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To integrate antifouling properties and good sensitivity on the sensing interface can improve the applicability of an electrochemical immunosensor. These functional regions can be integrated into a single functional peptide (functPP). The rational designed three domains in functPP were the anchoring, antifouling and gold nanoparticles (AuNPs) recognizing domains. Meanwhile, the ordered AuNPs inspired by C 15 H 23 CO-RRRRR can be recognized by AuNPs recognizing domains in functPP to enhance the intensity of detecting current. In the sensing system, the anchoring domain in functPP can be immobilized on the Au electrode by Au S interaction, while the antifouling domain undergoes strong hydration with water molecules to resist matrices, and the recognizing domains can directionally capture O-AuNPs to form a functPP-O-AuNPs complex as the core sensing element. Consequently, the complex bound to the monoclonal antibodies against zearalenone by electrostatic adsorption to develop a highly antifouling and sensitive biosensor with the ability to identify zearalenone in cereals. [Display omitted] • The function of antifouling and AuNPs recognizing were integrated in functPP. • The antifouling part utilizes hydrophilic surfaces to repel nonspecific matrices. • O-AuNPs can improve the electrocatalytic performance by reducing ΔEp. • The present immunosensor could determine ZEN with a low dilution rate. [ABSTRACT FROM AUTHOR]

Pickled bamboo shoots represent a type of fermented bamboo shoot product. In China, pickled bamboo shoots are regarded as the soul of Luosifen, which is a local specialty food in Liuzhou (Guangxi Zhuang Autonomous Region, China). To exemplify the uniqueness of the pickled bamboo shoots, we analyzed the pickled bamboo shoots within 10 pre-packaged Chinese Luosifen to determine the composition of volatiles and bacteria, and subsequently examined the correlation between them. The volatiles were identified using gas chromatography–mass spectrometry (GC–MS) and gas chromatography-ion mobility spectrometry (GC-IMS). Meanwhile, high-throughput sequencing technology was employed to investigate the bacterial composition. The results indicated that the pH values of the samples exhibited minimal variance (ranging from 3.71 to 4.53), while the total acid (measured as g lactic acid /L) varied (from 4.65 to 10.3 g lactic acid /L). Lactic acid, acetic acid, and succinic acid were the predominant organic acids. 50 volatiles were detected by HS-GC-MIS, and 108 volatiles were identified by HS-SPME-GC–MS. p -Cresol (76,541.67 < OAV < 248,166.67), acetic acid (482.31 < OAV < 1164.62), and hexanoic acid (108.33 < OAV < 1333.33) were the common distinctive volatiles among the 10 samples. Proteobacteria and Firmicutes, as the dominant phyla, were positively and negatively related to 1-butanol (R = 0.66, − 0.66), respectively. In China, Luosifen, as a local delicacy, enjoys popularity among the public for its sour, smelly, spicy, fresh, and oily features. Among them, pickled bamboo shoots are highly sought after for their distinctive sour and refreshing flavor. Nevertheless, some individuals cannot tolerate the sour smell of pickled bamboo shoots yet still have a desire to consume Luosifen. To address this issue, it is crucial to determine what constitutes the pungent odor in pickled bamboo shoots and subsequently regulate it to meet the requirements of diverse consumers and enhance the economic benefits of the Luosifen industry. This study disclosed the stimulant flavor substances of pickled bamboo shoots in 10 pre-packaged Luosifen detected by GC–MS and GC-IMS, offering a theoretical foundation for subsequent regulation. [Display omitted] • Volatiles and bacteria composition of pickled bamboo shoots in Luosifen were explored. • HS-GC-MIS detected 50 volatiles, while HS-SPME-GC–MS detected 108 volatiles. • p -Cresol, acetic acid, and hexanoic acid were the characteristic volatiles. • The dominant bacteria in the samples did not include any lactic acid bacteria. [ABSTRACT FROM AUTHOR]

The rise of service robots is changing how products and services are delivered, significantly affecting customer outcomes. However, research has yet to specifically examine how the design of a service robot to specific service contexts influences customer engagement and value co-creation. Our study adopts a contingency perspective to investigate how the design of robot capabilities and personalities aligned with specific service contexts impacts customer engagement and value co-creation intentions. We tested this proposition through three experiments carried out in the banking and restaurant service contexts. Our findings revealed the effectiveness of carefully designed robotic capabilities and personalities within a service infrastructure depends on the specific service contexts. The study findings have important implications for service firms in designing service robots through managing robot capabilities and personalities to align with specific service contexts. • Matching robot capabilities with personalities can improve their effectiveness. • Service contexts can change the effects of robot capabilities and personalities. • Design of robot capabilities and personalities should align with the service context. • Investing in robotic infrastructure can improve business outcomes. • Three experiments were conducted in banking and restaurant service settings. [ABSTRACT FROM AUTHOR]

