the need of a pre-separation step.•Very fast ultrasound assisted dispersive µ-SPE coupled to spectrofluorimetry detection for ...selective analysis of ofloxacin.•Sensitive monitoring of traces of ofloxacin in the biological samples.•Magnetic core–shell mesoporous adsorbent can be fast and efficiently separated.•Reducing the amount of blood collected and minimizing difficulties with some kinds of patients.
In this research, a sensitive, simple and rapid ultrasound assisted dispersive micro solid-phase extraction (USAD-µSPE) was developed using a synthesized core–shell magnetic mesoporous nanocomposite (Fe3O4@nSiO2@mSiO2–NH2) as an efficient adsorbent for the preconcentration and spectrofluorometric determination of ofloxacin (OFL) in biological samples. The synthesized adsorbent was characterized using FT-IR spectroscopy, transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), energy dispersive X-ray (EDX) spectroscopy, thermogravimetric analysis (TGA) and Brunauer–Emmett–Teller (BET) analysis. The application of this magnetic nanocomposite as a sensitive solid phase for removal, preconcentration and spectrofluorometric quantification of trace amount of OFL was developed. Influence of various variables including pH, sorbent dosage, desorption solvent properties and sonication time on present method response was studied and optimized. The results showed that using the proposed method OFL can be determined in the linear concentration range of 1.0–500.0µgL−1 with a limit of detection as low as 0.21µgL−1 and relative standard deviation less than 2.5 (%). The results of human urine and blood plasma analysis showed that the method is a good candidate for biological sample analysis purposes.
In‐tube solid‐phase microextraction with a capillary column as extraction device can be directly coupled with high‐performance liquid chromatography systems (HPLC). The in‐tube solid‐phase ...microextraction technique has been continuously developed since it was introduced in 1997. New couplings have also been evaluated on the basis of state‐of‐the‐art HPLC instruments. Different types of capillaries (wall‐coated open tubular, porous layer open tubular, sorbent‐packed, porous monolithic rods, or fiber‐packed) with selective stationary phases (monoliths, magnetic nanoparticles, conducting polymers, restricted access materials, ionic liquids, carbon, deep eutectic solvents, and hybrid materials) have been developed to boost in‐tube solid‐phase microextraction performance (sorption capacity and selectivity). This technique has been successfully applied to analyze biological samples (serum, plasma, whole blood, hair, urine, milk, skin, and saliva) for therapeutic drug monitoring, to study biomarkers, to detect illicit drugs, to conduct metabolomics studies, and to assess exposure to drugs. This review describes current advances in in‐tube solid‐phase microextraction extraction devices and their application in bioanalysis.
•We developed a nanobiosensing platform combining with microfluidic enrichment for rapid and sensitive detection of pathogens.•Salmonella Typhimurium was detected in urine samples in real-time using ...a label-free method.•Sensitivity was improved by microfluidic enrichment.•The whole experiment was completed within 100 min.
Urinary tract infections are among the most common bacterial infections in humans, causing relapses and acute prostatitis as well as significant morbidity and high medical costs. In bacteria with low abundance in urological samples, which contain various contaminating factors, sample analyses should be conducted with meticulous care; therefore, emerging technologies can facilitate the characterization of disease-causing bacteria with more sensitivity, rapidity, and ease of use. In this study, we developed a highly sensitive nanobiosensor based on isothermal amplification combining microfluidic enrichment using a concanavalin A–functionalized microchannel with asymmetric herringbone groove arrays for rapid detection of pathogens. After optimization of enrichment and detection conditions, we demonstrated that Salmonella enterica serotype Typhimurium could be detected in urine samples (10 mL) at a concentration as low as 5 CFU/mL in real-time using a label-free method. Moreover, the use of microfluidic enrichment improved the sensitivity by 1.76 orders of magnitude. The whole experiment was completed within 100 min. This developed method has the potential to provide a simple, rapid, sensitive diagnostic platform and can be used in practical applications for detection of Salmonella or other pathogenic bacteria, causing urinary tract infections.
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•A highly sensitive microfluidic chip was developed for visualized detection of bacteria in urine at very low concentration.•Platinum nanoparticle probes acted as an efficient ...cocatalyst in combination with bacteria greatly amplify the signal.•Quantitative test can be completed in 1.5 h without external auxiliary equipment.•The point-of-care testing device provides a reliable strategy for early diagnosis of urinary tract infections.
