Fabrication of magnetic polymers based on deep eutectic solvent for separation of bovine hemoglobin via molecular imprinting technology

Sensors Based on Molecularly Imprinted Polymers in the Field of Cancer Biomarker Detection: A Review

Biomarkers play a pivotal role in the screening, diagnosis, prevention, and post-treatment follow-up of various malignant tumors. In certain instances, identifying these markers necessitates prior treatment due to the complex nature of the tumor microenvironment. Consequently, advancing techniques that exhibit selectivity, specificity, and enable streamlined analysis hold significant importance. Molecularly imprinted polymers (MIPs) are considered synthetic antibodies because they possess the property of molecular recognition with high selectivity and sensitivity. In recent years, there has been a notable surge in the investigation of these materials, primarily driven by their remarkable adaptability in terms of tailoring them for specific target molecules and integrating them into diverse analytical technologies. This review presents a comprehensive analysis of molecular imprinting techniques, highlighting their application in developing sensors and analytical methods for cancer detection, diagnosis, and monitoring. Therefore, MIPs offer great potential in oncology and show promise for improving the accuracy of cancer screening and diagnosis procedures.

Ovotransferrin, an alternative and potential protein for diverse food and nutritional applications

Ovotransferrin(OVT)is a protein found in many types of egg white and has a wide range of functional properties. It has 50% homology with human/bovine lactoferrin, and is expected to be one of the most important alternative proteins for use in food and nutritional applications. This paper mainly reviews the structural characteristics and chemical properties of OVT, as well as its extraction and purification methods. It also systematically describes the various biological activities of OVT and its applications in food and medical industries. The challenges and limitations in the research of OVT were suggested. This review recommends some possible methods such as nanoparticle carriers and microencapsulation to improve the bioavailability and stability of OVT. In addition, this review highlights several strategies to overcome the limitations of OVT in terms of preparation and purification. This review systematically summarizes the recent advances in OVT and will provide guidance for the its development for food and nutritional applications.

Magnetic molecularly imprinted polymers using ternary deep eutectic solvent as novel functional monomer for hydroxytyrosol separation

In this work, magnetic molecularly imprinted polymers (MIPs) for specific recognition of Hydroxytyrosol (HT) were designed by vinyl-modified magnetic particles (Fe3O4@SiO2@VTEOs) as carrier, ternary deep eutectic solvent (DES) as functional monomer, while ethylene glycol dimethacrylate (EGDMA) as crosslinker. The optimum amount of DES was obtained by adsorption experiments (molar ratio, caffeic acid: choline chloride: formic acid = 1:6:3) which were 140 μL in total. Under the optimized amount of DES, the maximum adsorption capacity of the MIPs particles was 42.43 mg g-1, which was superior to non-imprinted polymer (4.64 mg g-1) and the imprinting factor (IF) is 9.10. Syringin and Oleuropicrin were used as two reference molecules to test the selectivity of the DES-MIPs particles. The adsorption capacity of HT was 40.11 mg g-1. Three repeated experiments show that the polymer has high stability and repeatability (RSD = 5.50).

Recent Advances in Molecular Imprinting for Proteins on Magnetic Microspheres

The separation of proteins in biological samples plays an essential role in the development of disease detection, drug discovery, and biological analysis. Protein imprinted polymers (PIPs) serve as a tool to capture target proteins specifically and selectively from complex media for separation purposes. Whereas conventional molecularly imprinted polymer is time-consuming in terms of incubation studies and solvent removal, magnetic particles are introduced using their magnetic properties for sedimentation and separation, resulting in saving extraction and centrifugation steps. Magnetic protein imprinted polymers (MPIPs), which combine molecularly imprinting materials with magnetic properties, have emerged as a new area of research hotspot. This review provides an overview of MPIPs for proteins, including synthesis, preparation strategies, and applications. Moreover, it also looks forward to the future directions for research in this emerging field.