To increase information content per screen, a dual-wavelength, homologous and high-throughput fluorescence polarization immunoassay (DWFPIA) for simultaneous detection of total aflatoxins (AFs) and family zearalenones (ZENs) was developed. Aflatoxin B 1 (AFB 1 ) and zearalanone (ZAN) were labeled with different fluoresceins, and then combined with corresponding broad-specific antibodies to develop the DWFPIA. Under optimal conditions, the half maximal inhibitory concentrations of the FPIA in buffer were 2.68 μg/L and 4.08 μg/L for total four AFs (the weight ratio of AFB 1 : Aflatoxin B 2 : Aflatoxin G 1 : Aflatoxin G 2 was 1: 1: 1: 1) and six ZEN analogs (the weight ratio of ZEN: ZAN: α-zearalenone: β-zearalenone: α-zearalanone: β-zearalanone was 1: 1: 1: 1: 1: 1) by mixing equal volumes (1: 1, v/v), respectively. The corresponding limit of detection values in maize flour samples were 4.98 μg/kg and 11.03 μg/kg, and the mean recoveries ranged from 78.6 to 103.6% with the coefficients of variation below 19.2%. The whole detection procedure, including sample preparation, took less than 30 min. Finally, the DWFPIA was applied to screen naturally contaminated maize flour samples, and the detection data were similar to those with HPLC-MS/MS. [ABSTRACT FROM AUTHOR]

The molecular mechanisms of T-2 mycotoxin induced neurotoxicity remains enigmatic. In the present study we show that T-2 toxin induced neurotoxicity in mouse neuroblastoma2a (N2a) cells is both dose- and time-dependent and is associated with oxidative stress, mitochondrial dysfunction and apoptosis. T-2 toxin treatment of N2a cells at 10, 20, 40 and 80 ng/mL for 24 h significantly up-regulated the mRNA expression of p53, Bax, and caspase-8 and down-regulated the expression of Nrf2 and HO-1 mRNA and protein expression. Activation of caspases-8, -9 and -3 was also evident in a concentration-dependent manner. Pre-treatment of the cells with the antioxidant N -acetyl-cysteine markedly suppressed T-2 toxin-induced neurotoxicity and caspase activation. Conversely, pre-treatment of the cells with the Nrf2 inhibitor brusatol or the HO-1 inhibitor zinc protoporphyrin IX, enhanced T-2 toxin induced neurotoxicity and increased the activation of caspase-9 and -3. Taken together, these novel findings suggest that T-2 toxin-induced neurotoxicity in N2a cells involves oxidative stress, mitochondrial dysfunction and apoptosis via the inhibition of the Nrf2/HO-1 and activation of p53 pathway. The present study highlights the potential of developing much needed pharmacological interventions to prevent T-2 toxin neurotoxicity. [ABSTRACT FROM AUTHOR]

