Controlled Release of Perillyl Alcohol via pH-Responsive Chitosan-Polypyrrole Nanocarriers.

This work focused on developing CS/PPy, a pH-responsive controlled-release nanocarrier composed of natural polymer, the chitosan (CS), and synthetic polymer, the polypyrrole (PPy). The goal was to evaluate its potential application in controlled release studies of perillyl alcohol (POH). To enhance its properties, CS/PPy was cross-linked with glutaraldehyde, resulting in a new material, CS/PPy/GA.

Compounds Isolated from spp. (Eriocaulaceae) and Their Evaluation in Antimicrobial, Cytotoxic, and Antiviral Assays.

and belong to the Eriocaulaceae family. According to the literature, secondary metabolites isolated in have interesting biological activities. This research aimed to isolate constituents from the capitula of the mentioned species and to evaluate their cytotoxic, antimicrobial, and antiviral activities.

A Self-Assembly Pipette Tip Restricted Access Mesoporous Polypyrrole Solid-Phase Extraction Coupled With Capillary Electrophoresis With Diode Array Detection for the Determination of Enalapril in Urine Samples.

A miniaturized self-assembly pipette tip with restricted access mesoporous polypyrrole solid-phase extraction, combined with capillary electrophoresis with diode array detection (CE-DAD), was developed to rapidly extract and determine enalapril from urine samples. The CE-DAD technique used 50 mmol L phosphate (pH 7) as the background electrolyte, a voltage of 13 kV, a 30 mbar hydrodynamic injection for 4 s, a capillary temperature of 25°C, and a wavelength of 195 nm to achieve a migration time of 6.3 min with satisfactory peak asymmetry and no interfering and/or baseline noise.

Sample Preparation Approaches for Determination of Quinolones in Aqueous Matrixes: Systematic Review.

Quinolones and fluoroquinolones are among the most used antibiotics worldwide. Antibiotic resistance genes can be acquired by human pathogens from ambient microorganisms, which can lead to a treatment failure for bacterial infections. Furthermore, determining the levels of quinolones and fluoroquinolones in aqueous matrixes is crucial for safeguarding both human health and the environment.

Magnetic solid phase extraction based on restricted access molecularly imprinted polymer with dually coated for enantioselective determination of tramadol in human plasma by capillary electrophoresis with ultraviolet detection.

A restricted-access magnetic molecularly imprinted polymer with dually coated of hydrophilic monomer and bovine serum albumin was synthesized, properly characterized by different techniques, and used as adsorbent in Magnetic Solid Phase Extraction (MSPE). Furthermore, a simple and efficient method employing capillary electrophoresis with ultraviolet detection was developed and validated for the enantioselective determination of tramadol (TRM) in human plasma. The optimized conditions were 25 mM phosphate background electrolyte at pH 9.

Chiral Recognition Mechanism of Amlodipine by Capillary Electrophoresis Using Carboxymethyl-β-cyclodextrin: An Experimental and Theoretical Study.

Chiral capillary electrophoresis (CCE) represents an effective technique for enantioselective separations. However, additional techniques may be necessary to determine the enantiomers migration order (EMO) and elucidate the chiral recognition mechanism. This study details the development and optimization of a CCE method for the enantioseparation of amlodipine (AML).

Silver Core Coated with Molecularly Imprinted Polymer as Adsorbent in Pipet-Tip Solid Phase Extraction for Neonicotinoids Determination from Coconut Water.

In this work, we report an innovative adsorbent named Ag-MPS@MIP that has a core@shell structure, i.e., silver nanoparticles modified with 3-methacryloxypropyltrimethoxysilane as the core and molecularly imprinted polymer based on methacrylic acid as its shell.

Enhancing verapamil trace determination from biological matrices by bar adsorptive microextraction.

Verapamil is an L-type calcium channel blocker widely used in the treatment of cardiovascular diseases such as hypertension, angina and arrhythmias, requiring accurate therapeutic monitoring to maintain plasma, urine and saliva concentrations within a safe range. In this context, a novel analytical approach has been proposed to determine verapamil in biological samples, using bar adsorptive microextraction coated with reversed-phase polymers followed by high-performance liquid chromatography with diode array detection. Two adsorbents have been chosen, STRATA-CN and ENVI-18 polymers, showing recoveries from 56.

Polypyrrole as Adsorbent in Magnetic Solid Phase Extraction for Progesterone Determination from Human Plasma.

A straightforward and effective chromatographic method has been created for the analysis of progesterone from human plasma using a composite based on polypyrrole/magnetic nanoparticles in the sample preparation procedure. The quantification of progesterone is necessary due to its importance in human development and fertility. The employed conditions used acetonitrile:ultrapure water (70:30, v/v) as the mobile phase at 1.

