In Vivo Selective Capture and Rapid Identification of Luteolin and Its Metabolites in Rat Livers by Molecularly Imprinted Solid-Phase Microextraction

Needle-Shaped Biosensors for Precision Diagnoses: From Benchtop Development to In Vitro and In Vivo Applications

To achieve the accurate recognition of biomarkers or pathological characteristics within tissues or cells, in situ detection using biosensor technology offers crucial insights into the nature, stage, and progression of diseases, paving the way for enhanced precision in diagnostic approaches and treatment strategies. The implementation of needle-shaped biosensors (N-biosensors) presents a highly promising method for conducting in situ measurements of clinical biomarkers in various organs, such as in the brain or spinal cord. Previous studies have highlighted the excellent performance of different N-biosensor designs in detecting biomarkers from clinical samples in vitro. Recent preclinical in vivo studies have also shown significant progress in the clinical translation of N-biosensor technology for in situ biomarker detection, enabling highly accurate diagnoses for cancer, diabetes, and infectious diseases. This article begins with an overview of current state-of-the-art benchtop N-biosensor designs, discusses their preclinical applications for sensitive diagnoses, and concludes by exploring the challenges and potential avenues for next-generation N-biosensor technology.

Imprinted covalent organic frameworks solid-phase microextraction fiber for in vivo monitoring of acidic per- and polyfluoroalkyl substances in live aloe

Per- and polyfluoroalkyl substances (PFASs) can lead to risks associated with animal and human health through the transfer along food chains. It is confirmed that PFASs can be transported to each part of plants after taken up by the roots. To better elucidate the underlying mechanisms for such exposure, it is highly valuable to develop analytical capabilities for in vivo monitoring of PFASs in live plants. In this work, a novel imprinted covalent organic frameworks (CMIP) solid-phase microextraction coupled with ultra-performance liquid chromatography-tandem mass spectrometry was developed with low limits of detection for six acidic PFASs (0.1-0.3 ng g-1) and used for in vivo monitoring in live aloe. The CMIP coating shows good precision (RSD of intra and inter ≤9.6 % and 10.2 %, respectively) and possesses much higher extraction efficiency than the commercial coatings. After cultivating aloe in soil spiked PFASs, the in vivo assays gave a wealth of information, including steady-state concentrations, translocation factors, elimination rate constants, and half-life of PFASs. The in vivo tracing method for live plants can provide much needed and unique information to evaluate the risk of PFASs, which are very important for the safety of agriculture production.

The beneficial effects of the active components from Maclura tricuspidata fruits in the treatment of diabetes mellitus

Five active compounds, daidzein, luteolin, alpinumisoflavone (AI), 6,8-diprenylgenistein (DG), and warangalone (WA), were identified from the fruits of Maclura tricuspidata via LC-Q/TOF-MS. WA and DG were shown to reverse the high glucose (HG)-induced injury in human umbilical vein endothelial cells (HUVECs), indicating their potential protective effects in alleviating diabetic symptoms. Network pharmacology was conducted to reveal the potential mechanisms of action of the compounds, and Hsp90α (degree: 47), Src (degree: 49), Akt (degree: 69) and p53 (degree: 60) were shown as the core targets related to antidiabetic properties. Further experimental verification suggested that the compounds could enhance phosphorylation of Src and Akt, increase p53 expression act as Hsp90 inhibitors, and protect against HG induced endothelial dysfunction. Our findings will provide a comprehensive understanding of the active substances of M. tricuspidata, which will be helpful for their utilisation.

Rapid screening and in vivo target occupancy quantitative evaluation of xanthine oxidase inhibitors based on drug-target binding kinetics research strategy: A case study of Chrysanthemum morifolium Ramat

Chrysanthemum morifolium Ramat. is a kind of food and drug dual-use traditional Chinese medicine possessing multiple pharmacological and biochemical benefits. In our study, a rapid and high-throughput method based on Surface plasmon resonance (SPR) biosensor technology was developed and verified for screening potential xanthine oxidase (XOD) inhibitors exemplarily in the Chrysanthemum morifolium Ramat. Coupled with ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS), 14 XOD-binders were identified. In the SPR-based biosensor and molecular docking analysis, most compounds exhibited a strong affinity and binding kinetic property (association rate constant, K_on and dissociation rate constant, K_off) for XOD and could be regarded as potential inhibitors. More importantly, to further accurately assess target occupancy of candidate compounds in vivo, a mathematical model was established and verified involving three crucial intrinsic kinetic processes (Pharmacokinetics, Binding kinetic and Target kinetic). Overall, the proposed screening and assessment strategy could be proved an effective theoretical basis for further pharmacodynamic evaluation.

