Conductive Polymer-Based Nanocomposites as Powerful Sorbents: Design, Preparation and Extraction Applications.

Conductive polymers as composite materials have been attracted tremendous attention due to their versatile and excellent features such as tunable conductivity, facile synthesis and fabrication, high chemical and thermal stability etc. These characteristics make them versatile and let them being used in numerous fields including microelectronics, optics and biosensors. Throughout the mentioned fields, conductive polymers particularly perform as effective sorbents. Although tremendous efforts have been put into this topic, to the best of our knowledge, a comprehensive up-to-date review on the applications of conductive polymers as efficient sorbents has not been reported. The main objective of this paper is to make a significant contribution to the recent literature toward the synthesis and extraction applications of conductive polymers as efficient sorbents.

Environmental impacts of post-consumer plastic wastes: Treatment technologies towards eco-sustainability and circular economy.

The huge amounts of plastic production (millions of tons) are carried out all around world every year and EU is one of the biggest consumers of these products. In 2021, recycling rate of plastic wastes around 32.5% in the EU and the rest end up on their journey in landfills and oceans that lead to environmental pollution which is a crucial global concern. Thus, it is important to take necessary steps to control the use of such plastic and to sustainably dispose them. One of the solutions to the problem is to use a better alternative to plastics which doesn't degrade land, water or air nor affects living organisms. Circular economy is another answer to this problem, it would ensure prevention of post-consumer plastic waste from getting formed. In addition, sustainable disposal approaches for plastic waste such as pyrolysis, plasma gasification, photocatalytic degradation, and production of value-added products from polymer waste can be explored. These recycling methods has huge potential for research and studies and can play a crucial in eliminating post-consumer plastic waste. This review paper aims to discuss the environmental effects of post-consumer plastic wastes as well as the emerging approaches for the treatment of these environmental wastes towards eco-sustainability and circular economy.

Greenness of lab-on-a-chip devices for analytical processes: Advances & future prospects.

Lab-on-a-chip devices have now-a-days become an important aspect of analytical/bioanalytical chemistry having wide range of applications including clinical diagnosis, drug screening, cell biology, environmental monitoring, food safety analysis etc. Conventional lab-on-a-chip devices generally employ chemicals that are not environmentally friendly and were commonly fabricated on hard plastic platform which are non-degradable and hence ignore the importance of green analytical chemistry. In today's scenario, it is highly imperative to protect our environment by using less toxic and environmentally friendly chemicals/solvents and biocompatible platforms. Accordingly, the present article comprehensively reviews on the various green aspects of lab-on-a-chip devices for analytical processes which aim at fabricating environmentally friendly and cost-effective downsized devices so that the risk factor at the user's end upon longer exposure as well as to the environment can be reduced. The decisive factors for the accomplishment of green aspects of lab-on-a-chip devices including sample preparation using lab-on-a-chip systems to minimize the amount of sample/solvents to few microliters only, substitution of harmful solvents with green alternatives, minimal waste generation or proper treatment of waste and biodegradable and biocompatible platforms for fabricating lab-on-a-chip devices have been discussed in details. Additionally, the challenges that may hinder their commercialization are also critically discussed.

Nano-sized magnetic core-shell and bulk molecularly imprinted polymers for selective extraction of amiodarone from human plasma.

Bulk and magnetic core-shell Molecularly Imprinted Polymers (MMIPs) have been introduced and compared to extract and determine amiodarone from a complex matrix, i.e., plasma, due to the importance of Therapeutic Drug Monitoring (TDM). Polymer synthesis was confirmed by FTIR, AFM, TGA, DLS, VSM, TEM, and the adsorption studies such as capacity, isothermal models, selectivity, and regeneration were performed to evaluate and compare polymer efficiency in extraction and separation of amiodarone from sample solutions and human plasma. Both nano-sized and bulk polymers successfully extracted the target molecule at the low therapeutic ranges and the overdose concentrations (recoveries of 98.38%-102.70%). The maximum adsorption capacity of the MMIPs was 42.5 µg/mg compared with 2.6 µg/mg for bulk polymers. The imprinting factors of the polymers were 15.12 and 6.84 for MMIPs and bulk, respectively. MMIPs and bulk polymers presented 4.68 and 1.66 selectivity factors, respectively, towards amiodarone compared with lidocaine. LOD, LOQ, and enrichment factor in human plasma were 0.09, 0.28 µg mL-1, and 10 respectively. Recoveries of therapeutic concentration from plasma were 91.38 and 97.33% for bulk and MMIPs, respectively. MMIPs as an adsorbent in amiodarone extraction from plasma offered reduced necessary sample amount, less adsorbent consumption, reduced pretreatment time, and reduced elution solvent waste while yielding higher extraction recovery and more specificity for the target compared with the bulk polymer. Bulk polymers have a more straightforward synthesis procedure due to fewer synthesis steps and fewer variables, and Molecularly Imprinted Polymer Solid-phase Extraction (MIP-SPE) has already been introduced commercially. MMIPs prevail on a small scale, and in the context of a simple extraction, separation, or concentration in large-scale bioanalysis, efforts towards optimization and development of MMIPs can unearth tremendous opportunities for green chemistry principles.