To investigate whether endometrial thickness (EMT) acts as a contributing factor to adverse perinatal outcomes in programmed frozen-thawed embryo transfer (FET) cycles. Retrospective cohort study. University-based reproductive medical center. The study included singleton live births resulting from programmed FET cycles that took place between January 2017 and April 2022 (N = 2,275 cycles). The EMT measurement conducted on the day of progesterone initiation was utilized. Programmed FET cycles with EMT <7 mm were excluded from consideration. All included subjects were divided into 4 groups on the basis of the 10th, 50th, and 90th percentiles of EMT: group Ⅰ (EMT ≤8 mm, n = 193), group Ⅱ (EMT = 8.1–10 mm, n = 1,261), group Ⅲ (EMT = 10.1–12 mm, n = 615), and group Ⅳ (EMT >12 mm, n = 206). After adjusting for patient demographics and FET parameters, logistic regression analysis and restricted cubic spline were used to investigate the relationship between EMT and perinatal outcomes. The group Ⅱ (EMT = 8.1–10 mm) served as a reference. The primary outcome measure was the hypertensive disorders of pregnancy (HDP). Secondary outcomes included gestational diabetes mellitus, cesarean delivery, placenta previa, premature rupture of membrane, birthweight, preterm birth, low birthweight, macrosomia, small for gestational age, large for gestational age and neonatal morbidity. The incidence of HDP was substantially elevated in group Ⅳ when compared with the other groups (5.7% vs. 4.1% vs. 5.7% vs. 9.7% for groups Ⅰ–Ⅳ, respectively). In addition, group I displayed a higher incidence of cesarean deliveries, whereas both group I and group IV exhibited an elevated prevalence of placenta previa. After adjusting for confounding factors, patients in group IV exhibited a significantly increased risk of HDP (adjusted odds ratio [OR] = 2.03, 95% confidence interval [CI] 1.13–3.67) as compared with patients in the reference group. The restricted cubic spline model revealed a nonlinear association between EMT and the odds of HDP on continuous scales. In comparison to women with an EMT of 9.5 mm, there was no significant change in the risk of HDP in women with EMT between 7 and 11 mm, as indicated by adjusted ORs of 1.37 (95% CI 0.41–4.52), 1.34 (95% CI 0.73–2.47), 1.13 (95% CI 0.79–1.62), 1.04 (95% CI 0.87–1.25), and 1.46 (95% CI 0.81–2.65), respectively. However, the risk of HDP was significantly higher in women with EMT ranging from 12 to 15 mm, with adjusted ORs of 1.86 (95% CI 1.03–3.35), 2.33 (95% CI 1.32–4.12), 2.92 (95% CI 1.52–5.60), and 3.62 (95% CI 1.63–8.04), respectively. This study demonstrated a noteworthy association between EMT and adverse perinatal outcomes during the programmed FET cycles. Specifically, a thick endometrium (EMT >12 mm) was independently associated with an increased risk of developing HDP, whereas the optimal EMT for reducing the risk of HDP was at around 9–10 mm. [ABSTRACT FROM AUTHOR]

An immunoaffinity column (IAC) for the selective purification of 3-methyl-quinoxaline-2-carboxylic acid (MQCA) from porcine muscle and the liver as well as the methods for its determination by high-performance liquid chromatography with ultraviolet detection (HPLC-UV) and a colloidal gold-based immunochromatographic assay (GICA) were developed. This is the first study that describes a clean-up method that employs an IAC for the determination of MQCA. Using the HPLC-UV method, the limits of detection and limits of quantification for MQCA in different samples were 1.0–3.0 μg kg −1 and 4.0–10.0 μg kg −1 , respectively. The average recoveries of MQCA that was spiked into samples at concentrations of 4.0–100 μg kg −1 were 80.1–87.7%, with relative standard deviations of less than 8.5%. Using the GICA method, the limits of detection for MQCA in different samples were 10 μg kg −1 and 50 μg kg −1 . No false negatives or false positives were observed. [ABSTRACT FROM AUTHOR]

To reduce the incidence of false-positive and false-negative results caused by high or low cross-reactivity (CR%) values of the antibodies for total aflatoxins (AFs, AFB 1 +AFB 2 +AFG 1 +AFG 2 ) detection, a new broad-specific monoclonal antibody (MAb) with uniform affinity, named 5H3, was developed. Moreover, magnetic beads (MBs) replaced microplates as immobile phase to improve the sensitivity of the enzymatic immunoassay. Then, a direct competitive enzyme-linked immunosorbent assay (ELISA) based on MBs (MBs-dcELISA) that could simultaneously detect the total AFs with similar sensitivity was developed. Following optimization of conditions, the half maximal inhibitory concentrations (IC 50 ) of the MBs-dcELISA in buffer were 0.05 ng/mL for AFB 1 , 0.04 ng/mL for AFB 2 , 0.05 ng/mL for AFG 1 , 0.06 ng/mL for AFG 2 . The corresponding CR% values were 100%, 125%, 100% and 83.3%, respectively. The limit of detection (LOD) of the MBs-dcELISA for the total AFs was 0.21 ng/g with a working range from 0.22 ng/g to 19.8 ng/g, and the recoveries for the total AFs ranged from 74.5% to 96.5% with coefficients of variation (CV) under 12.1% in spiked maize samples. In addition, the MBs-dcELISA was more sensitive than the conventional dcELISA. Finally, the MBs-dcELISA was applied to screen 9 naturally contaminated maize samples and 6 spiked samples and the results indicated a good agreement with that obtain by HPLC-MS/MS method. [ABSTRACT FROM AUTHOR]