Discovery of potential active ingredients of Er-Zhi-Wan, a famous traditional Chinese formulation, in model rat serum for treating osteoporosis with kidney-yin deficiency by UPLC-Q/TOF-MS and molecular docking

Er-Zhi-Wan (EZW), a classical traditional Chinese formulation, has attracted more and more attention. This study was carried out to analyze the constituents of EZW absorbed into blood and find out the potential active ingredients for treating osteoporosis (OP) with kidney-yin deficiency (KYD). The rat model of OP with KYD was achieved by ovariectomies and using the mixture of thyroxine and reserpine. Then ultra-high performance liquid chromatography coupled with a quadrupole time-of-flight mass spectrometer (UPLC-Q/TOF-MS) combined with statistical analysis was used to analyze the constituents of EZW absorbed into blood and differential components between the normal and OP with KYD rats. Finally, the components identified in OP with KYD rats were docked with targets of OP with KYD found in online databases. The results of molecular docking were adopted to find the potential active ingredients and further verified in vitro experiment. A total of 21 prototype compounds and 69 metabolites were identified in serum. Among them, 63 components in model rats and 50 components in normal rats were summarized, respectively. Most of the identified metabolites in serum of model rats were produced by hydrolysis, oxidation or glucuronidation, while in serum of normal rats were produced by hydrolysis, oxidation and methylation. According to the results of molecular docking, specnuezhenide, salidroside, tyrosol, echinacoside and verbascoside could be classified as potential active ingredients. The activity of salidroside and a metabolite was verified by pharmacodynamics analysis. In summary, UPLC-Q/TOF-MS system was combined with molecular docking to search the potential active ingredients from model rats of OP with KYD, which provided a new idea for the research on the pharmacodynamic material basis of other traditional medicine. Moreover, the result of this study lays the foundation for further study regarding the mechanism of EZW in treating OP with KYD.

Magnetic porous cellulose surface-imprinted polymers synthetized with assistance of deep eutectic solvent for specific recognition and purification of bisphenols

Magnetic porous cellulose molecularly imprinted polymers-based bisphenols have been developed using Fe₃O₄ as the magnetic material, a deep eutectic solvent as the assisted solvent, and N-isopropylacrylamide as the functional monomer. The resulting magnetic porous cellulose molecularly imprinted polymers were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometry, thermal gravimetric analysis, and Brunauer-Emmett-Teller analysis. Moreover, the adsorption properties of the magnetic porous cellulose molecularly imprinted polymers toward bisphenol A, bisphenol F, and bisphenol AF were investigated using static, dynamic, and selective adsorption experiments. The introduction of porous cellulose materials significantly improves the capabilities of the material. The adsorption capacity, mass transfer efficiency, and selectivity of the magnetic porous cellulose molecularly imprinted polymers toward bisphenol A were 5.9, 4.0, and 4.4 times those of traditional molecularly imprinted polymers. Moreover, the adsorption stability of the magnetic porous cellulose molecularly imprinted polymers was investigated under different temperature and pH conditions. The adsorption characteristics of the magnetic porous cellulose molecularly imprinted polymers toward the target molecules were investigated using adsorption isotherm, kinetic, and thermodynamic models. Hydrogen bonding is the main interaction formed between the magnetic porous cellulose molecularly imprinted polymers and the target molecules. Magnetic porous cellulose molecularly imprinted polymers have great application value with excellent stability and reusability. Finally, the combination of the magnetic porous cellulose molecularly imprinted polymers and high-performance liquid chromatography or ultra-performance liquid chromatography-mass spectrometry was successfully used for the purification and detection of bisphenols in milk (1.349 ng/mL bisphenol F and 3.014 ng/mL bisphenol AF), canned fruits (1129 ng/mL bisphenol A, 10.11 ng/mL bisphenol F, and 91.87 ng/mL bisphenol AF), and fish (11.91 ng/mL bisphenol AF) samples. Furthermore, the magnetic porous cellulose molecularly imprinted polymer method is more selective, sensitive, and accurate than the traditional precipitation method.