Rapid and accurate detection of bacteria in urine is the key to improving the diagnostic efficiency of urinary tract infections. In this work, a microfluidic device was developed for visually quantifying pathogenic bacteria in urine without any external equipment. This pioneering strategy has high sensitivity, selectivity and accuracy for rapid detection of Escherichia coli and Staphylococcus aureus simultaneously. It not only shortens the entire test time to 1.5 h, but also successfully reduces the detection limit to 1 CFU/mL, which significantly improves the early diagnosis rate of bacterial infections. Due to the strong affinity of aptamers to target bacteria and the amplification of signals by platinum nanoparticle probes (Pt NP probes) with high catalytic activity, the sensitivity of the device has reached 1 CFU/mL. Moreover, the detection results of UTIs in clinical specimens were consistent with the gold standard, which not only verifies the good accuracy and reliability of the method in such a complex liquid environment, but also implies that the application of the device is paving a new path for biomarker detection and disease diagnosis.
Abstract
This exploratory study was aimed to investigate the link between toxic metal content in women’s urine and their morbidity 2 years before and 6 years after the test. Concentrations of 25 ...metals in urine were analyzed for 111 pregnant women collected prior to delivery. All women were of Arab-Bedouin origin. Information on primary care and hospital visits during the study period was obtained. In a Poisson regression model, a health outcome was regressed over metal exposure and other factors. A Weighted Quantile Sum Regression (WQS) approach was used to indicate metals dominating in their possible impact on women's morbidity. Obesity was the most frequently diagnosed condition in this population (27.9%). Diagnoses in a neurological category accounted for 36.0%, asthma or respiratory—25.2%, psychiatric—12.6%, cardiovascular—14.4% and cancer or benign growth—for 13.5%. Based on WQS analysis, cancer and benign growth were mostly attributed to the increased levels of cadmium, cardiovascular outcomes were linked with lead, and obesity was found associated with elevated levels of nickel. Hematological, neurological and respiratory outcomes were attributed to multiple non-essential metals. The health and exposure profile of women in the study warrants a periodic biomonitoring in attempt to identify and reduce exposure to potentially dangerous elements.
•A miniaturized electrochemical immunosensor for NGAL determination was developed.•The limit of detection of the immunosensor was 0.096 ng mL−1 (0.192 fmol in 50 μL).•The assay consisted in a 125 ...min’ straightforward approach (<10 min hands-on time).•The immunosensor was successfully applied to the determination of NGAL in spiked urine samples.
In this work, a highly sensitive electrochemical immunosensor for the determination of neutrophil gelatinase-associated lipocalin (NGAL) is reported. A miniaturized dual working electrode (WE) screen-printed electrochemical cell was employed as the transducer. The biosensing approach consisted of a sandwich format in which the specific immune-recognition event was detected using alkaline phosphatase as enzymatic label and a 3-indoxyl phosphate/silver mixture as substrate. The analytical signal was based on the voltammetric stripping of the enzymatically deposited silver. The second WE functioned as a negative control. The described methodology achieved a low limit of detection (0.096 ng mL−1; 0.192 fmol in a 50 μL sample) in a 125-min assay (<10 min hands-on time). The applicability of the proposed immunosensor was successfully verified through the analysis of spiked urine samples.
In each sample run, comprehensive two-dimensional gas chromatography with dual secondary columns and detectors (GC × 2GC) provides complementary information in two chromatograms generated by its two ...detectors. For example, a flame ionization detector (FID) produces data that is especially effective for quantification and a mass spectrometer (MS) produces data that is especially useful for chemical-structure elucidation and compound identification. The greater information capacity of two detectors is most useful for difficult analyses, such as metabolomics, but using the joint information offered by the two complex two-dimensional chromatograms requires data fusion. In the case that the second columns are equivalent but flow conditions vary (e.g., related to the operative pressure of their different detectors), data fusion can be accomplished by aligning the chromatographic data and/or chromatographic features such as peaks and retention-time windows. Chromatographic alignment requires a mapping from the retention times of one chromatogram to the retention times of the other chromatogram. This paper considers general issues and experimental performance for global two-dimensional mapping functions to align pairs of GC × 2GC chromatograms. Experimental results for GC × 2GC with FID and MS for metabolomic analyses of human urine samples suggest that low-degree polynomial mapping functions out-perform affine transformation (as measured by root-mean-square residuals for matched peaks) and achieve performance near a lower-bound benchmark of inherent variability. Third-degree polynomials slightly out-performed second-degree polynomials in these results, but second-degree polynomials performed nearly as well and may be preferred for parametric and computational simplicity as well as robustness.
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