Anchoring Au nanoclusters into coordination polymers: A novel approach toward ATP detection and its application.

Adenosine triphosphate (ATP) is the main source of energy required for all life activities and is used as a biomarker for diseases such as cancer. It is of great significance to design a novel fluorescent probe with favorable performance for monitoring the changes of ATP concentration. Herein, a fluorescence probe named ZnCPs@AuNCs for ATP sensing was designed and fabricated by integrating AuNCs into ZnCPs. The emission intensity of AuNCs was greatly enhanced upon the formation of the ZnCPs@AuNCs nanocomposites, which may be attributed to ZnCPs restricting the molecular motion of AuNCs. Upon the introduction of ATP, the fluorescence intensity at 564 nm of ZnCPs@AuNCs is quenched. According to this phenomenon, a sensitive and reliable ATP sensing platform was established. Moreover, ZnCPs@AuNCs were incorporated into a poly (vinyl alcohol) matrix for the fabrication of fluorescent film, which exhibited solid-state fluorescence. Inspired by the remarkable fluorescent properties of ZnCPs@AuNCs, the fluorescent hydrogel was prepared by mixing ZnCPs@AuNCs with κ-carrageenan, which demonstrated a response to ATP and favorable self-healing ability. This work presents a perspective of ZnCPs@AuNCs in multiple applications such as biosensing, fluorescent film, and hydrogel construction.

Association between mode of delivery and postpartum depression: A systematic review and network meta-analysis.

BACKGROUND: Postpartum depression is one of the most common postpartum diseases, which has an important impact on the interaction between mother, infant, partner and family, as well as the long-term emotional and cognitive development of infants. However, there are still great disagreements on whether the delivery mode will affect the risk of postpartum depression. The purpose of this study is to explore whether the mode of delivery will affect the risk of postpartum depression through the comprehensive network meta-analysis of elective cesarean section, emergency cesarean section, instrumental vaginal delivery and spontaneous vaginal delivery. METHODS: We searched in three electronic databases: PubMed, EMBASE and Cochrane Library. RESULTS: This paper included 43 studies with a total sample size of 1,827,456 participants. Direct meta-analysis showed that the odds ratio of postpartum depression risk was 1.33 (95% confidence interval = [1.21, 1.46]) between cesarean section and vaginal delivery. The odds ratios of high Edinburgh Postpartum Depression Scale score between cesarean section and vaginal delivery in the three postpartum periods (within 2 weeks, within half a year and over half a year) were basically the same. There was no difference between cesarean section and vaginal delivery in the risk of severe postpartum depression at the Edinburgh Postpartum Depression Scale cut-off point ⩾13 (odds ratio = 1.07; 95% confidence interval = [0.99, 1.16]). Network meta-analysis showed that the risk of postpartum depression in the pairwise comparisons emergency cesarean section vs spontaneous vaginal delivery and elective cesarean section vs spontaneous vaginal delivery was odds ratio = 1.53 (95% confidence interval = [1.22, 1.91]) and 1.47 (95% confidence interval = [1.16, 1.86]). CONCLUSION: The mode of delivery has a significant effect on the occurrence of mild postpartum depression. Women who give birth by cesarean section, especially who give birth by emergency cesarean section, are at a higher risk of mild postpartum depression. We should carefully monitor the progress of postpartum mental disorders in women who delivered by cesarean section and make it possible for women to have a quick access to mental healthcare.

Cost-effective synthesis of three-dimensional nitrogen-doped nanostructured carbons with hierarchical architectures from the biomass of sea-tangle for the amperometric determination of ascorbic acid.

In this work, the three-dimensional nitrogen-doped nanostructured carbons with hierarchical architectures (3D-NNCsHAs) with high density of defective sites, high surface area and pluralities of pore size distributions was prepared through the pyrolysis of sea-tangle (Laminaria japonica), an inexpensive, eco-friendly and abundant precursor. Benefitting from their structural uniqueness, a selective and sensitive ascorbic acid (AA) sensor based on 3D-NNCsHAs was developed. Compared to the glassy carbon electrode (GCE) and the carbon nanotubes modified GCE (CNTs/GCE), the 3D-NNCsHAs modified GCE (3D-NNCsHAs/GCE) presents higher performance towards the electrocatalysis and detection of AA, such as lower detection limit (1 µM), wider linear range (10-4410 µM) and lower electrooxidation peak potential (-0.02 V vs. Ag/AgCl). In addition, 3D-NNCsHAs/GCE also exhibits high anti-interference and anti-fouling abilities for AA detection. Particularly, the fabricated 3D-NNCsHAs/GCE is able to determine AA in real samples and the results acquired are satisfactory. Therefore, the 3D-NNCsHAs can be considered as a kind of novel electrode nanomaterial for the fabrication of selective and sensitive AA sensor for the extensive practical applications ranging from food analysis, to pharmaceutical industry and clinical test.