Molecularly Imprinted Polymers with Shape-Memorable Imprint Cavities for Efficient Separation of Hemoglobin from Blood

Efficient separation and purification of hemoglobin from blood and other complicated biological fluids still remains a big challenge. Molecularly imprinted polymers (MIPs) of hemoglobin are potential choices; however, they suffer from severe problems including difficult template removal and low imprinting efficiency like other protein-imprinted polymers. Herein, a novel MIP of bovine hemoglobin (BHb) was designed in which a peptide crosslinker (PC), instead of the commonly used crosslinkers, was used. The PC, a random copolymer of lysine and alanine, adopts an α-helical conformation at pH 10 but transits to a random coil conformation at pH 5. The introduction of alanine residues lowers the pH range at which the PC undergoes helix-coil transition. The imprint cavities in the polymers are shape-memorable due to the reversible and precise helix-coil transition of the peptide segments in the polymers. They can be enlarged by lowering pH from 10 to 5, thus allowing complete removal of the template protein under mild conditions. When the pH is adjusted back to 10, their original size and shape will be recovered. Therefore, the MIP binds the template protein BHb with high affinity. Compared with the MIP crosslinked with the commonly used crosslinker, the imprinting efficiency of the PC-crosslinked MIP is significantly improved. In addition, both the maximum adsorption capacity (641.9 mg/g) and imprinting factor (7.2) are much higher than the BHb MIPs reported previously. The new BHb MIP also exhibits high selectivity toward BHb and good reusability. Thanks to the high adsorption capacity and high selectivity of the MIP, when it was applied to extract BHb from bovine blood, BHb in the blood sample was extracted almost completely, and high purity product was obtained.

Deep eutectic solvent-based manganese dioxide nanosheets composites for determination of DNA by a colorimetric method

BACKGROUND

Nucleic acid is the carrier of genetic information and the keymolecule in life science. It is important to establish a simple and feasible method for nucleic acid quantification in complex biological samples.

METHODS

Four kinds of hydrogen bond acceptors (choline chloride (ChCl), L-carnitine, tetrabutylammonium chloride (TBAC) and cetyltrimethylammonium bromide (CTAB)) were used to synthesize deep eutectic solvents (DESs) with hexafluoroisopropanol (HFIP). DESs based manganese dioxide (MnO2) nanosheets composites was synthesized and characterized. DNA concentration was determined by a UVVis spectrometer. The mechanism of DNA-DES/MnO2 colorimetric system was further discussed.

RESULTS

The composite composed of DES/MnO2 exhibited excellent oxidase-like activity and could oxidize 3,3',5,5' -tetramethylbenzidine (TMB) to produce a clear blue change with an absorbance maximum at 652 nm. When DNA is introduced, the DNA can interact with the DES by hydrogen bonding and electrostatic interactions, thereby inhibiting the color reaction of DES/MnO2 with TMB. After condition optimization, ChCl/HFIP DES in 1:3 molar ratio was used for the colorimetric method of DNA determination. The linear range of DNA was 10-130 µg/mL and exhibited good selectivity.

CONCLUSION

A colorimetric method based on DES/MnO2 was developed to quantify the DNA concentration. The proposed method can be successfully used to quantify DNA in bovine serum samples.

A boronate-affinity magnetic molecularly imprinted polymer for luteolin recognition

In this study, 3-carboxyphenylboronic acid (CP)-functionalized amino-modified Fe₃O₄ (Fe₃O₄@NH₂-CP, FNC) magnetic molecularly imprinted polymers (FNC@MIPs) were synthesized and applied for the quick identification and selective separation of luteolin (LTL). The structure and morphology were characterized in detail by Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and vibrating specimen magnetometry (VSM) methods. The FNC@MIPs had a homogeneous shape, excellent magnetic characteristics, quick binding kinetics, a high adsorption capacity, acceptable selectivity, and stable reusability. The solid-phase extraction parameters and preparation conditions were both optimized. Under optimized conditions, the maximal adsorption capacity was 14.26 mg g^-1 and the imprinting factor was 3.62. Furthermore, the experimental kinetics data were best fitted with the pseudo-first-order model (R² = 0.9877), and the Langmuir model could describe the adsorption process (R² = 0.9979), suggesting a monolayer covering. The practical application of the sorbent for LTL detection in Lonicera japonica Thunb samples showed recoveries in the range of 84.5-108.7%. Therefore, the strategy offers a fresh avenue for the extraction and purification of LTL.

Fortification of thermal and structural stability of hemoglobin using choline chloride-based deep eutectic solvents

Of late, DESs have occupied the centre stage due to their eco-friendly and resource-efficient nature and their low toxicity. In this work, we have investigated the structural and thermal stability of hemoglobin (Hb) in two choline chloride ([Ch]Cl)-based DESs namely urea [Ch]Cl-urea (DES1) and [Ch]Cl-glycerol (Gly); (DES 2). Different biophysical techniques reveal that the presence of DESs facilitates the stability of Hb in a concentration-dependent manner and the extent of stability is more pronounced in [Ch]Cl-Gly as compared to [Ch]Cl-urea. Additionally, for a better understanding of the role of DESs in modulating the thermal and structural stability of Hb, studies have been performed on Hb in the presence of individual constituents of DESs, i.e., [Ch]Cl, urea, and Gly. Altogether, it was observed that the effect on the stability of Hb was by the presence of the DESs rather than their individual constituents. For instance, urea itself is a destabilizing co-solvent for biomolecules. However, the harmful effects of urea were surpassed when a DES is formed in the presence of [Ch]Cl. Therefore, overall, it can be concluded that both DESs can be described as potential non-harmful, green, and promising solvents for enhancing the structural and thermal stability of Hb.