• A novel hapten design strategy focused on atomic charge distribution was proposed. • A high-affinity and specific mAb 8C9 against MQCA was prepared. • A sensitive icELISA for screening MQCA in swine muscle and liver was developed. Production of high-affinity and specific antibodies to small molecules with molecular weight (MW) lower than 200 Da is challenging. Here, we designed a novel hapten, named hapten H6, for the detection of 3-methyl-quinoxaline-2-carboxylic acid (MQCA, MW of 189 Da), a residual marker of olaquindox, one of important veterinary antibiotics. The hapten H6 maintained all structural features of MQCA, especially in mulliken atomic charge distribution. Then, a monoclonal antibody (mAb) named 8C9 was obtained with an IC 50 value of 0.2 µg/L, yielding a 15.5- to 88.5-fold improvement compared to previously prepared specific antibodies against MQCA. In addition, mAb 8C9 exhibited ignorable cross-reactivity with other structural analogs. Finally, a highly sensitive and specific indirect competitive ELISA based on mAb 8C9 was developed for the detection of MQCA in swine muscle and liver samples with limit of detection values of 0.04 µg/kg and 0.09 µg/kg, respectively. [ABSTRACT FROM AUTHOR]

A rapid lateral flow fluorescent microsphere immunochromatographic test strip (FM-ICTS) assay has been developed for the detection of aflatoxin M 1 (AFM 1 ) residues in milk. For this purpose, an ultra-sensitive anti-AFM 1 monoclonal antibody (MAb) 1D3 was prepared and identified. The IC 50 value of the MAb 1D3 for AFM 1 was 23 ng/L, and the cross-reactivity (CR) of the MAb with aflatoxin M 2 , aflatoxin B 1 , aflatoxin B 2 , aflatoxin G 1 and aflatoxin G 2 was 18%, 9%, <0.15%, 43% and <0.3%, respectively. The MAb was covalently conjugated with carboxylate-modified FMs, and the FMs were used as the label in a competitive immunochromatography assay. Using a moderate hapten-to-protein coupling ratio (˜2) in the coating antigen resulted in improved immunoassay sensitivity. Under optimal conditions, the IC 50 value of the assay was 36.3 ng/L with the limit of detection (LOD) of 4.4 ng/L in milk samples using a fluorescence reader, and the recoveries of AFM 1 in spiked milk samples ranged from 76.6 to 110.8% with coefficient of variation (CV) of 4–14.7%. The whole procedure could be completed within 30 min. The results demonstrated that the FM-ICTS assay is easy to conduct, rapid, highly sensitive and specific for the detection of AFM 1 residues in milk. [ABSTRACT FROM AUTHOR]

Objective To determine the effects of Benzo(a)pyrene (BaP) on the development of early preimplantation embryo by exposure to physiologic concentrations of BaP based on a previous report in human ovarian follicular fluid and serum. Design Zygotes were cultured in 5 nM or 50 nM BaP and then examined for development efficiency, embryo quality, and DNA damage. In addition, embryonic stem cells (ESCs) were used as a model to test the toxic effects of BaP on inner cell mass (ICM) of blastocysts. Setting Laboratory. Animal(s) CD1 mice. Intervention(s) Mouse zygotes and ESCs were cultured in medium with 5 nM or 50 nM BaP. Main Outcome Measure(s) The percentage (rate) of blastocyst development, reactive oxygen species level, and quality of embryos assessed by total cell number, cell apoptosis, Oct4- and Nanog-positive cell ratio, and DNA damage on genomic and telomeric DNA were compared between dimethyl sulfoxide control and BaP treatments. Result(s) The BaP-treated zygotes exhibited significantly higher reactive oxygen species activity, which might lead to more cell apoptosis, low ratio of Nanog- or Oct4-positive ICM cells, and increasing DNA damage in both genomic and telomeric DNA in blastocysts. By using mouse ESCs derived from ICM cells as a model, we showed that pluripotent cells might also show serious DNA damage after a brief exposure to BaP. Conclusion(s) Our data show that BaP could seriously disrupt cell growth and genomic DNA stability and increase cell apoptosis in mouse preimplantation embryo development. [ABSTRACT FROM AUTHOR]