Self-Assembling Glutamate-Functionalized Cyclodextrin Molecular Tube for Specific Enrichment of N-Linked Glycopeptides.

Cyclodextrin molecular tube (CDMT), a new comer of cyclodextrin family, possesses large and hydrophilic outer area and stable structure. Its development and applications remain highly desired, especially in the field of separation and enrichment. Herein, we developed a CDMT-based enrichment platform focusing on the specific capture of glycopeptides. To enhance the hydrophilicity of CDMT, it was functionalized with glutamate (glu). The prepared gluCDMT exhibited large hydrophilic surface, high stability, and good acidic/alkalic resistance. A solid monolithic support was employed to immobilize gluCDMT by a host-guest self-assembly synthetic strategy, which did not occupy the surface hydrophilic sites. The gluCDMT-based monolith exhibited high binding capacity (∼50 mg g-1), good ability to capture glycopeptides (23 HRP glycopeptides and 28 IgG glycopeptides), and high selectivity (horseradish peroxidase/bovine serum albumin = 1:10 000). Moreover, the developed platform was successfully applied to analyze glycopetides in acute myelogenous leukemia cell lysate and human serum samples.

A magnetic hydrazine-functionalized dendrimer embedded with TiO2 as a novel affinity probe for the selective enrichment of low-abundance phosphopeptides from biological samples.

Dendrimers exhibit tunable terminal functionality and bio-friendly nature, making them of being promising materials for applications in the field of separation and enrichment. In this work, we prepared magnetic hydrazide-functionalized poly-amidoamine (PAMAM) dendrimer embedded with TiO2 for the enrichment of phosphopeptides. The novel affinity probe possessed superparamagnetism, realizing its rapid separation from sample solution. Electrostatic attraction and hydrogen bonding existed between PAMAM and phosphopeptides while Lewis acid-base interaction was originated between TiO2 and the targets. The combined synergistic strength of multiple binding interactions contributed to the highly selective enrichment of phosphopeptides. The specificity for the capture of phosphopeptides was reflected in quantities as low as 1:1000 mass ratio of phosphopeptides to non-phosphopeptides. The detection limit of ß-casein digests was low to 0.4 fmol, indicating the high sensitivity of the developed method. Fifteen and four phosphopeptides could be selectively captured from non-fat milk digests and human serum samples, which further confirmed the great potential of the affinity probe in the extraction of low-abundance phosphopeptides from real complex biological samples.

Design of a calix[4]arene-functionalized metal-organic framework probe for highly sensitive and selective monitor of hippuric acid for indexing toluene exposure.

In the present work, a novel metal-organic framework (MOF) fluorescent probe was prepared by post-synthetic modification of MIL-53-NH2(Al) with carboxylatocalix[4]arene (CC[4]A). The introduced CC[4]A could not only enhance the fluorescence performance and the recognition ability of the probe, but also sustain the high stability under UV light and moisture conditions. A method based on the as-synthesized CC[4]A@MIL-53-NH2(Al) probe was established for sensing hippuric acid. The detection limit was determined to be as low as 3.7 µg mL-1. Over the concentration range of 0.005-3 mg mL-1, the calibration curve was obtained with a satisfactory linearity (R2 = 0.993). The method was successfully used for rapid and highly selective direct monitor of hippuric acid in human urine. The sensor had great potential to be used as a simple diagnostic tool for hippuric acid in human urine which is regarded as a biological index of toluene exposure.

Electrochemical sensing platform based on kelp-derived hierarchical meso-macroporous carbons.