Coumarin/β-Cyclodextrin Inclusion Complexes Promote Acceleration and Improvement of Wound Healing.

Coumarins have great pharmacotherapeutic potential, presenting several biological and pharmaceutical applications, like antibiotic, fungicidal, anti-inflammatory, anticancer, anti-HIV, and healing activities, among others. These molecules are practically insoluble in water, and for biological applications, it became necessary to complex them with cyclodextrins (CDs), which influence their bioavailability in the target organism. In this work, we studied two coumarins, and it was possible to conclude that there were structural differences between 4,7-dimethyl-2-chromen-2-one (DMC) and 7-methoxy-4-methyl-2-chromen-2-one (MMC)/β-CD that were solubilized in ethanol, frozen, and lyophilized (FL) and the mechanical mixtures (MM).

Magnetic solid-phase extraction based on restricted-access molecularly imprinted polymers for ultrarapid determination of ractopamine residues from food samples by capillary electrophoresis.

An ultrafast, efficient, and eco-friendly method combining magnetic solid phase extraction and capillary electrophoresis with diode array detection have been developed to determine ractopamine residues in food samples. A restricted access material based on magnetic and mesoporous molecularly imprinted polymer has been properly synthesized and characterized, demonstrating excellent selectivity and high adsorbent capacity. Short-end injection capillary electrophoresis method was optimized: 75 mM triethylamine pH 7 as BGE, -20 kV, 50 mbar by hydrodynamic injection during 8 s, and capillary temperature at 25 °C; reaching ultrafast ractopamine analysis (∼0.

Magnetic and mesoporous molecularly imprinted polymer synthesized by rational computation design: Sample preparation and analysis of ractopamine.

Through density functional theory calculations was studied theoretically the formation process of a magnetic and mesoporous molecularly imprinted polymer for ractopamine (RAC), evaluating the molecular electrostatic potential map, functional monomers, functional monomer / template stoichiometry and crosslink agents. The results revealed that the best conditions for the synthesis were established with acrylic acid as functional monomer in a 1: 4 stoichiometry using acetonitrile as the solvent and ethylene glycol dimethacrylate as crosslink agent. It was observed that nine hydrogen bonds established between the RAC and acrylic acid play a key role on the pre-polymerization complex.

Restricted access polypyrrole employed in pipette-tip solid-phase extraction for determination of nimodipine and nicardipine in breast milk.

A HPLC-UV method for the determination of nimodipine and nicardipine in breast milk using restricted access polypyrrole as an adsorbent in pipette-tip solid-phase extraction (PT-SPE) has been developed. The chromatographic conditions were a C column (150 mm × 4.60 mm, 5 μm) using methanol : acetonitrile : ultrapure water (55 : 30 : 15, v/v/v) at a flow rate of 1.

Short-End Injection Capillary Electrophoresis and Multivariate Analysis for Simultaneous Determination of Heavy Metals in Tea.

An ultra-fast method for the simultaneous determination of heavy metals in Passiflora incarnata tea by capillary electrophoresis (CE) using a short-end injection combined with multivariate analysis was proposed. Separation was conducted by hydrodynamic injection (5 s at 0.5 psi) using the short-end injection procedure in a fused uncoated silica capillary (50 cm total length, 10.

Restricted double access mesoporous polypyrrole as adsorbent in pipette-tip solid phase extraction for simultaneous determination of progesterone, pyriproxyfen, and deltamethrin in chicken eggs.

In this study, two sample preparation techniques were evaluated in the simultaneous determination of three compounds with different physicochemical properties, progesterone, pyriproxyfen, and deltamethrin that may be present in the chicken egg. In this procedure, firstly the restricted double access mesoporous polypyrrole was synthesized, which was evaluated as adsorbent in pipette-tip solid phase extraction and dispersive solid phase extraction. After optimizing the extraction parameters, it was found that pipette-tip solid phase extraction was more efficient and, therefore, it was used in the validation and application of the method.

Molecularly imprinted polymers as a selective sorbent for forensic applications in biological samples-a review.

Molecularly imprinted polymers (MIP) consist of a molecular recognition technology with applicability in different areas, including forensic chemistry. Among the forensic applications, the use of MIP in biological fluid analysis has gained prominence. Biological fluids are complex samples that generally require a pre-treatment to eliminate interfering agents to improve the results of the analyses.

Chiral Capillary Electrokinetic Chromatography: Principle and Applications, Detection and Identification, Design of Experiment, and Exploration of Chiral Recognition Using Molecular Modeling.