The spectral angle mapper (SAM), as a spectral matching method, has been widely used in lithological type identification and mapping using hyperspectral data. The SAM quantifies the spectral similarity between an image pixel spectrum and a reference spectrum with known components. In most existing studies a mean reflectance spectrum has been used as the reference spectrum for a specific lithological class. However, this conventional use of SAM does not take into account the spectral variability, which is an inherent property of many rocks and is further magnified in remote sensing data acquisition process. In this study, two methods of determining reference spectra used in SAM are proposed for the improved lithological mapping. In first method the mean of spectral derivatives was combined with the mean of original spectra, i.e., the mean spectrum and the mean spectral derivative were jointly used in SAM classification, to improve the class separability. The second method is the use of multiple reference spectra in SAM to accommodate the spectral variability. The proposed methods were evaluated in lithological mapping using EO-1 Hyperion hyperspectral data of two arid areas. The spectral variability and separability of the rock types under investigation were also examined and compared using spectral data alone and using both spectral data and first derivatives. The experimental results indicated that spectral variability significantly affected the identification of lithological classes with the conventional SAM method using a mean reference spectrum. The proposed methods achieved significant improvement in the accuracy of lithological mapping, outperforming the conventional use of SAM with a mean spectrum as the reference spectrum, and the matching filtering, a widely used spectral mapping method. [ABSTRACT FROM AUTHOR]

This study synthesized a new alternariol (AOH) hapten. The AOH had an alkylation reaction with ethyl 4-bromobutyrate, followed by hydrolysis and purification, and then conjugated with keyhole limpet hemocyanin to immunize mice and successfully produced two kinds of monoclonal antibodies (mAbs), namely the antibodies which can recognize both AOH and alternariol monomethyl ether (AME) and the ones that can specifically recognize AOH. Wherein, mAb 13D8 can uniformly recognize AOH and AME with the 50% inhibition concentration (IC 50 ) values of 9.4 ng/mL and 9.7 ng/mL, respectively. An indirect competitive ELISA (icELISA) was established by mAb 13D8 to simultaneously detect AOH and AME, with the limit of detection (LOD) being 0.7 ng/mL and 1.0 ng/mL, respectively. The average recoveries in spiked wheat sample were 84.5–107.6% with the coefficient of variation (CV) lower than 10%. The established icELISA method was used to detect 13 real samples with the same results as HPLC-MS/MS, indicating that the method is suitable for simultaneous detection of AOH and AME in wheat. [ABSTRACT FROM AUTHOR]

The use of lignocellulose materials to prepare reinforced composites for 3D printing is promising. In this study, lignocellulose nanofibers (LCNFs) with different lignin contents (0.2–8.5%) were prepared and compounded with polylactic acid (PLA) for fabricating a 3D printable filament. The internal lignin of LCNFs served as an adhesive for improving the interfacial compatibility of LCNF/PLA composites. Alkali lignin (AL), as an external lignin, was used as a control sample. LCNFs, with a high yield of 85%, a diameter of less than 100 nm, and a length of several microns, were prepared by the swelling of glycerol and 0.64% (w/w) sulfuric acid and colloid mill grinding. Complexation of cellulose nanofiber (CNF) and LCNF with PLA can enhance the mechanical strength of PLA composites. Specifically, the flexural strength of the CNF/PLA composite was increased from 92.7 MPa to 151.2 MPa by combining 10% CNF (without lignin) with PLA. The flexural strength of LCNF/PLA composite with internal lignin content of 3.7% (0.37% of the total mass) was increased from 151.2 MPa to 234.5 MPa, which is 153.0% higher than that of pure PLA. However, external AL had an adverse influence on the mechanical strength of the AL/CNF/PLA composites. In addition, the 3D printable filament prepared using the LCNF/PLA composite exhibited good thermal stability, which was suitable for common fused deposition modeling (FDM) 3D printers. Various 3D printing materials, such as cake, egg, ball, bowl, dumbbell and strip shaped products, were designed and prepared by LCNF/PLA composites. • The LCNFs were prepared by slight acid assisted colloid mill grinding treatment. • The yields of as-prepared LCNFs with internal lignin can reached to 85%. • The presence of internal lignin can improve interfacial compatibility of LCNF/PLA. • Addition of LCNFs enhanced the mechanical strength of the LCNF/PLA composites. • Various 3D printing products were prepared using LCNF/PLA composite filaments. [ABSTRACT FROM AUTHOR]

• Morphology control achieved via Zr:Ce and metal-to-ligand ratio adjustments. • Polydopamine-coated tips enhance protein coupling and minimize reagent use. • MOVE immunosensor achieved economical, rapid, and accurate rapid testing. • Enrofloxacin facilitated with one-step reaction and UV–Vis readout. Ensuring the safety of animal-derived foods requires the reliable and swift identification of enrofloxacin residues to monitor the presence of antibiotics. In this regard, we synthesized, tuned, and investigated the optical properties of a bimetallic metal–organic framework (Ce/Zr-UiO 66). The investigation was facilitated by employing a polydopamine-coated pipette tip with high adsorption efficiency, serving as an immunoreactive carrier. Subsequently, an immunofunctionalized variant of Ce/Zr-UiO 66, referred to as Ce/Zr-UiO 66@ Bovine serum albumin-enrofloxacin, was developed as an optical probe for the rapid and sensitive identification of enrofloxacin across a variety of samples. The method can accurately detect enrofloxacin at concentrations as low as 0.12 ng/mL, with a determination time of under 15 min; furthermore, it demonstrates exceptional efficacy when applied to food, environmental, and clinical samples. The implementation of this methodology offers a valuable means for cost-effective, rapid, and on-site enrofloxacin determination. [ABSTRACT FROM AUTHOR]