In this paper, kelp (Laminaria japonica), as a kind of abundant biomass, is used as the precursor for the preparation of kelp-derived hierarchical meso-macroporous carbons (K-dHMMCs) through the carbonization under nitrogen (N2) atmosphere at high temperature. The K-dHMMCs exhibits the unique structure with high specific surface area of 416.02 m2 g-1, large pore volume of 0.24 cm3 g-1, the hierarchical meso-macroporous size distribution centered at 2, 12 and 82 nm and high density of defective sites, enabling K-dHMMCs attractive for the electrocatalysis. Drop-casting K-dHMMCs on the glassy carbon (GC) surface allows the construction of K-dHMMCs based electrochemical sensing platform, which shows electrocatalytic activities towards many electroactive molecules, such as potassium ferricyanide, nicotinamide adenine dinucleotide (NADH), hydrogen peroxide (H2O2), dopamine (DA), uric acid (UA), ascorbic acid (AA), epinephrine (EP), l-tyrosine (Tyr) and acetaminophen (APAP). Especially, the K-dHMMCs modified GC (K-dHMMCs/GC) electrode exhibits higher sensitivity, wider linear range, and lower detection limit than both carbon nanotubes modified GC (CNTs/GC) and GC electrodes for H2O2 detection, which makes the K-dHMMCs/GC electrode to be able to determine the H2O2 levels in human urine sample and monitor the H2O2 released from human cancer cells. These results demonstrate that K-dHMMCs/GC possesses a great potential for conventional electrochemical sensing applications.

Development of Gd3+-immobilized glutathione-coated magnetic nanoparticles for highly selective enrichment of phosphopeptides.

In this study, we designed a gadolinium-based immobilized metal ion affinity chromatography material for the selective enrichment of phosphopeptides. Gadolinium ion was immobilized on the surface of glutathione-coated magnetic nanoparticles through a facile and effective synthetic route. The adsorbent integrated the advantages of superparamagnetism of Fe3O4 core, good biological compatibility of glutathione, and strong interaction between gadolinium ion and phosphopeptides. It was employed to enrich phosphopeptides from standard protein digests coupled with MALDI-TOF MS. Results demonstrated that the adsorbent possessed high selectivity for phosphopeptides, good reusability and reproducibility. Moreover, the material provided selective enrichment of phosphopeptides from real samples including non-fat milk digests and human serum. The developed method exhibited high sensitivity (detection limit of 10 fmol), showing great potential in the detection of low-abundance phosphopeptides in biological samples.

Design of pH-Responsive Polymer Monolith Based on Cyclodextrin Vesicle for Capture and Release of Myoglobin.

ß-Cyclodextrin vesicles (CDVs) were first introduced into the polymer monolith to prepare a pH-responsive adsorption material and used for capture and release of a cardiac biomarker, myoglobin (Myo). SH-CDV was decorated with adamantane-modified SH-octapeptide to enhance the encapsulation and release rates of Myo. Afterward, SH-CDV was introduced into the polymer monolith via click reaction to produce a pH-responsive monolith. Combining with the mass spectrometry detection, the CDV-based pH-responsive monolith was used for the enrichment of Myo glycopeptides from the mixture of glycopeptides and nonglycoprotein (bovine serum albumin) tryptsin digests reach up to 1:10 000. A limit of detection of 0.1 fmol was obtained for Myo glycopeptides in the blood sample, indicating the high sensitivity of the method. The prepared CDV-based hybrid monolith demonstrated itself to be a promising material for capture of glycoproteins in complex samples, which provides an efficient strategy for the identification and discovery of biomarkers of acute myocardial infarction.

Multilayer Cucurbit[6]uril-Based Magnetic Nanoparticles Prepared by Host-Guest Interaction: Remarkable Adsorbent for Low Density Lipoprotein Removal from Plasma.

Efficient removal of low density lipoprotein (LDL) is a key challenge due to its high level in plasma as a primary risk factor in the pathogenesis of atherosclerotic cardiovascular disease. In this work, a facile synthesis strategy based on host-guest interactions was developed to prepare multilayer cucurbit[6]uril-based magnetic nanoparticles, MNPs-(HA-DAH5 /HA-CB[6]5 ). The compound was employed as a blood purification material for the removal of LDL from plasma because it had good blood compatibility and could be easily separated with an external magnet. The efficient removal of LDL was attributed to the electrostatic interactions between the positive charged apoB-100 domain of LDL and the negative charged adsorbent. Moreover, the prepared material exhibited high recyclability and could release LDL in physiological saline for recyclable use. MNPs-(HA-DAH5 /HA-CB[6]5 ) offered promising perspectives and broad applications in extracorporeal treatment for the removal of LDL.

Anchoring ß-cyclodextrin modified lysine to polymer monolith with biotin: specific capture of plasminogen.

