查看更多>>摘要：We report, for the first time, the application of fluorinated hexagonal boron nitride nanosheets (F-BNNs) as an effective inorganic matrix for matrix-assisted laser desorption and ionization mass spectrometry (MALDI-MS) analysis of perfluoroalkyl acids (PFAAs). Fluoride modification of F-BNNs increases both enrichment ability and ionization efficiency. The method was validated using environmental water, milk, human serum samples, and zebrafish imaging that has been previously exposed to PFAAs. The method provided in this work holds considerable promise in term of rapid analysis, sample requirement, and practicability.
查看更多>>摘要：Despite the tremendous interest for nanoparticles (NPs) in the biomedical field, their transfer to the clinics is still hampered, in particular due to the lack of knowledge of their behaviour in a biological environment. Indeed, the protein corona formed as soon as NPs enter the bloodstream can drastically affect their properties. The use of Taylor dispersion analysis-ICP-MS as an efficient technique dedicated to metal-containing NPs was proposed to examine these NP-protein interactions and determine protein corona thicknesses in biological fluids. This method was applied on core-shell gold/silica NPs in the presence of proteins at high concentrations and serum. Protein corona around 4 nm were measured. Moreover, the versatility of the method allowed assessing the reversible/irreversible character of the interactions.
查看更多>>摘要：Sialylation plays a vital role in multiple different physiologic processes, aberrant sialylation is highly related to disease development. Especially in cancer development, changed states of specific cell-surface sialylation implies rich cancer-related information. Therefore, it is necessary to image specific cell-surface sialylation for better understanding biological functions of sialylation. To meet this purpose, we designed a DNA dendrimer-assisted fluorescence resonance energy transfer (FRET) strategy in this work. By labeling multiple FRET donors and acceptors on the target molecules through metabolic oligosaccharide engineering (MOE) and targeted recognition of aptamer-tethered DNA dendrimer, the FRET was significantly improved. With the DNA dendrimer-assisted FRET strategy, specific imaging of cell-surface sialylation on SMMC-7721 and CEM cells were successfully achieved. The obtained FRET signal intensity was approximately four times higher than the control without the assistance of DNA dendrimer. Moreover, this method is competent to monitor changed states of PTK7-specific sialylation induced by tunicamycin. The proposed imaging strategy may provide a powerful tool to explore the physiological roles of specific cell-surface sialylation and the related mechanism of diseases.
查看更多>>摘要：Chemical vapor or hydride generation (CVG/HG) still plays a significant role in continuous flow sample introduction system. The development and higher accessibility of new commercial CVG/HG accessories (especially modified spray chambers and nebulizers) improves the analytical possibilities of plasma-based optical emission spectrometry for determination of hydride forming analytes. These systems are still designed and widely applied despite the better availability of its alternatives. The commercialization of the first nitrogen microwave induced plasma optical emission spectrometry instrument (MIP OES) also contributes to the increase in popularity of these solutions. The latest achievements in commercial and laboratory-made generators and instruments, as well as new strategies in sample preparation for total content and speciation analysis, are discussed in the review.
查看更多>>摘要：Metallodrug delivery using magnetic nanomaterials is emerging as a tool for the treatment of cancer because of its potential of enhanced and controlled delivery to a specific site within the body, reduced side effects, and protection of drugs from the extracellular environment. In this brief review, we discuss recent progress in the development of iron oxide nanoparticles loaded with platinum anticancer drugs due to applying modern analytical techniques. Such techniques may vary depending on what step of manufacture and assessment of magnetic nanocarriers is in question, i.e., drug loading, payload stability, magnetic properties, drug release or the efficiency against different cancer cell lines. While focusing on a wider implementation of advanced analytical methodologies, we also critically contemplate how they help create more potent magnetic nanoformulations, resolve the current challenges with the use of magnetic nanomaterials in smart metallodrug delivery and thus accelerate their translation to human treatments.
查看更多>>摘要：Recently, using nanomaterials to enhance the endocytosis capability and sensitivity of probes for RNA imaging in living cells has gotten the attention of many researchers. Nanomaterials, as a reliable alternative to transfection reagents, could prevent nucleic acid probes from being degraded by DNase, and bring them into sub-cellular locations for efficient internalization. Therefore, nanomaterial-based fluorescent probes (NFPs) provide a promising sensing platform to realize in situ RNA detection and imaging, which can reveal the expression of RNA at single cell level and provide large amount of information about RNA spatial localization. Meanwhile, many RNAs are in low abundance in living cells, resulting in difficulty in sensitive detection. Thus, the incorporation of NFPs and signal amplification strategy offers a broader prospect for the detection of RNAs, that have been proven as predominant therapeutic targets or diagnostic biomarkers. Herein, the purpose of our review is to first introduce the general procedure of NFPs used for in situ RNA imaging and how nanomaterials deliver these probes into living cells. Further, we focused on different kinds of nanomaterials that are mainly used for sensitive detection of RNAs and those in low abundance, through different signal read-out modes.