Development of Magnetic Deep Eutectic Solvent-Based Liquid-Liquid Extraction for the Selective Extraction and Separation of RNA

Four kinds of hydrophobic magnetic deep eutectic solvents (HMDESs) were prepared and applied to RNA extraction. Based on the HMDESs, a mechanical shaking-assisted liquid-liquid extraction (MSLLE) was developed for the extraction of RNA. Factors that influence the extraction, including the extraction time, temperature, volume of HMDES, buffer types, and pH, were evaluated. After the optimization of all conditions, the RNA extraction efficiency was 82.31 ± 0.02%. RNA can be extracted from complex samples and medicinal yeast by the method proposed in this work and can be recovered from the HMDESs after being extracted.

Current understanding and insights towards protein stabilization and activation in deep eutectic solvents as sustainable solvent media

Deep eutectic solvents (DESs) have emerged as a new class of green, designer and biocompatible solvents, an alternative to conventional organic solvents and ionic liquids (ILs) which are comparatively toxic and non-biodegradable. DESs are eutectic mixtures that are formed when a hydrogen bond acceptor (HBA) is mixed with a hydrogen bond donor (HBD) at particular molar ratios by mechanical grinding or under mild heating conditions. Very recently, these solvents have been the center of attention for researchers in biotechnology, biomedicine and various scientific applications. These environmentally benign solvents have a close analogy with ILs; however, they offer certain unique merits over traditional ILs. DESs display remarkable properties such as easy preparation, tunable composition, biodegradability, recyclability, inherently low toxicity, sustainability and biocompatibility; these special features validate DESs as new potential solvents/co-solvents for biomolecules. Mechanistically, the biocompatibility and protein friendly nature of DESs depend on various factors, which include the composition of the DES, viscosity and hydration level. Therefore, it becomes an essential task to bring together all the studies related to protein behaviour in DESs to unlock their biomolecular proficiency. This review specifically highlights recent insights into the biomacromolecular functionality in DESs, including outlines of the solubilization and stabilization of proteins, long term protein packaging, different extraction methods and enzyme activation in the presence of DESs. A literature survey reveals that DESs act as green media in which the protein structure and activity are retained. In some cases, proteins refolded and enzymatic activity was enhanced several fold in the presence of DESs. Furthermore, we have reviewed the possible mechanistic behaviour behind protein stabilization, refolding and activation in DESs. Overall, the main objective of this review is to explicate the advantages of the introduction of DESs for biomolecules and to demonstrate the versatility of these eco-friendly solvents for future bio-based applications.

Deep eutectic solvent-modified mixed iron hydroxide-silica: Application in magnetic solid-phase extraction for enrichment of organochlorine pesticides prior to GC-MS analysis

A new type of magnetic material based on silica-coated mixed iron hydroxides functionalized with deep eutectic solvent was utilized for the magnetic solid-phase extraction of organochlorine pesticides prior to gas chromatography-mass spectrometry analysis. Choline chloride and phenol were selected as the hydrogen bond acceptor and donor, respectively, for preparing the deep eutectic solvent-modified magnetic surface. The modified surface possessed superior enrichment capability for organochlorine pesticides. Under optimal extraction conditions, viz., 10 mg sorbent, 5 mL sample solution, and 200 μL acetone (desorption solvent), linearity was obtained in the range 0.005-200 μg/L, with coefficients of determination greater than 0.997. The limits of detection and quantification were as low as 0.6-10 and 5-60 ng/L, respectively, whereas the enrichment factors were in the range of 31-100. The precisions evaluated in terms of the relative standard deviations of the intra- and inter-day experiments were <4.9 and 7.6%, respectively. The developed method was successfully applied for determining the organochlorine residues in agricultural products. Satisfactory recoveries in the range of 71.2-110.3% were obtained, with a relative standard deviation of <8.0%. The proposed material is a promising sorbent for the preconcentration of organochlorine residues.