Plasminogen (Plg) is a kind of glycoprotein which plays an important role in cell migration. The determination of Plg content can directly reflect the abnormal manifestation of fibrinolytic system dysfunctions. In the present work, lysine (Lys)-based adsorbents were prepared for the specific capture of Plg through the covalent binding of Lys with a polymer monolithic substrate. Lys was modified with ß-cyclodextrin (ß-CD) via a click reaction and anchored to the substrate with biotin by host-guest interaction. The biotin-Lys-CD based monolithic material was employed for the specific capture of Plg. Combining with mass spectrometry (MS) determinations, the method exhibited a low detection limit of 1.0 fmol with relative standard deviations below 10.0% for Plg. Considering the advantages of simplicity, sensitivity, and high specificity, the developed approach was successfully applied to the determination of Plg in human plasma samples and opened a gallery for testing Plg as a biomarker for the diagnosis of fibrinolytic system dysfunctions.

Immobilization of ß-Cyclodextrin-Conjugated Lactoferrin onto Polymer Monolith for Enrichment of Ga in Metabolic Residues of Ga-Based Anticancer Drugs.

Biological-material-functionalized porous monoliths were prepared with lactoferrin and ß-cyclodextrin via a click reaction. With the monolith as an extraction medium, a method combined with ICP-MS was developed for the determination of total gallium originating from metabolic residues of orally bioavailable gallium complexes with tris(8-quinolinolato)gallium (GaQ3) as a representative. The method exhibited favorable adsorption behaviors for gallium with high selectivity, low detection limit (2 ng L-1), and an enrichment factor of 29-fold with the sample throughput of 30 min-1. The developed approach was validated by the analysis of gallium from GaQ3 metabolic residues in a human cell line. Additionally, the practical applicability of this method was evaluated by the determination of gallium in human blood and urine samples from cancer patients. Results illustrated that the prepared monolith had potential in Ga-based anticancer drug analysis in complex biological samples.

Highly Sensitive and Selective Sensing of Free Bilirubin Using Metal-Organic Frameworks-Based Energy Transfer Process.

Free bilirubin, a key biomarker for jaundice, was detected with a newly designed fluorescent postsynthetically modified metal organic framework (MOF) (UIO-66-PSM) sensor. UiO-66-PSM was prepared based on the aldimine condensation reaction of UiO-66-NH2 with 2,3,4-trihydroxybenzaldehyde. The fluorescence of UIO-66-PSM could be effectively quenched by free bilirubin via a fluorescent resonant energy transfer process, thus achieving its recognition of free bilirubin. It was the first attempt to design a MOF-based fluorescent probe for sensing free bilirubin. The probe exhibited fast response time, low detection limit, wide linear range, and high selectivity toward free bilirubin. The sensing system enabled the monitor of free bilirubin in real human serum. Hence, the reported free bilirubin sensing platform has potential applications for clinical diagnosis of jaundice.

Peanut agglutinin and ß-cyclodextrin functionalized polymer monolith: Microextraction of IgG galactosylation coupled with online MS detection.

A facile online method coupling polymer monolithic microextraction (PMME) with mass spectrometry (MS) was developed for the detection of Immunoglobulin G (IgG) galactosylation glycopeptides. A peanut agglutinin-ß-cyclodextrin (PNA-ß-CD) functionalized poly(hydroxyethyl methylacrylate-ethyleneglycol dimethacrylate) monolith was designed via a click reaction. Thanking to the specificity of PNA-ß-CD for the targets, the material exhibited enhanced enrichment selectivity and extraction efficiency for IgG galactosylation glycopeptides. Under optimal conditions, the developed method gave a linear range of 0.005-5 pmol for IgG glycopeptides with the regression coefficient greater than 0.9990, and the detection limit of IgG galactosylation glycopeptides as low as 0.5 fmol was achieved. The PMME-MS method was applied to IgG galactosylation glycopeptides in real samples including human serum and acute myelogenous leukemia (AML) cell lysate. A series of unique IgG galactosylation glycopeptides were captured by the monolith in the complex samples, indicating satisfactory enrichment ability for IgG galactosylation glycopeptides. The quick and integrated online PMME-MS method exhibited high selectivity for IgG galactosylation, demonstrating its perspectives on the development and broad applications of MS in studying galactosylation proteins regulated biological processes.