Maxillofacial bone defect is one of the common symptoms in maxillofacial, which affects the function and aesthetics of maxillofacial region. Periodontal ligament stem cells (PDLSCs) are extensively used in bone tissue engineering. The mechanism that regulates the osteogenic differentiation of PDLSCs remains not fully elucidated. Previous studies demonstrated that l-Caldesmon (l-CALD, or CALD1) might be involved in the osteogenic differentiation of PDLSCs. Here, the mechanism by which CALD1 regulates the osteogenic differentiation of PDLSCs is investigated. The osteogenic differentiation of PDLSCs is enhanced with Cald1 knockdown. Whole transcriptome sequencing (RNA-seq) analysis shows that bone morphogenetic proteins (BMP) signaling pathway and Wingless type (Wnt) pathway have significant change with Cald1 knockdown, and the expressions of Wnt-induced secreted protein 1 (WISP1), BMP2, Smad1/5/9, and p-Smad1/5/9 are significantly upregulated, while Glycogen synthase kinase 3β (GSK3β) and p-GSK3β are downregulated. In addition, subcutaneous implantation in nude mice shows that knockdown of Cald1 enhances the osteogenic differentiation of PDLSCs in vivo. Taken together, this study demonstrates that knockdown of Cald1 enhances the osteogenic differentiation of PDLSCs by BMP and Wnt signaling pathways, and provides a novel approach for subsequent clinical treatment. • CALD1 is involved in regulating the osteogenic differentiation of PDLSCs. • CALD1 regulates the osteogenesis of PDLSCs via BMP and Wnt signaling pathways. • CALD1 plays an important role in bone regeneration, which is of great importance in clinical therapy of bone defect. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Highly specific ssDNA aptamers for SMZ were selected for the first time. • The selected aptamers bind SMZ with affinity in the nanomolar range. • The high specificity of the aptamers was determined by molecular simulation. • An aptasensor was developed which had remarkable specificity and sensitivity. • The aptasensor was used to detect SMZ in milk showing high accuracy and precision. Abstract Antibody-based sensors are the most widely used for screening antibiotic residues in food samples. However, these sensors always suffer from cross-reacting antibiotics which are able to bind the employed antibodies in a manner similar to the target, thus resulting in inaccurate quantification. In this study, we developed a highly specific and sensitive chemiluminescence aptasensor for sulfamethazine (SMZ) by employing the supernormal selectivity of a new selected aptamer. Four SMZ-specific aptamers (K d ranging from 79 to 274 nM) were selected in vitro by MB-SELEX with an intentional counter selection to avoid the recognition other sulfonamides, which is impossible to achieve in the corresponding procedure of antibody production. The binding mechanism of aptamers for SMZ was further analyzed and clarified with molecular simulation and docking. Under optimum conditions, the chemiluminescence aptasensor based on the highest affinity aptamer named SA07 provided a limit of detection of 0.92 ng/mL with negligible cross-reactivity with the 27 tested sulfonamides. The developed aptasensor was applied to milk samples, and achieved good accuracy and precision. These results demonstrated that the integration of an aptamer and chemiluminescence in a sensor platform is a promising method for the sensitive, specific, rapid and accurate detection of antibiotic residues of interest in food samples. [ABSTRACT FROM AUTHOR]