In Vivo Solid-Phase Microextraction and Applications in Environmental Sciences

Solid-phase microextraction (SPME) is a well-established sample-preparation technique for environmental studies. The application of SPME has extended from the headspace extraction of volatile compounds to the capture of active components in living organisms via the direct immersion of SPME probes into the tissue (in vivo SPME). The development of biocompatible coatings and the availability of different calibration approaches enable the in vivo sampling of exogenous and endogenous compounds from the living plants and animals without the need for tissue collection. In addition, new geometries such as thin-film coatings, needle-trap devices, recession needles, coated tips, and blades have increased the sensitivity and robustness of in vivo sampling. In this paper, we detail the fundamentals of in vivo SPME, including the various extraction modes, coating geometries, calibration methods, and data analysis methods that are commonly employed. We also discuss recent applications of in vivo SPME in environmental studies and in the analysis of pollutants in plant and animal tissues, as well as in human saliva, breath, and skin analysis. As we show, in vivo SPME has tremendous potential for the targeted and untargeted screening of small molecules in living organisms for environmental monitoring applications.

Boronate-modified polyethyleneimine dendrimer as a solid-phase extraction adsorbent for the analysis of luteolin via HPLC

Luteolin (LTL) is a flavonoid containing a cis-diol, which has significant anti-inflammatory, anti-allergic, anti-diabetic, anti-cancer and neuroprotective activities. In this work, a silver modified boric acid affinity polyvinyl imine (PEI) dendritic adsorbent (PPEI-Ag@CPBA) was prepared on polystyrene (PS) for the rapid recognition and selective separation of LTL. A thin layer of polydopamine (PDA) was formed on the surface of the substrate by self-polymerization, and a PDA-coated PS material (PS@PDA) was obtained. PEI with sufficient active amino groups was grafted onto PS@PDA to obtain a PEI-modified material (PS@PDA@PEI), then AgNO3 was reduced with NaBH4, and PS@PDA@PEI was embedded on Ag. Finally, PPEI-Ag@CPBA was obtained through the condensation reaction of PEI with 4-carboxyphenyl boric acid (CPBA). The adsorption conditions were optimized, the optimal pH and the optimum amount of adsorbent were determined, and the maximum adsorption capacity was found to be 2.49 mg g-1. This method has been successfully applied to the selective identification of LTL in peanut shell samples, and provides a practical platform for the detection of LTL in complex substrates.

Review on in vivo profiling of drug metabolites with LC-MS/MS in the past decade

Metabolite profiling is an indispensable part of drug discovery and development, enabling a comprehensive understanding of the drug's metabolic behavior. Liquid chromatography-mass spectrometry facilitates metabolite profiling by reducing sample complexity and providing high sensitivity. This review discusses the in vivo metabolite profiling involving LC-MS/MS and the utilization of QTOF, QQQ mass analyzers with a particular emphasis on a mass filter. Further, a summary of sample extraction procedures in biological matrices such as plasma, urine, feces, serum and hair as in vivo samples are outlined. toward the end, we present 15 case studies in biological matrices and their LC-MS/MS conditions to understand the metabolic disposition.

Extensive metabolism of flavonoids relevant to their potential efficacy on Alzheimer's disease

Alzheimer's disease (AD) is an age-related neurodegenerative disorder, the incidence of which is climbing with ever-growing aged population, but no cure is hitherto available. The epidemiological studies unveiled that chronic intake of flavonoids was negatively associated with AD risk. Flavonoids, a family of natural polyphenols widely distributed in human daily diets, were readily conjugated by phase II drug metabolizing enzymes after absorption in vivo, and glucuronidation could occur in 1 min following intravenous administration. Recently, as many as 191 metabolites were obtained after intragastric administration of a single flavonoid, indicating that other bioactive metabolites, besides conjugates, might be formed and account for the contradiction between efficacy of flavonoids in human or animal models and low systematic exposure of flavonoid glycosides or aglycones. In this review, metabolism of complete 68 flavonoid monomers potential for AD treatment, grouped in flavonoid O-glycosides, flavonoid aglycones, flavonoid C-glycosides, flavonoid dimers, flavonolignans and prenylated flavonoids according to their common structural elements, respectively, has been systematically retrospected, summarized and discussed, including their unequivocally identified metabolites, metabolic interconversions, metabolic locations, metabolic sites (regio- or stereo-selectivity), primarily involved metabolic enzymes or intestinal bacteria, and interspecies correlations or differences in metabolism, and their bioactive metabolites and the underlying mechanism to reverse AD pathology were also reviewed, providing whole perspective about advances on extensive metabolism of diverse potent flavonoids in vivo and in vitro up to date and aiming at elucidation of mechanism of actions of flavonoids on AD or other central nervous system (CNS) disorders.