Controllable Synthesis of Polymeric Micelles by Microfluidic Platforms for Biomedical Applications: A Systematic Review.

Polymeric micelles (PMs) are one of Nanoscale delivery systems with high stability, loading capacity, and biocompatibility. PMs are nano-sized and spherical particles with a hydrophilic shell and hydrophobic core or reverse depending on their applications. Polymeric micelles could be synthesized by different methods, such as direct dissolution, dialysis method, and lyophilization. Microfluidics is also a relatively modern approach for this purpose, in which chemical reactions are carried out in the microchannels. Compared with conventional preparation methods, the microfluidic technique produces homogeneous polymeric micelles with desirable features, tunable particle size, and relatively high drug loading. These advantages are originated from the ability of microfluidics in precise control over the streamlines of reactants without chaotic turbulence. Although the synthesis of polymeric micelles by the microfluidic platform is advantageous, little or no review has been conducted to provide a clear image of the different PMs preparation by the microfluidic approach. Thus, in this review, the production of the PMs, utilizing microfluidic procedures to enhance their favorable characteristics is investigated. For this purpose, an electronic search is conducted on PubMed, Web of Science, Scopus, and Embase databases for retrieval of relevant papers. Seven papers are included in this systematic review. Preparation of PMs by the microfluidic approach and the effect of different parameters, such as the flow rate ratio, channel dimensions, drug concentration, and organic solvent type on PMs characteristics is obtained from the included papers.

Determination of Potential Genotoxic Impurity, 5-Amino-2-Chloropyridine, in Active Pharmaceutical Ingredient Using the HPLC-UV System.

A novel analytical method, based on high-performance liquid chromatography with a UV (HPLC-UV) detection system for the sensitive detection of a genotoxic impurity (GTI) 5-amino-2-chloropyridine (5A2Cl) in a model active pharmaceutical ingredient (API) tenoxicam (TNX), has been developed and validated. The HPLC-UV method was used for the determination of GTI 5A2Cl in API TNX. The compounds were separated using a mobile phase composed of water (pH 3 adjusted with orthophosphoric acid): MeOH, (50:50: v/v) on a C18 column (150 × 4.6 mm i.d., 2.7 µm) at a flow rate of 0.7 mL min-1. Detection was carried out in the 254 nm wavelength. Column temperature was maintained at 40°C during the analyses and 10 µL volume was injected into the HPLC-UV system. The method was validated in the range of 1-40 µg mL-1. The obtained calibration curves for the GTI compound was found linear with equation, y = 40766x - 1125,6 (R2 = 0.999). The developed analytical method toward the target compounds was accurate, and the achieved limit of detection and limit of quantification values for the target compound 5A2Cl were 0.015 and 0.048 µg mL-1, respectively. The recovery values were calculated and found to be between 98.80 and 100.03%. The developed RP-HPLC-UV analytical method in this research is accurate, precise, rapid, simple and appropriate for the sensitive analysis of target GTI 5A2Cl in model API TNX.

Are Molecularly Imprinted Polymers (MIPs) Beneficial in Detection and Determination of Mycotoxins in Cereal Samples?

The process of matrix clean-up and extraction of analytes has a significant influence on the detection and determination of the analyte, especially in trace amounts. Molecularly imprinted polymers (MIPs) are solid particles that can absorb specific molecules regarding the template molecule used in the synthesis process of each type of MIP. As a result, they can be used in more effective and more specific solid-phase extraction processes. On the other hand, mycotoxins are second metabolites of molds and fungus which are potentially cytotoxic and/or genotoxic even in trace amounts, and due to extensive consumption of cereals and the great concern of public health, several methods were developed and currently are in the process of development to detect and determine the presence and amounts of mycotoxins in cereals. This review is aimed to investigate the application and efficacy of MIPs in detecting and determination of mycotoxins in cereals.

Selective Recognition of Myoglobin in Biological Samples Using Molecularly Imprinted Polymer-Based Affinity Traps.