Achieving ordered arrangement of gold nanoparticles (AuNPs) on an electrode can further improve the signal intensity of an electrochemical immunosensor. This ordered AuNPs self-assembly can be inspired by peptide amphiphile (PA). The rational design of hydrophobic chains in PA is a crucial step when the range of hydrophobic alkane chain from 14 to 18 carbons. As arginine (R) can combine specifically with Au surface plane (111), four PAs, i.e., C 15 H 23 CO-RR (C16R2), C 15 H 23 CO-RRR (C16R3), C 15 H 23 CO-RRRR (C16R4), and C 15 H 23 CO-RRRRR (C16R5), in this work are designed to investigate the extent of ordered AuNPs self-assembly. The results indicate that C16R4 presented a dominant electron donating ability and can inspire the self-assembly of AuNPs to form a mono-dispersed raspberry-like structure (C16R4-AuNPs) to obtain the largest ΔI (15.4 μA). In the detection system, C16R4-AuNPs firstly capture and immobilize anti-β-lactam receptor monoclonal antibodies (mAb) by electrostatic adsorption, and the anti-β-lactam receptor mAb possess antigen-antibody binding sites away from the active site of the receptors. Then, they capture β-lactam receptors through an antigen-antibody reaction to form a ternary complex (C16R4-AuNPs-mAb-β-lactam receptors). Based on this indirect-labeling process, the receptor active sites have been exposed completely, facilitating ligand recognition, which greatly further improves the sensitivity of the present method. Finally, a highly sensitive electrochemical immunosensor based on the ternary complex is developed to achieve the determination of 22 β-lactam antibiotics, which is more sensitive and applicable than other reported electrochemical sensors. [ABSTRACT FROM AUTHOR]

Histone deacetylase 6 (HDAC6) is a class IIb histone deacetylase that contains two catalytic domains and a zinc-finger ubiquitin binding domain (ZnF-UBP) domain. The deacetylation function of HDAC6 has been extensively studied with common substrates such as α-tubulin, cortactin, and Hsp90. Apart from its deacetylase activity, HDAC6 ZnF-UBP binds to unanchored ubiquitin of specific sequences and serves as a carrier for transporting aggregated proteins. As a result, aggresomes are formed and protein degradation is facilitated by the autophagy-lysosome pathway. This HDAC6-dependent microtubule transport can be used by cells to assemble and activate inflammasomes, which play a critical role in immune regulation. Even viruses can benefit from the carrier of HDAC6 to assist in uncoating their surfaces during their infection cycle. However, HDAC6 is also capable of blocking virus invasion and replication in a non-enzymatic manner. Given these non-enzymatic functions, HDAC6 is closely associated with various diseases, including neurodegeneration, inflammasome-associated diseases, cancer, and viral infections. Small molecule inhibitors targeting the ubiquitin binding pocket of HDAC6 have been investigated. In this review, we focus on mechanisms in non-enzymatic functions of HDAC6 and discuss the rationality and prospects of therapeutic strategies by intervening the activation of HDAC6 ZnF-UBP in concrete diseases. [Display omitted] • Besides its deacetylase activity, HDAC6's ubiquitin-binding zinc finger domain (ZnF-UBP) enables its non-enzymatic functions. • HDAC6 ZnF-UBP can bind to unanchored ubiquitin, facilitating protein degradation via autophagy-lysosome pathway. • HDAC6 participants in diseases like neurodegeneration, cancer, and viral infections, through its non-enzymatic functions. • This review appeals for the development and application of effective HDAC6 ZnF-UBP inhibitors. [ABSTRACT FROM AUTHOR]