A molecularly imprinted polymer based on MOF and deep eutectic solvent for selective recognition and adsorption of bovine hemoglobin

In this study, a novel kind of imprinted polymers based on metal-organic frameworks (MOF@DES-MIPs) was prepared, using bovine hemoglobin (BHb) as template molecules and deep eutectic solvents (DES) as functional monomers for selective recognition and adsorption of BHb. MOF were used as the substrates to improve the accessibility of imprinted sites and DES as the functional monomers to produce different forces for BHb to help the formation of imprinted sites. Imprinted polymer films were taken to provide analyte selectivity. The MOF@DES-MIPs prepared were characterized and evaluated by scanning electron microscope, X-ray diffraction, and Fourier transform infrared spectrometer. We also investigated the influences of BHb concentration and adsorption time on the performance of MOF@DES-MIPs. The maximal adsorption capacity of MOF@DES-MIPs to BHb reached 151.28 mg g^-1, and the MOF@DES-MIPs showed good selectivity and fast adsorption equilibrium, which might offer a novel method for the preparation and research of molecularly imprinted polymers of biomacromolecules. In addition, MOF@DES-MIPs were successfully applied in the selective recognition of BHb from a real bovine blood sample. Graphical abstract.

Molecularly Imprinted Polymers for Dispersive (Micro)Solid Phase Extraction: A Review

The review describes the development of batch solid phase extraction procedures based on dispersive (micro)solid phase extraction with molecularly imprinted polymers (MIPs) and magnetic MIPs (MMIPs). Advantages and disadvantages of the various MIPs for dispersive solid phase extraction and dispersive (micro)solid phase extraction are discussed. In addition, an effort has also been made to condense the information regarding MMIPs since there are a great variety of supports (magnetite and magnetite composites with carbon nanotubes, graphene oxide, or organic metal framework) and magnetite surface functionalization mechanisms for enhancing MIP synthesis, including reversible addition-fragmentation chain-transfer (RAFT) polymerization. Finally, drawbacks and future prospects for improving molecularly imprinted (micro)solid phase extraction (MIMSPE) are also appraised.

Specific recognition of protein by deep eutectic solvent-based magnetic β-cyclodextrin molecularly imprinted polymer

A magnetic β-cyclodextrin (MCD) surface molecularly imprinted polymer (MIP) based on deep eutectic solvents (DESs) as cross-linker and functional monomer (MCD@DES-MIP) was successfully synthesized for the specific recognition of bovine hemoglobin (BHb). The adsorption behavior of MCD@DES-MIP for BHb was investigated by adsorption thermodynamics, adsorption kinetics, and pH control experiments. The maximum adsorption capacity of MCD@DES-MIP for BHb under the optimized conditions was 195.94 mg g^-1 and the imprinting factor was 4.68. In addition, the competitive adsorption experiments demonstrated that MCD@DES-MIP showed excellent selective extraction ability for BHb in the binary mixture of BHb and bovine serum albumin (BSA). The actual sample analysis manifested that MCD@DES-MIP effectively separated BHb from complex samples. The results of circular dichroism spectra proved that the secondary structure of BHb did not change during elution. The result indicated that MCD@DES-MIP can be used as a new imprinting material for the separation and purification of BHb.Graphical abstract Magnetic imprinted microspheres (MCD@DES-MIP) were prepared by free radical polymerization using magnetic β-cyclodextrin (MCD) as carrier, deep eutectic solvents (DESs) as functional monomer and cross-linker. MCD@DES-MIP show high adsorption capacity and excellent selectivity for BHb.

Fabrication of metal coordination-synergistic magnetic imprinted microspheres based on ligand-free Fe3O4-Cu for specific recognition of bovine hemoglobin

In this work, a synergistic imprinting strategy combined with metal coordination based on ligand-free Fe₃O₄-Cu was proposed to fabricate molecularly imprinted polymers (MIPs) for the recognition and isolation of bovine hemoglobin (BHb) specifically in biological samples. Copper doped magnetic microspheres prepared solvothermally in a one-pot pathway act as both magnetic core and metal affinity substrate. Upon anchoring BHb to Fe₃O₄-Cu through metal coordination, the imprinted layer was formed via dopamine self-polymerization. Profiting from the synergistic effect, the obtained imprinted microspheres exhibited an enhanced adsorption performance with the adsorption capacity of 400.86 mg g^-1, imprinting factor of 11.88, selectivity coefficient above 5.8, superior to most of other reported BHb-MIPs. Furthermore, kinetic adsorption analyses pointed to a chemisorption-limited process as described by the pseudo-second-order model, and the isothermal adsorption analyses implied monolayer adsorption, as described by the Langmuir model. In addition, the resultant magnetic MIPs can be used at least six adsorption-desorption cycles without re-incubation in the metallic salt solution, avoiding secondary environmental pollution. Furthermore, the well-defined materials showed selectivity both in individual protein samples and bovine serum, providing a promising potential in bioseparation.