Molecularly imprinted polymers in biological applications

Molecularly imprinted polymers (MIPs) are currently widely used and further developed for biological applications. The MIP synthesis procedure is a key process, and a wide variety of protocols exist. The templates that are used for imprinting vary from the smallest glycosylated glycan structures or even amino acids to whole proteins or bacteria. The low cost, quick preparation, stability and reproducibility have been highlighted as advantages of MIPs. The biological applications utilizing MIPs discussed here include enzyme-linked assays, sensors, in vivo applications, drug delivery, cancer diagnostics and more. Indeed, there are numerous examples of how MIPs can be used as recognition elements similar to natural antibodies.

Recent Advances in In Vivo SPME Sampling

In vivo solid-phase microextraction (SPME) has been recently proposed for the extraction, clean-up and preconcentration of analytes of biological and clinical concern. Bioanalysis can be performed by sampling exo- or endogenous compounds directly in living organisms with minimum invasiveness. In this context, innovative and miniaturized devices characterized by both commercial and lab-made coatings for in vivo SPME tissue sampling have been proposed, thus assessing the feasibility of this technique for biomarker discovery, metabolomics studies or for evaluating the environmental conditions to which organisms can be exposed. Finally, the possibility of directly interfacing SPME to mass spectrometers represents a valuable tool for the rapid quali- and quantitative analysis of complex matrices. This review article provides a survey of in vivo SPME applications focusing on the extraction of tissues, cells and simple organisms. This survey will attempt to cover the state-of- the-art from 2014 up to 2019.

Thermoregulated extraction of luteolin under neutral conditions using oligo(ethylene glycol)-based magnetic nanoparticles with Wulff-type boronate affinity

Oligo(ethylene glycol)-based thermoresponsive polymers with Wulff-type boronate affinity were anchored on magnetic nanoparticles. The resultant magnetic nanoparticles were used as sorbents for extracting luteolin, a cis-diol-containing model analyte. By exploiting the thermoresponsive properties and Wulff-type boronate affinity of the sorbents, target adsorption at room temperature (25 °C) and target release at high temperature (40 °C) were achieved under neutral conditions without pH alteration. The proposed thermoregulated extraction method was favorable for automated boronate affinity extraction, preventing degradation of the target and avoiding acidic elution for breaking Wulff-type boronate sites. Compared to reported sorbents for extracting luteolin, the sorbents possessed higher maximum adsorption capacity (98.7 mg g^-1) with acceptable sensitivity, simplified operation procedure, and mild extraction condition. Furthermore, the sorbents were applied in thermoregulated extraction of luteolin from honey samples. Satisfactory recoveries in the range of 83.2% - 89.1% with RSD ranging from 2.2% to 4.6% were achieved. The results demonstrated that this work provided a new research direction to design and synthesize efficient thermoresponsive materials for recognition and release of cis-diol compounds under neutral conditions.

Molecularly imprinted sol-gel polymers for the analysis of iprodione fungicide in wine: Synthesis in green solvent

Iprodione is a fungicide widely used in viticulture in most agricultural countries. It was banned recently in the European community because of its carcinogenic and endocrine disrupting characters. In this work, a cheap analytical method able to monitor iprodione in a white wine was developed. Molecularly imprinted sol-gel polymers (MIS) specific to iprodione and using green solvents were synthesized. An experimental design having the following factors (solvent volume and crosslinker quantity) was used to prepare an optimal MIS. In terms of selectivity, the optimal MIS showed the best partition coefficient towards iprodione in a white wine containing four other competing fungicides (procymidone, pyrimethanil, azoxystrobin and iprovalicarb). A solid phase extraction method using the optimal MIS was optimized and applied to analyse iprodione in a white wine. Low detection and quantification limits were reached 11.7 and 39.1 µg/L respectively.