Multi-analyte immunoassays have attracted increasing attention due to their short assay times, low sample consumption, and reduced detection costs per assay. In this work, we describe a homologous and high-throughput multi-wavelength fluorescence polarization immunoassay (MWFPIA) for the multiplexed detection of mycotoxins. Three typical Fusarium mycotoxins, deoxynivalenol (DON), T-2 toxin and fumonisin B 1 (FB 1 ), were labeled with different dyes. Tracers and specific monoclonal antibodies (mAbs) were employed in the MWFPIA to simultaneously detect the three mycotoxins. Under optimal conditions, the limits of detection using MWFPIA were 242.0 μg kg −1 for DON, 17.8 μg kg −1 for T-2 toxin and 331.5 μg kg −1 for FB 1 , providing sufficient sensitivity to meet the action levels of these three contaminants in maize as set by the European Union. The use of a methanol/water (2:3, v/v) mixture for sample pretreatment allowed recoveries ranging from 76.5–106.3%, with coefficients of variation less than 21.7%. The total time of analysis, including sample preparation, was less than 30 min. Twenty naturally contaminated maize samples were tested using MWFPIA and HPLC–MS/MS, with correlation coefficients ( R 2 ) of 0.97 for DON and 0.99 for FB 1 . By changing the targets of interest, homologous MWFPIA, a method with high sensitivity, a simple procedure and a short analysis time, can easily be extended to other chemical contaminants. Thus, MWFPIA represents a versatile strategy for food safety analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • A quantity-based magnetic relaxation sensor (sMRS) for chloramphenicol detection. • Polydopamine was used for signal amplification in sMRS sensor. • The limit of detection of sMRS sensor was increased about 49-fold by polydopamine. • The sensor achieved rapid detection of chloramphenicol about 1.5 h in food matrices. • The sMRS sensor signal readout is highly fast and sensitive. Chloramphenicol is an antibiotic that cause adverse effects in humans. In this work, a novel quantity-based magnetic relaxation switching (sMRS) sensor using polydopamine (PDA) for signal amplification was successfully developed for the rapid and sensitive detection of chloramphenicol in fish samples. We first prepared the conjugation of large magnetic nanoparticles (MNPs) and CAP antigen (MNP-antigen), which performed a competitive immune reaction with chloramphenicol and chloramphenicol antibody. Horseradish peroxidase, that can bind to antibody at the surface of large MNPs, was employed to catalyze the rapid polymerization of dopamine to PDA, which was easily deposited onto the surface of large MNPs. The concentration of chloramphenicol is inversely proportional to the content of HRP after reaction, in other words, it is inversely proportional to the content of PDA. PDA then reacted with 30 nm-diameter amine-functionalized MNPs (NH 2 -MNP 30), the consumption of which resulted in a decrease in the concentration of free NH 2 -MNP 30 particles in solution. After magnetic separation, the remaining free NH 2 -MNP 30 served as the magnetic probe for signal readout. The limit of detection of the sMRS assay for detecting chloramphenicol was 16.6 pg/mL, which was 49-fold lower than MRS sensor without signal amplification. This quantity-based MRS sensor can provide a powerful platform for enabling the rapid and sensitive detection of chloramphenicol in food samples. [ABSTRACT FROM AUTHOR]

Highlights: [•] This paper is the first report of a novel hapten containing a pyrimidinyl moiety. [•] The obtained antibody is the most suitable antibody for the detection of SA residues. [•] The ic-ELISA can serve as an effective screening tool in any routine laboratory. [ABSTRACT FROM AUTHOR]

[Display omitted] • Broad-spectrum mAb coupling with MBs for sample purification was designed. • 2,4-Diaminopyrimidines can be simply and accurately detected using HPLC–UV with LOD of 5 μg/kg. • Capacity of reduced matrix effects of IMB-HPLC-UV was better than that of the SPE-based method. To reduce matrix interference and realize simultaneous detection of multiple homologous compounds (trimethoprim (TMP), diaveridine (DVD), ormetoprim (OMP), baquiloprim (BQP), and aditoprim (ADP) in pig, cattle, chicken, and fish muscles), an immunomagnetic bead (IMB)-based sample purification pretreatment with HPLC–UV was developed. A broad-spectrum monoclonal antibody (mAb, named 14C6) was prepared and conjugated with carboxylic-acid-functionalized magnetic nanoparticles using the active ester method to obtain IMBs for sample purification. The extraction solvent was optimized based on the extraction efficiency. Good linearity was observed for all the five analytes (10–200 μg/kg) with the LOD and LOQ of 5 and 10 μg/kg, respectively. The mean recoveries ranged from 62.5% to 76.9%, while the coefficient of variation was <12.2%. The IMB method afforded greater sample purification and enrichment than those achieved with the SPE column-based conventional method. Hence, the IMB-based sample purification is a useful tool to determine 2,4-diaminopyrimidine residues in edible animal tissues. [ABSTRACT FROM AUTHOR]

• A new SPR method for the determination of MQCA had been reported. • The developed SPR method is the first report for MQCA in animal tissues. • The SPR method can serve as an effective screening tool in any routine laboratory. To monitor the illegal use of olaquindox in animals, a monoclonal antibody-based surface plasmon resonance (SPR) biosensor method has been developed to detect 3-methyl-quinoxaline-2-carboxylic acid, the marker residues of olaquindox, in swine tissues. The limit of detection was 1.4 µg kg−1 in swine muscle and 2.7 µg kg−1 in swine liver, which are lower than the EU recommended concentration (10 µg kg−1). The recoveries were from 82% to 104.6%, with coefficients of variation of less than 12.2%. Good correlations between SPR and HPLC results (r = 0.9806, muscle; r = 0.9698, liver) and between SPR and ic-ELISA results (r = 0.9918, muscle; r = 0.9873, liver) were observed in the affected tissues, which demonstrated the reliability of the SPR method. This method would be a rapid and reliable tool for the screening of the residues of olaquindox in the edible tissues of animals. [ABSTRACT FROM AUTHOR]