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Several factors should be considered in the administration of therapeutics, including the adaptability of drug release rates, the preservation of fragile drugs, and ensuring patient comfort and compliance. By integrating clinical and engineering principles, drug delivery systems (DDSs) present a great opportunity for the design of a clinically viable formulation in the diagnosis, treatment, and prevention of diseases. DDSs have a significant potential to enable controlled release of therapeutic agents at the target site, for example, cells, tissues, and organs. Controlled and targeted DDSs aim to reduce the required dose and risk of systemic side effects while increasing therapeutic efficacy. A wide variety of DDSs has been developed to date and is still being developed. Some of these are hydrogels, nanogels, dendrimers, liposomes, microspheres, magnetic nanoparticles, quantum dots, nanosponges, and micelles. DDSs can be used in various clinical improvements, such as lessening the risk of drug-resistant bacterial infections or increasing the efficacy of diabetes treatment. Due to their advantages, DDSs have been in development in cancer treatment, stem cell therapy, inflammatory diseases, and gene delivery. This chapter will discuss current trends and future trials of clinical applications of DDSs as well as their in vitro and in vivo performance, and preclinical assessment. © 2023 Elsevier Inc. All rights reserved.

Conductive cryogels have gained significant research interest in recent years due to their potential biomedical applications such as implantable and wearable devices, biosensors, medical patches, health recording electrodes, drug delivery systems, bioactuators, etc. In this study, poly(2-hydroxyethy methacrylate)/polypyrrole (PHEMA/PPy) cryogel possessing macroporous morphology, conductivity, cytocompatibility, and mechanical compression properties were produced by cryopolymerization in the presence of excess ammonium persulfate. Electrical properties of the PHEMA and PHEMA/PPy cryogels as a function of frequency were compared using electrical impedance spectroscopy. At low frequencies, the real part of the dielectric constant of the PHEMA was found to be about 4-fold higher than that of the PHEMA/PPy whereas the average imaginary dielectric constant of PHEMA/PPy cryogels was observed to be nearly 6-fold higher than that of the PHEMA cryogels at the same frequency region. This behavior suggests that the addition of polypyrrole to the PHEMA cryogel increases the conductivity of the resultant material. This claim is further supported by comparing the results of the loss tangent, impedance and AC conductivity variations as a function of frequency for all samples. According to cytotoxicity, morphological, and AO/EB staining studies. PHEMA/PPy cryogel did not cause any toxic effect on L929 cells, except for PHEMA/PPy4 extract. These data suggested that the PHEMA/PPy cryogel with conductivity and cytocompatibility is a promising candidate in biotechnology and biomedical engineering. © 2023 Elsevier Ltd

Macroporous polymeric gels has received great attention in many fields focused on biotechnological applications. In this study, two new HEMA-based cryogel columns were synthesized. To this end, poly(HEMA-VF) and poly(HEMA-NVP) cryogels were prepared by copolymerization of 2-Hydroxyethyl methacrylate (HEMA) with N-vinylformamide (VF) and N-vinylpyrrolidone (VP) in the presence of N,N-methylenebisacrylamide (as cross-linker), then polymerization initiated by ammonium persulfate (APS) and N,N,N ',N '-tetramethylenediamine (TEMED) with free-radical polymerizations method in cryogelation conditions, respectively. p(HEMA-VF) and p(HEMA-VP) cryogels contain a continuous polymeric matrix with interconnected pores of size 2-100 mu m. Swelling behavior for these cryogels in various solvents was investigated, wherein the characterization of the cryogels is conducted via by surface area measurement (BET), Fourier transforms infrared spectroscopy (FT-IR), elemental analysis, scanning electron microscopy (SEM), Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). As drug model compounds, Methyl Red (MR), methylene blue (MB) and methylene green (MG) were loaded into prepared cryogels and the controlled release properties of cryogel columns were examined comparatively each other. It has been shown that approximately 90% of its release from the cryogels occurred within about 2 h. In addition, MB release from p(HEMA-VF) and p(HEMA-VP) cryogels was found to be around 80% over a similar period. The proposed cryogels can be regarded as controlled release system on future biomedical applications. Duzce University Research FundDuzce University [2019.05.03.1024] This work was supported financially by the Duzce University Research Fund (Grant Number 2019.05.03.1024). WOS:000614319600001 2-s2.0-85100293367

In the present study, the enantiomeric forms of hydrophobic amino acids ( l -tryptophan, l -tyrosine, and l -phenylalanine) were separated by molecularly imprinted capillary columns (MICC) via Capillary Electrochromatography (CEC) for the first time. The monomer ratio, crosslinker ratio, template molecule ratio, the porogen ratio and type, polymerization time, and also the effect of temperature were examined to increase the permeability properties of MICC. FTIR, SEM and BET analyses were realized for the characterization of MICC. The effect of the electric field, organic solvent ratio, and pressure were carried out experimentally to determine the optimum conditions. The separation performances of MICC and the non-imprinted capillary columns (NICC) were compared electrochromatographically.