Current direction and advances in analytical sample extraction techniques for drugs with special emphasis on bioanalysis

Analytical techniques may not be compatible or sufficiently sensitive to the analytes, unless it undergoes a specific sample extraction procedure. Sample extraction can be considered as one of the key steps in analysis. Analysis of a poorly treated sample may produce inferior quality of analytical data. Continuous advancement and development of newer sample extraction techniques such as solid phase microextraction, ultrasound, magnetically and microwave assisted magnetic extraction; electro-membrane extraction and dried blood spotting are to address the shortcomings of the existing techniques and to provide more automation, minimizing preparation time and make them high throughput. This review summarizes the suitability of application of the advanced sample preparation techniques available for chemical and bioanalysis in a comprehensive manner. This review also provides a scientific guidance for selecting the appropriate sample extraction technique based on sample type.

Personalized Medicine for Crops? Opportunities for the Application of Molecular Recognition in Agriculture

This perspective examines the detection of rhizosphere biomarkers, namely, root exudates and microbial metabolites, using molecular recognition elements, such as molecularly imprinted polymers, antibodies, and aptamers. Tracking these compounds in the rhizosphere could provide valuable insight into the status of the crop and soil in a highly localized way. The outlook and potential impact of the combination of molecular recognition and other innovations, such as nanotechnology and precision agriculture, and the comparison to advances in personalized medicine are considered.

Preparation and application of chlorpyrifos molecularly imprinted solid-phase microextraction probes for the residual determination of organophosphorous pesticides in fresh and dry foods

A solid-phase microextraction probe was prepared on the surface of a stainless-steel wire through molecular sol-gel imprinting technology using chlorpyrifos as a template molecule, tetraethoxysilane as a sol-gel precursor, and acrylamide and β-cyclodextrin as functional monomers. The polymer was characterized by infrared spectrometry and scanning electron microscopy. Moreover, the selectivity and the parameters including the type and volume of the extraction solvents, ionic strength, pH, temperature, extraction time, stirring speed, and desorption time affecting extraction performance were evaluated. Under the optimum solid-phase microextraction and gas chromatography conditions, the linear ranges were 0.25-25.0 μg/L for chlorpyrifos, quinalphos, triazophos, pirimiphos-methyl, and chlorpyrifos-methyl with the correlation coefficient above 0.99. The detection limits (S/N = 3) were in the range of 0.02-0.07 μg/L and the RSDs were <7.3%. The developed method was successfully used to determine the multi-residues of chlorpyrifos, quinalphos, triazophos, pirimiphos-methyl, and chlorpyrifos-methyl in green peppers and cinnamon with satisfactory recoveries.

Rapid Colorimetric Detection of Cartap Residues by AgNP Sensor with Magnetic Molecularly Imprinted Microspheres as Recognition Elements

The overuse of cartap in tea tree leads to hazardous residues threatening human health. A colorimetric determination was established to detect cartap residues in tea beverages by silver nanoparticles (AgNP) sensor with magnetic molecularly imprinted polymeric microspheres (Fe₃O₄@mSiO₂@MIPs) as recognition elements. Using Fe₃O₄ as supporting core, mesoporous SiO₂ as intermediate shell, methylacrylic acid as functional monomer, and cartap as template, Fe₃O₄@mSiO₂@MIPs were prepared to selectively and magnetically separate cartap from tea solution before colorimetric determination by AgNP sensors. The core-shell Fe₃O₄@mSiO₂@MIPs were also characterized by FT-IR, TEM, VSM, and experimental adsorption. The Fe₃O₄@mSiO₂@MIPs could be rapidly separated by an external magnet in 10 s with good reusability (maintained 95.2% through 10 cycles). The adsorption process of cartap on Fe₃O₄@mSiO₂@MIPs conformed to Langmuir adsorption isotherm with maximum adsorption capacity at 0.257 mmol/g and short equilibrium time of 30 min at 298 K. The AgNP colorimetric method semi-quantified cartap ≥5 mg/L by naked eye and quantified cartap 0.1–5 mg/L with LOD 0.01 mg/L by UV-vis spectroscopy. The AgNP colorimetric detection after pretreatment with Fe₃O₄@mSiO₂@MIPs could be successfully utilized to recognize and detect cartap residues in tea beverages.

Molecularly imprinted electrospun nanofibers for adsorption of 2,4-dinitrotoluene in water

2,4-Dinitrotoluene molecularly imprinted nanofibers fabricated by a simple electrospinning technique show higher adsorption capacity and possess remarkable stability and reusability.