Design of a ruthenium(III) immobilized affinity material based on a ß-cyclodextrin-functionalized poly(glycidyl methacrylate-ethylene dimethacrylate) monolith for the enrichment of hippuric acid.

Immobilized metal affinity chromatography has drawn great attention as a widespread separation and purification approach. In this work, ruthenium was firstly introduced into the preparation of immobilized metal affinity chromatography considering its affinity to N,O-donor ligands. A ß-cyclodextrin-functionalized poly(glycidyl methacrylate-ethylene dimethacrylate) monolith was designed and employed as the supporting material in immobilized metal affinity chromatography. Thiosemicarbazide was introduced into the synthesis process, which not only acted as a bridge between ß-cyclodextrin and glycidyl methacrylate, but also chelated with ruthenium because of its mixed hard-soft donor characteristics. The developed monolithic ruthenium(III)-immobilized metal affinity chromatography column was utilized for the adsorption and separation of hippuric acid, a biological indicator of toluene exposure. To achieve high extraction capacity, the parameters affecting the extraction efficiency were investigated with an orthogonal experiment design, L9 (34 ). Under the optimized conditions, the enrichment factor of hippuric acid was 16.7-fold. The method reproducibility was investigated in terms of intra- and interday precisions with relative standard deviations lower than 8.7 and 9.5%, respectively. In addition, ruthenium(III)-immobilized metal affinity chromatography material could be used for up to 80 extractions without an apparent change in extraction recovery.

Highly selective enrichment of phosphopeptides by on-chip indium oxide functionalized magnetic nanoparticles coupled with MALDI-TOF MS.

Selective and efficient preconcentration is indispensable for low concentration of phosphopeptides in phosphorylated protein-related samples prior to MS-based analysis. Herein, an on-chip system coupled magnetic SPE with MALDI-TOF MS was designed. A metal oxide affinity chromatography material, indium oxide, was coated on the surface of Fe3 O4 magnetic nanoparticles to prepare the adsorbent, spatially confined with an applied magnetic field. The adsorbent exhibited high selectivity for phosphopeptides in tryptic digests of the mixture of ß-casein and BSA (1:1000) and the mixture of ß-casein, BSA, and ovalbumin (1:100:100). Thanking to the enrichment ability and specificity for phosphopeptides with the adsorbent, the on-chip magnetic SPE-MALDI-TOF MS approach showed high sensitivity with a low detection limit of 4 fmol. In addition, the developed approach was used to analyze phosphopetides in non-fat milk digests and human serum successfully.

Preparation of a monolith functionalized with zinc oxide nanoparticles and its application in the enrichment of fluoroquinolone antibiotics.

This study describes the enrichment ability of ZnO-modified methacrylic acid-co-ethylene dimethacrylate polymer monoliths as stationary phases for the simultaneous determination of antibiotics (ofloxacin, ciprofloxacin, enoxacin, and pefloxacin) combined with high-performance liquid chromatography. The prepared monolith was characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier-transformed infrared spectroscopy, and thermogravimetric analysis. The polymer monolith microextraction method has been applied to the enrichment of fluoroquinolone antibiotics and satisfactory results were obtained in the analysis of water samples. Compared with the conventional methacrylic acid based monolith, the developed monolith exhibited a higher enrichment capacity because of the introduction of zinc oxide into the preparation process.

Rapid identification of synthetic colorants in food samples by using indium oxide nanoparticle-functionalized porous polymer monolith coupled with HPLC-MS/MS.

A synthetic protocol for the preparation of an indium oxide nanoparticle-functionalized poly(methacrylic acid-glycidyl methacrylate-ethylene dimethacrylate-ethanediamine) monolithic column is reported. Various techniques, including scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and thermal gravimetric analysis-derivative thermogravimetric analysis were employed to characterize the synthesized monolith. The modified monolithic column was coupled with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for determining synthetic colorants in various food samples. Under optimized conditions, good linearity was obtained for all the targets with squared regression coefficients greater than 0.9982. The limits of detection (S/N = 3) for 12 synthetic colorants were in the range of 0.012-2.97 µg kg(-1). The intra-day and inter-day relative standard deviations, ranging from 2.7% to 8.5%, were within the acceptable range. The developed method was successfully applied to the determination of synthetic colorants in food samples (candy, milk, jelly, jam, canned food, juice, and carbonated drink). Target recoveries at different spiked levels ranged from 73.5% to 112.1% with relative standard deviations of less than 10.3%.