Identification and morphological characterization of different types of plastic microparticles.

The knowledge of the polymeric composition of microplastics (MPs) is interesting because offers useful information on the resistance, durability, and degradability of these materials, also allowing progress in the control of this contamination. However, there is currently a lack of reliable standardized methods for the identification, and characterization of the plastic microparticles. This work uses different techniques in a complementary manner for the identification, and characterization of MPs that more frequently are found in the environment.

Selective Extraction of Diazepam and Its Metabolites from Urine Samples by a Molecularly Imprinted Solid-Phase Extraction (MISPE) Method.

In this research, a molecularly imprinted polymer (MIP) was synthesized by precipitation polymerization using oxazepam (OZ) as a template molecule and was subsequently applied as a selective sorbent for the extraction of diazepam (DZP) and its metabolites in urine samples using an SPE cartridge. OZ, temazepam (TZ), nordiazepam (NZ) and DZP were analyzed in the final extracts by high-performance liquid chromatography with diode array detection (HPLC-DAD). The SPE extraction steps were optimized, and the evaluation of an imprinting factor was carried out.

Assessing Matrix Solid-Phase Dispersion Extraction Strategies for Determining Bisphenols and Phthalates in Gilthead Sea Bream Samples.

Microplastics (MPs) and nanoplastics (NPs) are widely spread in the environment, generating significant concern due to their potential impact on environmental health. Marine species usually ingest plastic fragments, mistaking them for food. Many toxic compounds, such as plastic additives that are not chemically bound to the plastic matrix, can be released from MPs and NPs and reach humans via the food chain.

Assessment of Molecularly Imprinted Polymers as Selective Solid-Phase Extraction Sorbents for the Detection of Cloxacillin in Drinking and River Water.

This paper describes a new methodology for carrying out quantitative extraction of cloxacillin from drinking and river water samples using a molecularly imprinted polymer (MIP) as a selective sorbent for solid-phase extraction (MISPE). Several polymers were synthesized via thermal polymerization using cloxacillin as a template, methacrylic acid (MAA) as a functional monomer, ethyleneglycoldimethacrylate (EGDMA) as a cross-linker and different solvents as porogens. Binding characteristics of the adequate molecularly imprinted and non-imprinted (NIP) polymers were evaluated via batch adsorption assays following the Langmuir and Freundlich isotherms and Scatchard assays.

Evaluation of a molecularly imprinted polymer for determination of steroids in goat milk by matrix solid phase dispersion.

A molecularly imprinted polymer-matrix solid-phase dispersion methodology for simultaneous determination of five steroids in goat milk samples was proposed. Factors affecting the extraction recovery such as sample/dispersant ratio and washing and elution solvents were investigated. The molecularly imprinted polymer used as dispersant in the matrix solid-phase dispersion procedure showed high affinity to steroids, and the obtained extracts were sufficiently cleaned to be directly analyzed.

Determination of dipyrone in pharmaceutical preparations based on the chemiluminescent reaction of the quinolinic hydrazide-H2O2-vanadium(IV) system and flow-injection analysis.

A rapid, economic and sensitive chemiluminescent method involving flow-injection analysis was developed for the determination of dipyrone in pharmaceutical preparations. The method is based on the chemiluminescent reaction between quinolinic hydrazide and hydrogen peroxide in a strongly alkaline medium, in which vanadium(IV) acts as a catalyst. Principal chemical and physical variables involved in the flow-injection system were optimized using a modified simplex method.

An optical sensor for the determination of digoxin in serum samples based on a molecularly imprinted polymer membrane.

This paper reports the synthesis and testing of a molecularly imprinted polymer membrane for digoxin analysis. Digoxin-specific bulk polymer was obtained by the UV initiated co-polymerisation of methacrylic acid and ethylene glycol dimethacrylate in acetonitrile as porogen. After extracting the template analyte, the ground polymer particles were mixed with plasticizer polyvinyl chloride to form a MIP membrane.

A MIP-based flow-through fluoroimmunosensor as an alternative to immunosensors for the determination of digoxin in serum samples.

This work reports a comparative study of two automated flow-through fluorosensors for the determination of digoxin in serum samples: an immunosensor with an anti-digoxin polyclonal antibody as the reactive phase permanently immobilised on controlled-pore glass and a sensor with a selective reaction system based on a methacrylic molecularly imprinted polymer (MIP) synthesised by bulk polymerisation. The variables affecting the sensitivity and dynamic range of the sensors (e.g.

Determination of digoxin in serum samples using a flow-through fluorosensor based on a molecularly imprinted polymer.

This work describes the development of a competitive flow-through FIA assay for digoxin using a molecularly imprinted polymer (MIP) as the recognition phase. In previous work, a number of non-covalent imprinted polymers were synthesised by "bulk" polymerisation. The digoxin binding and elution characteristics of these MIPs were then evaluated to obtain a highly selective material for integration into a sensor.