The current work demonstrates the design, characterization, and preparation of molecularly imprinted microspheres for the selective detection of myoglobin in serum samples. The suspension polymerization approach was applied for the preparation of myoglobin imprinted microspheres. For this purpose, N-methacryloylamino folic acid-Nd3+ (MAFol- Nd3+) was chosen as the complex functional monomer. The optimization studies were performed changing the medium pH, temperature, and myoglobin concentration. pH 7.0 was determined as the optimum value where the prepared imprinted microspheres displayed maximum binding for myoglobin. The maximum binding capacity was achieved as 623 mgg-1. In addition, the selectivity studies were conducted. The results confirmed that the imprinted microspheres showed great selectivity towards myoglobin in the existence of hemoglobin, cytochrome c, and lysozyme which were chosen as potentially competing proteins.

Recent Progress of Imprinted Nanomaterials in Analytical Chemistry.

Molecularly imprinted polymers (MIPs) are a type of tailor-made materials that have ability to selectively recognize the target compound/s. MIPs have gained significant research interest in solid-phase extraction, catalysis, and sensor applications due to their unique properties such as low cost, robustness, and high selectivity. In addition, MIPs can be prepared as composite nanomaterials using nanoparticles, multiwalled carbon nanotubes (MWCNTs), nanorods, quantum dots (QDs), graphene, and clays. This review paper aims to demonstrate and highlight the recent progress of the applications of imprinted nanocomposite materials in analytical chemistry.

Long-term stability and reusability of molecularly imprinted polymers.

Molecularly imprinted materials are man-made mimics of biological receptors. Their polymer network has recognition sites complementary to a substrate in terms of size, shape and chemical functionality. They have diverse applications in various chemical, biomedical and engineering fields such as solid phase extraction, catalysis, drug delivery, pharmaceutical purification, (bio)sensors, water treatment, membrane separations and proteomics. The stability and reusability of molecularly imprinted polymers (IPs) have crucial roles in developing applications that are reliable, economic and sustainable. In the present article the effect of crosslinkers, functional monomers and conditions for template extraction on the long-term stability and reusability of IPs was systematically investigated. Adsorption capacity, selectivity, morphology and thermal decomposition of eleven different l-phenylalanine methyl ester imprinted polymers were studied to reveal performance loss over 100 adsorption-regeneration cycles. Furthermore, crosslinker and functional monomer specific reversible and irreversible decomposition of imprinted polymers as a result of adsorbent regeneration were investigated through adsorption studies, electron microscopy, N2 adsorption and thermogravimetric analysis. A decomposition mechanism was proposed and revealed using NMR spectroscopy. Solutions to avoid or overcome the limitations of the most common crosslinkers, functional monomers and extraction techniques were proposed and experimentally validated.

Molecular Imprinting Technology in Quartz Crystal Microbalance (QCM) Sensors.

Molecularly imprinted polymers (MIPs) as artificial antibodies have received considerable scientific attention in the past years in the field of (bio)sensors since they have unique features that distinguish them from natural antibodies such as robustness, multiple binding sites, low cost, facile preparation and high stability under extreme operation conditions (higher pH and temperature values, etc.). On the other hand, the Quartz Crystal Microbalance (QCM) is an analytical tool based on the measurement of small mass changes on the sensor surface. QCM sensors are practical and convenient monitoring tools because of their specificity, sensitivity, high accuracy, stability and reproducibility. QCM devices are highly suitable for converting the recognition process achieved using MIP-based memories into a sensor signal. Therefore, the combination of a QCM and MIPs as synthetic receptors enhances the sensitivity through MIP process-based multiplexed binding sites using size, 3D-shape and chemical function having molecular memories of the prepared sensor system toward the target compound to be detected. This review aims to highlight and summarize the recent progress and studies in the field of (bio)sensor systems based on QCMs combined with molecular imprinting technology.

Design and Preparation of Nano-Lignin Peroxidase (NanoLiP) by Protein Block Copolymerization Approach.

This study describes the preparation of nanoprotein particles having lignin peroxidase (LiP) using a photosensitive microemulsion polymerization technique. The protein-based nano block polymer was synthesized by cross-linking of ligninase enzyme with ruthenium-based aminoacid monomers. This type polymerization process brought stability in different reaction conditions, reusability and functionality to the protein-based nano block polymer system when compared the traditional methods. After characterization of the prepared LiP copolymer nanoparticles, enzymatic activity studies of the nanoenzymes were carried out using tetramethylbenzidine (TMB) as the substrate. The parameters such as pH, temperature and initial enzyme concentration that affect the activity, were investigated by using prepared nanoLip particles and compared to free LiP. The reusability of the nano-LiP particles was also investigated and the obtained results showed that the nano-LiP particles exhibited admirable potential as a reusable catalyst.

Utilizing the Cross-Reactivity of MIPs.