Estradiol, a phenolic steroid oestrogen, is one of the endocrine-disrupting chemicals (EDCs) found in natural and tap waters. The detection and removal of EDCs is attracting attention daily as they negatively affect animals’ and humans’ endocrine functions and physiological conditions. Therefore, developing a fast and practical method for the selective removal of EDCs from waters is essential. In this study, we prepared 17β-estradiol (E2)-imprinted HEMA-based nanoparticles onto bacterial cellulose nanofibres (E2-NP/BC-NFs) to use for the removal of E2 from wastewater. FT-IR and NMR confirmed the structure of the functional monomer. The composite system was characterised by BET, SEM, µCT, contact angle, and swelling tests. Additionally, the non-imprinted bacterial cellulose nanofibres (NIP/BC-NFs) were prepared to compare the results of E2-NP/BC-NFs. Adsorption of E2 from aqueous solutions was performed in batch mode and investigated via several parameters for optimisation conditions. The effect of pH studies was examined in the 4.0–8.0 range using acetate and phosphate buffers and a concentration of E2 of 0.5 mg/mL. The maximum E2 adsorption amount was 254 µg/g phosphate buffer at 45 °C. The experimental data show that the Langmuir is a relevant isotherm model for E2 adsorption. Additionally, the relevant kinetic model was the pseudo-second-order kinetic model. It was observed that the adsorption process reached equilibrium in less than 20 min. The E2 adsorption decreased with the increase in salt at varying salt concentrations. The selectivity studies were performed using cholesterol and stigmasterol as competing steroids. The results show that E2 is 46.0 times more selective than cholesterol and 21.0 times more selective than stigmasterol. According to the results, the relative selectivity coefficients for E2/cholesterol and E2/stigmasterol were 8.38 and 86.6 times greater for E2-NP/BC-NFs than for E2-NP/BC-NFs, respectively. The synthesised composite systems were repeated ten times to assess the reusability of E2-NP/BC-NFs.

Tribology is one of the most important issues for the repair and regeneration of living tissues in the human body, as it deals with the wear, lubrication, and friction of interrelated surfaces. Hydrogels show potential as cartilage regeneration agents due to their biocompatibility and behave similarly to the lubricating mechanisms found in cartilage tissue. Cryogels, which are included in the class of hydrogels, are more stable than hydrogels in terms of mechanical strength, and references to the tribological properties of these polymers in the literature have been minimal so far. In this study, poly(HEMA-N-vinyl formamide) (poly(HEMA-NVF) and poly(HEMA-N-vinylpyrrolidone) (poly(HEMA-NVP) cryogels with improved hydrophilic properties were synthesized with pure poly(HEMA) cryogel. The swelling properties of HEMA-based cryogels were examined under the heading of various parameters, and their physicochemical characterizations were characterized via FTIR, SEM, mercury intrusion porosimetry, elemental analysis (EDX), and TGA methods. Before investigating tribological properties, a cytotoxicity test was performed for all cryogels. Then, in line with the study's primary purpose, the tribological properties of cryogels were examined. Abrasion tests were carried out on a pin-on-disc tester linked with ASTM G99-05 standard. According to the results, the friction coefficient of poly(HEMA-NVF) and poly(HEMA-NVP) cryogels is 21.62% and 10.51% higher than poly(HEMA) cryogel, respectively. In addition, the results of abrasion and 3D surface topography images prove that the poly(HEMA-NVP) cryogel wears less and its surface is less deformed than other cryogels.