查看更多>>摘要：This paper proposes feature vector generation based on signal fragmentation equipped with a model interpretation module to enhance glucose quantification from absorption spectroscopy signals. For this purpose, near-infrared (NIR) and mid-infrared (MIR) spectra collected from experimental samples of varying glucose concentrations are scrutinised. Initially, a given spectrum is optimally dissected into several fragments. A base-learner then studies the obtained fragments individually to estimate the reference glucose concentration from each fragment. Subsequently, the resultant estimates from all fragments are stacked, forming a feature vector for the original spectrum. Afterwards, a meta-learner studies the generated feature vector to yield a final estimation of the reference glucose concentration pertaining to the entire original spectrum. The reliability of the proposed approach is reviewed under a set of circumstances encompassing modelling upon NIR or MIR signals alone and combinations of NIR and MIR signals at different fusion levels. In addition, the compatibility of the proposed approach with an underlying preprocessing technique in spectroscopy is assessed. The results obtained substantiate the utility of incorporating the designed feature vector generator into standard benchmarked modelling procedures under all considered scenarios. Finally, to promote the transparency and adoption of the propositions, SHapley additive exPlanations (SHAP) is leveraged to interpret the quantification outcomes.
查看更多>>摘要：Hydrogen peroxide (H2O2)-involved metabolites are widely engaged in cellular metabolism, and play significant roles in cell proliferation, cell growth, and signaling transduction. It is highly desirable to establish a method for the detection of H2O2-involved metabolites for applications ranging from chemical sensing to biomedical diagnosis. Herein, monodispersed sandwich Au@4-MBN@Ag@PEG nanorods (referred to as AMPRs) with bright Raman emission were developed to serve as a universal platform for detecting H2O2-involved metabolites (4-mercaptobenzonitrile is abbreviated to 4-MBN as the Raman reporter and PEG is polyethylene glycol). The system detects metabolites through changes in the surface-enhanced Raman scattering (SERS) spectrum, resulting from the controllable etching of the silver layer by the H2O2 produced by the metabolites. The inte-grative nanoplatform was successfully used to quantify the levels of glucose, lactate, and choline in aqueous solutions by exploiting the close linear relationship between the intensity of a SERS band and the logarithmic concentration of H2O2. The presented SERS nanoplatform demonstrated considerable practicability for the detection of glucose in cerebrospinal fluid samples (with a limit of detection (LOD) of 1.76 mu M), and was capable of distinguishing infected from uninfected individuals. Therefore, the SERS sensor provides a new platform for the detection of H2O2-involved metabolites in biological fluids, and has potential for use in metabolite analysis and biomedical diagnostics.
Pereira, Carla F.Frasco, Manuela F.Sales, M. Goreti F.
9页
查看更多>>摘要：Accurate and timely diagnosis of venous thromboembolism (VTE) is crucial to prevent related morbidity and mortality. This work reports a label-free sensor for D-dimer, a biomarker of VTE. The sensor is based on the synergy between the colloidal crystal templating method and the molecular imprinting technique. The design of the photonic molecularly imprinted polymer (PMIP) is focused on the preparation of an inverse opal structure, resulting from silica infiltration in a poly(methyl methacrylate) photonic crystal template, followed by a calcination stage that removes the sacrificial colloidal crystal. The molecularly imprinted polymer in the inverse opal structure is then synthesized in the presence of the template molecule, the peptide D-dimer. After D-Dimer removal, the PMIP consists in a three-dimensional highly ordered structure, where nanocavities complementary to the D-dimer in shape and binding features are distributed. The PMIP showed a linear response to D-dimer in synthetic urine, exhibiting a decrease in the reflectance intensity with increasing D-dimer concentrations, ranging from 22.5 ng mL(-1) to 1450.0 ng mL(-1). The PMIP material demonstrated a limit of detection of 15.5 ng mL(-1) and was selective for D-dimer in the presence of fibrinopeptide B, another prospective VTE biomarker in urine. Moreover, the sensor was reusable up to five times without losing its recognition ability. Overall, a novel PMIP material is described for successful recognition of D-Dimer. Considering the clinical relevance of D-dimer detection, the sensor is envisioned as a promising low-cost test for urinalysis.
查看更多>>摘要：The detection of cancer markers still has shortages of low sensitivity, time-consuming operation, the use of unstable and expensive antibodies. In this work, a novel Love-mode surface acoustic wave (LSAW) aptasensor with dummy fingers based on the monolayer molybdenum disulfide/gold nanoparticles (monolayer MoS2/Au NPs) was developed for the highly sensitive and rapid determination of alpha-fetoprotein (AFP) in serum. Interdigital electrodes (IDTs) with dummy fingers were designed and applied to improve the acoustic characteristic of the LSAW aptasensor. The less energy dissipation and wave-front distortion of the LSAW aptasensor were confirmed by COMSOL simulation and test results. The newly-developed sensing film monolayer MoS2/Au NPs/Apt/6-mercaptohexanol (MCH) was applied for the specific detection of AFP and significantly improved the sensitivity of the LSAW aptasensor. The excellent performance of the LSAW aptasensor allowed the sensitive and rapid detection of AFP in serum in the range of 0.01 ? 100 ng/mL with a low detection limit of 4.79 pg/mL. Additionally, the proposed LSAW aptasensor exhibited excellent selectivity, long-term stability, and reproducibility, and could be used to detect other cancer biomarkers.
NSTL
Elsevier