Sustainable green solvents for microextraction techniques: Recent developments and applications

The development and application of alternative green solvents in analytical techniques consist of trends in sample preparation, since this subject represents an important step toward sustainability in experimental procedures. This review is focused on the main theoretical aspects related to deep eutectic solvents (DES), switchable hydrophilicity solvents (SHS) and supramolecular solvents (SUPRAS). Recent applications are highlighted, particularly for the extraction of different analytes from environmental, biological and food matrices. Moreover, novel configurations are emphasized, aiming for efficient, automated and high-throughput procedures. This review also provides some critical points regarding the use of these solvents and their green aspects.

The study and application of biomolecules in deep eutectic solvents

Deep eutectic solvents offer stimulating possibilities for biomolecular stabilization and manipulation, biocatalysis, bioextraction, biomass processing, and drug delivery and therapy.

Poly-l-lysine-functionalized magnetic graphene for the immobilized metal affinity purification of histidine-rich proteins

Metal affinity-poly-l-lysine functionalization on a magnetic graphene substrate for simultaneously improving the adsorption selectivity toward histidine-rich proteins and inhibiting the non-specific adsorption.

Specific adsorption and determination of aspartame in soft drinks with a zein magnetic molecularly imprinted modified MGCE sensor

Schematic representation of the synthesis procedure of ZDM-MIPs.

Selective separation and inexpensive purification of paclitaxel based on molecularly imprinted polymers modified with ternary deep eutectic solvents

Paclitaxel (PTX) is a powerful anticancer natural product, with its separation and purification having been widely studied. In this work, new molecular imprinted polymers (MIPs) using deep eutectic solvents (DESs) with different molar ratios were prepared as functional monomers. These were then used as adsorbents in solid phase extraction (SPE) for the separation of PTX from its structural analogs. The polymers were characterized by energy disperive X-rays (EDX), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FT-IR). The results suggested that the formative regular DES-MIPs had an even pore-size distribution and a large specific surface area. The dynamic adsorption and static adsorption showed that the DES-MIPs had excellent adsorption performance, with a maximum adsorption capacity and optimum adsorption time of 87.08 mg/g and 180 min, respectively. The selective adsorption experiments showed that the material had outstanding selectivity, and the maximum selectivity factor was 6.20. For stability, after six consecutive adsorption and desorption cycles, the DES-MIPs maintained the perfect stability and reusability. Furthermore, the fabricated SPE column was successfully utilized for extracting and eluting PTX. This study provides a reliable protocol for the separation and purification PTX from its structural analogs and the DES-MIPs materials have excellent potential application value in pharmaceutical industry.

Simultaneous extraction of several targets by using non-toxic dual template molecularly imprinted polymers in vivo and in vitro

In this report, a non-toxic Dual Template Molecularly Imprinted Polymers (DMIPs) was synthesized with quercetin and schisandrin b as template molecules, using deep-eutectic solvents as functional monomers for the first time. The DMIPs were used to efficiently and simultaneously enrich quercetin and schisandrin b from the mixed crude extracts of penthorum and schisandra. The results indicated that the DMIPs exhibited rapid adsorption kinetics (80 min for adsorption equilibrium) and high selectivity. The largest adsorbing capacities to quercetin and schisandrin b were 23.58 mg/g and 41.64 mg/g, respectively. After presaturation with quercetin and schisandrin b, the nontoxic saturated DMIPs were fed to the mice. Blood samples of the mice were taken and both quercetin and schisandrin b were successfully detected. The pharmacokinetics of quercetin and schisandrin b were similar to reports in the literature where mice were directly fed with botanicals. Our study provides a reliable protocol such that DMIPs can be used to separate and enrich several target molecules simultaneously from complex biological systems. Our findings suggested that the DMIPs have potential application as a drug delivery system of compound herbal formulas.