Quantum dot-filled polymer nanocomposites are recent of interest due to the improvement of the properties and possibility of use in diverse application areas. In this study, poly(HEMA) cryogels and CsPbCl3 and CsPbBr3 perovskite quantum dots were separately synthesized and then perovskite quantum dots/cryogel nanocomposites were formed for the first time. After comprehensive characterizations of the nanocomposites, the dielectric properties of those structures were studied using impedance spectroscopy. All characterization methods revealed the effective formation of the quantum dot/cryogel nanocomposites. The real part of the dielectric components of the nanocomposites decreased concerning the pure cryogel. For the CsPbCl3 quantum dots filled nanocomposites, the imaginary part of the dielectric component and the loss tangent parameter increased almost by the factors of similar to 1.8 and similar to 2.2, respectively. On the other hand, for the CsPbBr3 quantum dots filled cryogel, the imaginary part of the dielectric component and the loss tangent parameter values decreased by the factors of similar to 2.6 and similar to 2 respectively. The large dielectric losses in the case of CsPbCl3 quantum dot-based nanocomposite were attributed to the high existence of surface traps on the surface of the CsPbCl3 quantum dots.

A simple and novel Schiff base chemosensor (BMHM) based on benzimidazole was synthesized. In ethanol-water (1:1, v/v) medium on varying concentrations of Zn2+ chemosensor exhibited a strong and quick turn on fluorescence response. The Zn2+ recognition was based on the Chelation-enhanced fluorescence effect. The binding constant and limit of detection for BMHM-Zn2+ complexation were estimated to be 7.99 x 104 M-1 and 0.148 mu M, respectively. The extreme fluorescent enhancement caused by Zn2+ binding in chemosensor BMHM occurred at a pH range of 6-7. The practical use of chemosensor BMHM was tested by determination of Zn2+ in real water samples and comparing the results with the data obtained using high resolution inductively coupled plasma mass spectrometry. Duzce University Scientific Research Projects UnitDuzce University [2017.05.03.620, 2019.05.03.947] This study was supported by Duzce University Scientific Research Projects Unit (Project numbers: 2017.05.03.620 and 2019.05.03.947). WOS:000695788400003 2-s2.0-85114898871 PubMed: 34519936

Recognition mechanism and enantiomerically separations of the chiral compounds are subjects that always stimulate the great interest of researchers in pharmacology and natural sciences, who are interested in finding solutions for both analytical purity and preparative purposes. Capillary Electrophoresis has become one of the most important analytical approaches for enantiomeric separations due to its superior properties, such as high resolution and high efficiency of chiral selectors. In this field, where researchers continue to be interested, the distinctions continue to develop day by day, with the introduction of new techniques developed on the basis of Capillary Electrophoresis philosophy in parallel with the development process of technology, as well as the chiral selectors of many different forms. In this review, besides some descriptive theoretical information about capillary electrophoresis and the techniques associated with it, studies on chiral separations using different chiral selectors or different chiral additives, such as molecularly imprinted polymers, cyclodextrins, Metal-organic frameworks, ionic liquids, nanoparticles and monoliths in the last nearly 10 years (2010-2020) were examined.

Sarkaya, Koray/0000-0003-0177-5134 WOS: 000487100600013 In the present study, a novel ion-imprinting and non-imprinting cryogel samples have been prepared using ion-imprinting technique and the dielectric properties have been investigated using an impedance spectroscopy method. In the preparation of ion-imprinted cryogel, at the first attempt, N-methacryloly-(l)-cysteine methyl ester was used as the metal complexing monomer. Ag+-imprinted poly(hydroxyethyl methacrylate-N-methacryloly-(l)-cysteine methyl ester) cryogel was produced by bulk polymerization. Poly(2-hydroxyethyl methacrylate) was selected as the basic matrix by considering properties, high chemical and mechanical stability. After removal of template (silver ions), the ion-imprinted cryogel was used for the removal of photo-film-containing materials. The dielectric properties of cryogel samples have also been investigated by impedance spectroscopy within the frequency range of 1 Hz-10 MHz. The real part of the permittivity increases at low frequencies as electrode effects become dominant. It shows a constant value at high frequencies due to dipole polarization. On the other hand, the imaginary part does not show a relaxation peak as the relaxation time of samples is very short. The frequency dependence of electrical modulus has also been investigated. The real part of electrical modulus (M ' (f)) is an indicative of negligible electrode polarization phenomenon in the test material. The behavior of the imaginary part of frequency dependent electrical modulus (M '' (f)) exhibit that the dielectric relaxation process is usually not frequency-activated state. Dielectric relaxation process occurs spontaneously due to the hopping mechanism of charge carriers.