This work reviews the literature of chiral capillary electrokinetic chromatography from January 2016 to March 2021. This is done to explore the state-of-the-art approach and recent developments carried out in this field. The separation principle of the technique is described and supported with simple graphical illustrations, showing migration under normal and reversed polarity modes of the separation voltage.

Mesoporous molecularly imprinted polymer core@shell hybrid silica nanoparticles as adsorbent in microextraction by packed sorbent for multiresidue determination of pesticides in apple juice.

In this work, we report the synthesis of a mesoporous molecularly imprinted polymer on the surface of silica nanoparticles (core@mMIP) to be applied as adsorbent in microextraction by packed sorbent (MEPS) for selective determination of pesticides in apple juice. The core@mMIP was properly characterized, showing good adhesion of the polymer to the silica core. The best extraction conditions were: 200 µL of ultrapure water as washing solvent, 150 µL of acetonitrile as eluent, 100 µL of sample at pH 2.

Magnetic molecularly imprinted conducting polymer for determination of praziquantel enantiomers in milk.

A new selective adsorbent based on magnetic molecularly imprinted conducting polymer was firstly synthetized and applied to the magnetic solid phase extraction (MSPE) for the determination of PZQ enantiomers in milk samples. The enantioselective separation was performed on a Chiralpak® IB column using mobile phase composed of ultrapure water : tetrahydrofuran : diethylamine (65 : 35 : 0.05, v/v/v).

Fiber spray ionization mass spectrometry in forensic chemistry: A screening of drugs of abuse and direct determination of cocaine in urine.

Rationale: Ambient mass spectrometry techniques are much required in forensic chemistry to evaluate evidence with low analytical interference, high confidence, and accuracy. However, traditional methodologies, such as paper spray ionization, have been shown to present low sensitivity in the analysis of illicit drugs from biological matrices.

Methods: Fiber spray ionization mass spectrometry (FSI-MS) was developed using a capillary polypropylene (PP) hollow fiber.

Elucidation of the chromatographic enantiomer elution order for praziquantel: An experimental and theoretical assessment.

In this work, we have studied both experimentally and theoretically the praziquantel (PZQ) chiral discrimination. According to the main results, the enantioseparation of PZQ was efficiently optimized by HPLC on the reverse phase from the Chiralpak IB column, which has cellulose tris (3,5-dimethylphenylcarbamate) (CDMPC) as a chiral selector. The thermodynamic and structural parameters obtained via density functional theory (DFT) calculations pointed out the chiral discrimination as well as the enantiomeric elution order of PZQ, thus elucidating the experimental data and validating our proposed method.

Novel [6]-gingerol Triazole Derivatives and their Antiproliferative Potential against Tumor Cells.

Background: Effective cancer treatment is a major public health challenge. The limitations of current therapies and their adverse effects reduce the efficacy of treatment, leading to significant mortality rates worldwide. Moreover, natural product chemistry occupies a prominent role in the search for new treatment alternatives, by contributing a spectrum of chemical structures that may potentially yield new bioactive compounds.

Synthesis of mesoporous magnetic polypyrrole and its application in studies of removal of acidic, neutral, and basic pharmaceuticals from aqueous medium.

As an alternative to traditional adsorbents, mesoporous magnetic polypyrrole (MMPPy) was first used as an adsorbent for the removal of acid, neutral, and basic pharmaceutical compounds considered aqueous pollutants. Ibuprofen (IBU, acid), caffeine (CAF, neutral), and bupropion (BUP, basic) were chosen as adsorbates and applied in adsorption studies. They proved to be pH dependent of the aqueous solution and the best results were found at pH 4 for IBU and CAF and pH 7 for BUP and 60 mg was the optimal amount of adsorbent to be used in the studies.

Development and validation of an experimental and theoretical method for the chiral discrimination of dinotefuran.

Dinotefuran is a low-cost agrochemical considered a highly toxic product. In this sense, there is a need for its constant environmental, biological, and food control, aiming to ensure its use to humans as well as to preserve biodiversity and ecosystems. In the present work, we developed an experimental and theoretical method for dinotefuran chiral discrimination.

Assessment of the Performance of Solid Phase Extraction Based on Pipette Tip Employing a Hybrid Molecularly Imprinted Polymer as an Adsorbent for Enantioselective Determination of Albendazole Sulfoxide.

Herein, an organic-inorganic hybrid molecularly imprinted polymer (MIP) was successfully synthesized with albendazole sulfoxide (ABZSO) as a template and 3-(trimethoxysilyl)propyl methacrylate, a bifunctional group compound, as a single cross-linking agent. In this study, a simple method using HPLC-DAD was developed for the determination of ABZSO enantiomers in human urine using pipette tip-based molecularly imprinted polymer solid phase extraction (PT-MIP-SPE). Enantioseparation with satisfactory retention times (5.