The crossreactivity of molecularly imprinted polymers (MIPs) and its practical implications are discussed. Screening of MIP libraries is presented as a fasttrack route to discovery of resins selective towards new targets, exploiting the fact that MIPs imprinted with one type of template molecule also show recognition to related and sometimes also to apparently unrelated molecules. Several examples from our own and others' studies are presented that illustrate this crossreactivity and the pattern of recognition is discussed for selected examples.

Fast identification of selective resins for removal of genotoxic aminopyridine impurities via screening of molecularly imprinted polymer libraries.

This study describes the identification and evaluation of molecularly imprinted polymers (MIPs) for the selective removal of potentially genotoxic aminopyridine impurities from pharmaceuticals. Screening experiments were performed using existing MIP resin libraries to identify resins selective towards those impurities in the presence of model pharmaceutical compounds. A hit resin with a considerable imprinting effect was found in the screening and upon further investigation, the resin was found to show a broad selectivity towards five different aminopyridines in the presence of the two model active pharmaceutical ingredients (APIs) piroxicam and tenoxicam.

New synthesis method for 4-MAPBA monomer and using for the recognition of IgM and mannose with MIP-based QCM sensors.

Quartz crystal microbalance (QCM) sensors coated with molecularly imprinted polymers (MIP) have been developed for the recognition of immunoglobulin M (IgM) and mannose. In this method, methacryloylamidophenylboronic acid (MAPBA) was used as a monomer and mannose was used as a template. For this purpose, initially, QCM electrodes were modified with 2-propene-1-thiol to form mannose-binding regions on the QCM sensor surface. In the second step, the methacryloylamidophenylboronic acid-mannose [MAPBA-mannose], pre-organized monomer system, was prepared using the MAPBA monomer. Then, a molecularly imprinted film was coated on to the QCM electrode surface under UV light using ethylene glycol dimethacrylate (EDMA), and azobisisobutyronitrile (AIBN) as a cross-linking agent and an initiator, respectively. The mannose can be simultaneously bound to MAPBA and fitted into the shape-selective cavities. The binding affinity of the mannose-imprinted sensors was investigated using the Langmuir isotherm. The mannose-imprinted QCM electrodes have shown homogeneous binding sites for mannose (K(a): 3.3 × 10(4) M(-1)) and heterogeneous binding sites for IgM (K(a1): 1.0 × 10(4) M(-1); K(a2): 3.3 × 10(3) M(-1)).

4-Aminophenyl boronic acid modified gold platforms for influenza diagnosis.

As a potential pandemic threat to human health, there has been an urgent need for rapid, sensitive, simpler and less expensive detection method for the highly pathogenic influenza A virus. For this purpose, Quartz Crystal Microbalance (QCM) and Surface Plasmon Resonance (SPR) sensors have been developed for the recognition of hemagglutinin (HA) which is a major protein of influenza A virus. 4-Aminophenyl boronic acid (4-APBA) has been synthesized and used as a new ligand for binding of sialic acid (SA) via boronic acid-sugar interaction. SA has an important role in binding of HA. QCM and SPR sensor surfaces have been modified with thiol groups and then 4-APBA and SA have been immobilized on sensor surfaces, respectively. Sensor surfaces have been screened with AFM and used for the determination of HA from aqueous solution. The selective recognition of the QCM and SPR sensors toward Concanavalin A has been reported in this work. Also, the binding capacity and detection limits of QCM and SPR sensors have been calculated and detection limits were found to be 4.7 × 10(-2) µM, (0.26 µg ml(-1)) and 1.28 × 10(-1) µM, (0.72 µg ml(-1)) in the 95% confidence interval, respectively.

Synthesis and characterization of pseudo-affinity ligand for penicillin acylase purification.

The aim of this work was to test a chromatographic affinity support containing methacryloyl antipyrine (MAAP) for penicillin acylase (PA) purification by using pure penicillin acylase and crude extract. First, MAAP as a pseudo-specific ligand was synthesized by using methacryloyl chloride and 4-aminoantipyrine. Polymer beads (average size diameter: 40-120 micro m) were prepared by suspension polymerization of ethylene glycol dimethacrylate (EGDMA) and MAAP. This approach for the preparation of adsorbent has several advantages over conventional preparation protocols. An expensive and time consuming step in the preparation of adsorbent is immobilization of a ligand to the adsorption matrix. In this procedure, affinity ligand MAAP acts as comonomer without further modification steps. Poly(EGDMA-MAAP) beads were characterized by FTIR, NMR and screen analysis. Elemental analysis of MAAP for nitrogen was estimated as 89.3 micro mol/g. The prepared adsorbent was then used for the capture of penicillin acylase in batch system. The maximum penicillin acylase adsorption capacity of the poly(EGDMA-MAAP) beads was found to be 82.2 mg/g at pH 5.0. Chromatography with crude feedstock resulted in 23.2-fold purification and 93% recovery with 1.0 M NaOH.