A composite consisting of a deep eutectic solvent and dispersed magnetic metal-organic framework (type UiO-66-NH2) for solid-phase extraction of RNA

A cactus-shaped magnetic composite was prepared for solid-phase extraction of RNA. It is composed of the metal organic framework UiO-66-NH₂ that was modified with Fe₃O₄ nanoparticles. The composite was then dispersed in a lactic acid-based deep eutectic solvent (DES, Fe₃O₄-COOH@UiO-66-NH₂@DES). The structures of the sorbents were characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectrometry, vibrating sample magnetometry and thermogravimetric analysis. The extraction performance of sorbents was optimized and the maximum extraction capacity reached 246 mg·g^-1. Extraction is shown to mainly rely on chelation interaction, electrostatic interaction, hydrophobic interaction and hydrogen bonding interaction. The sorbent can selectively extract RNA over DNA, bovine hemoglobin and amino acids. Regeneration studies indicated that the sorbent can be re-used (after regenreation with DES) several times without obvious change of the extraction capacity. The successful extraction of RNA from yeast testified the practical application of the sorbent. Graphical abstractSchematic representation of the fabrication Fe₃O₄-COOH@UiO-66-NH₂@DES, and its application in the magnetic solid phase extraction of RNA.

A composite prepared from MnO2 nanosheets and a deep eutectic solvent as an oxidase mimic for the colorimetric determination of DNA

A composite was fabricated from deep eutectic solvent and MnO₂ nanosheets (DES/MnO₂) and is shown to be a viable oxidase mimic. The property, morphology and composition of DES/MnO₂ was characterized. DES/MnO₂ displays oxidase-like activity and can oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to form a blue product (oxTMB) with an absorption maximum at 652 nm. Due to the presence of the DES, the polyanionic and negatively charged DNA is easily adsorbed on the surface of the composite by hydrogen bonding and electrostatic interactions. This leads to the inhibition of the oxidase-mimicking activity of DES/MnO₂. This finding was used to design a colorimetric method for the determination of DNA. The assay work in the 10-100 μg mL^-1 DNA concentration range and has a detection limit of 0.37 μg mL^-1. The inhibiting mechanism was further studied by zeta potential measurements, dynamic light scattering and transmission electron microscopy. The selectivity study shows the DES/MnO₂-TMB system to be highly selective for DNA when compared with many proteins, carbohydrates, salts and amino acid. RNA, on the other hand, interferes. The real sample analysis result illustrates that the new method can be used for the detection of DNA in bovine whole blood. Graphical abstractA novel oxidase mimic based on deep eutectic solvent-functionalized MnO₂ nanosheets was synthesized, which can directly catalyze oxidation of 3,3',5,5'-tetramethylbenzidine (TMB, colorless) to oxTMB (blue). A sensitive and convenient colorimetric strategy for visual detection of DNA was established through DES/MnO₂-TMB sensing system.

pH-responsive polymer assisted aptamer functionalized magnetic nanoparticles for specific recognition and adsorption of proteins

A new adsorbent based on pH-responsive polymer assisted aptamer functionalized magnetic nanoparticles was developed for specific recognition and efficient adsorption of proteins. Arising from the synergistic effect of specific affinity of apatamer on protein and tunable hydrophobic/hydrophilic property of pH-responsive polymer, the adsorbent exhibited excellent adsorption capacity for target protein. Notably, because of the pH-responsive property of the polymer, the adsorption and desorption process could be regulated through varying environmental pH. The resultant adsorbent that immobilized with lysozyme binding aptamer was successfully applied in specific recognition and efficient adsorption of lysozyme in egg white samples and good recovery results in the range of 95.2-103.2% were obtained. Moreover, the adsorbent immobilized with cytochrome C binding aptamer also exhibited satisfactory adsorption to cytochrome C. The synergistic effect of pH-responsive polymer and aptamer promoted the recognition selectivity and adsorption capacity to target protein, illustrating a facile way for construction of more specific protein adsorbents.

Polymer Science and Engineering Using Deep Eutectic Solvents

The green and versatile character of deep eutectic solvents (DES) has turned them into significant tools in the development of green and sustainable technologies. For this purpose, their use in polymeric applications has been growing and expanding to new areas of development. The present review aims to summarize the progress in the field of DES applied to polymer science and engineering. It comprises fundamentals studies involving DES and polymers, recent applications of DES in polymer synthesis, extraction and modification, and the early developments on the formulation of DES–polymer products. The combination of DES and polymers is highly promising in the development of new and ‘greener’ materials. Still, there is plenty of room for future research in this field.

The construction of porous chitosan microspheres with high specific surface area by using agarose as the pore-forming agent and further functionalized application in bioseparation

Adsorbents with synchronously high protein adsorption performance and a facile synthetic route are highly desired in protein separation.