Bu çalışmada ilk olarak, süper-gözenekli poli(N-izopropilakrilamit) (p(NIPAM)) kriyojeli, -16°C'dekriyojelasyon yöntemi ile sentezlenmiştir. Polimerizasyon işleminde, NIPAM monomer olarakkullanıldı ve çapraz bağlayıcı olarak N,N'-metilen-bis-akrilamid (MBAAm) tercih edildi. Reaksiyonkoşullarının sağlanabilmesi açısından diğer reaktifler olarak ise reaksiyon redoks başlatıcı çiftiN,N,N,N?-tetrametilen diamin (TEMED) ve amonyum persülfat (APS) varlığında polimerizasyongerçekleştirildi. Hazırlanan p(NIPAM) kriyojellerinin şişme ve makrogözeneklilik testlerininincelenmesinin yanı sıra, Fourier dönüşümlü kızılötesi (FTIR) spektroskopisi ve Yüzey TaramalıElektron mikroskobu ile karakterize edildi. p(NIPAM) kriyojellerinin termal kararlılıklarınınbelirlenebilmesi amacıyla Termal Gravimetrik Analiz (TGA) yöntemlerine başvuruldu. NIPAM bazlıkriyojellerin karakterizasyon ölçümlerinin belirlenmesinden sonra ise kriyojellerin dahil olduğu sınıfolan hidrojellere ait bu kez NIPAM-bazlı hidrojel sentezlenerek aynı koşullar üzerindenkarakterizasyon sonuçları karşılaştırıldı. In this study, firstly, the super-porous poly (N-isopropylacrylamide) (p(NIPA)) cryogel was synthesized by cryogelling method at -16°C. In the polymerization process, NIPA was used as the monomer and N, N'-methylenebisacrylamide (MBAAm) was preferred as the crosslinker. As other reagents, polymerization was carried out in the presence of reaction redox initiator pair N,N,N,N?- tetramethylene diamine (TEMED) and ammonium persulfate (APS) to ensure the reaction conditions. The p(NIPAM) cryogels were characterized by swelling and macroporosity tests, as well as Fourier transform infrared (FTIR) spectroscopy and Surface Scanning Electron Microscopy. Differential Scanning Calorimetry (DSC) and Thermal Gravimetric Analysis (TGA) methods were used to determine the thermal stability of p(NIPAM) cryogels. After determining the characterization measurements of NIPA based cryogels, this time NIPAM-based hydrogel, which belongs to the class of hydrogels including cryogels, was synthesized and the results were compared over the same conditions.

Cryogels are an outstanding class of materials with special and functionalized physical properties in various fields and privileges for different industrial applications. Due to unique properties of quantum dots, properties of cryogels can be engineered by adding quantum dots in. In this study, both p(HEMA)-based cryogel and CdSe QDs synthesized and characterized, separately. Then, CdSe QDs were loaded into p(HEMA) cryogels by immersing cryogel into QDs solutions. FTIR-ATR, SEM and TGA characterizations were performed to ensure that CdSe QDs penetrate p(HEMA) cryogels effectively. Dielectric properties of CdSe QDs-loaded cryogel were investigated using Electrical Impedance Spectroscopy (EIS). Real and imaginary parts of dielectric constants were decreased significantly at low frequencies in QD-loaded cryogels. While real part of impedance was increased in CdSe QDs-loaded cryogel at low frequencies. In addition, at high frequencies, those parameters were observed to be same in both cases. Duzce University Scientific Research Project (DUBAP)Duzce University [2017.06.03.592] Authors kindly would like to thank Duzce University Scientific Research Project (DUBAP) Coordination for the support with the project number of 2017.06.03.592. WOS:000562679400007 2-s2.0-85087508329

A dopamine-imprinted monolithic column was prepared and used in capillary electrochromatography as stationary phase for the first time. Dopamine was selectively separated from aqueous solution containing the competitor molecule norepinephrine, which is similar in size and shape to the template molecule. Morphology of the dopamine-imprinted column was observed by scanning electron microscopy. The influence of the organic solvent content of mobile phase, applied pressure and pH of the mobile phase on the recognition of dopamine by the imprinted monolithic column has been evaluated, and the imprinting effect in the dopamine-imprinted monolithic polymer was verified. Developed dopamine-imprinted monolithic column resulted in excellent separation of dopamine from structurally related competitor molecule, norepinephrine. Separation was achieved in a short period of 10 min, with the electrophoretic mobility of 5.81x10(-5)m(2)V(-1)s(-1) at pH 5.0 and 500mbar pressure.