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Development of AS1411aptamer-conjugated liposomes for targeted delivery of arsenic trioxide is the primary goal of this study. AS1411aptamer was used as ligand to target nucleolin, which is highly expressed on the surface of melanoma cancer cells. The targeted liposomes were constructed by the thin film method, and arsenic trioxide was loaded as cobalt (II) hydrogen arsenite (CHA) to increase the loading efficiency and stability of the liposomes. The liposomal structure was characterized by Fourier Transform Infrared Spectroscopy (FT-IR) and field emission scanning electron microscopy (FESEM). In addition, particle sizes and zeta potential of the CHA-loaded liposomes (CHAL) and aptamer-functionalized CHA-loaded liposomes (AP-CHAL) were determined. In vitro cytotoxicity of CHAL and AP-CHAL were evaluated using MTT assay in murine melanoma (B16) and mouse embryonic fibroblast (MEF) cell lines. The encapsulation efficiency of CHAL and AP-CHAL was reported as 60.2 ± 6.5% and 58.7 ± 4.2%, respectively. In vivo antitumor activity of CHAL and AP-CHAL in the B16 tumor-xenograft mouse model was dramatically observed. All mice of both groups survived until the end of treatment and showed body weight gain. The tumor protrusion completely disappeared in 50% of the mice in these groups. Furthermore, histopathology studies demonstrated that CHAL and AP-CHAL did not induce significant toxicity in healthy mice tissues. However, unlike the CHAL group, which showed an initial increase in tumor volume, a specific antitumor effect was observed in the AP-CHAL group from the beginning of treatment. The results showed that AP-CHAL can be used as an effective drug delivery system with high potential in the treatment of solid tumors. [ABSTRACT FROM AUTHOR]

Standard purification systems have mainly demonstrated the inefficient removal of neonicotinoid insecticides with high persistence in the environment. In the present work, a new magnetic adsorbent composed of Fe3O4 and CuO nanoparticles impregnated with activated carbon (AC) has been used to remove imidacloprid (IMCP) as the most common neonicotinoid insecticide from the water solutions. Various techniques such as Fourier Transform infrared spectroscopy, x-ray diffraction, field emission scanning electron microscopy, energy-dispersive x-ray diffraction, and vibrating sample magnetometer were employed to characterise the fabricated composite. The main affecting parameters, including adsorbent amount, solution pH, agitating time, initial pesticide concentration, and temperature, were examined to obtain the optimised conditions. According to the obtained results from kinetic and isotherm modelling, the adsorption mechanism of IMCP on Fe3O4/CuO@AC nanocomposite (NC) is a combination of chemisorption and physisorption phenomena. The presence of heterogeneous sites for IMCP adsorption was shown by fitting the experimental data to the Freundlich isotherm model. In addition, the adsorption process was well consistent with the pseudo-second-order kinetic model, which indicates that chemisorption is the determining step in the adsorption process. Thermodynamic data showed the exothermic and spontaneous nature of the adsorption process. Under optimal conditions (initial concentration of pesticide 10 mg L−1, pH = 7, and contact time of 10 min), 99.6% of IMCP was effectively removed, indicating the excellent ability of the adsorbent to adsorb this insecticide from aqueous solutions. [ABSTRACT FROM AUTHOR]

Reliable and precise quantification of 25‐hydroxyvitamin D3 in clinical samples is vital because vitamin D3 deficiency lead to several disorders, such as mental illness, osteoporosis, and coronavirus disease. Herein, we report the fabrication of a novel electrochemical aptasensor using a nanocomposite, including reduced graphene oxide, pyrrole, and l‐cysteine, for the sensitive detection of 25‐hydroxyvitamin D3. Subsequently, the aptamer of 25‐hydroxyvitamin D3 was immobilized on the surface of the modified electrode. Differential pulse voltammetry signals were utilized for studying the binding and measurement of 25‐hydroxyvitamin D3 based on the oxidation peak. Under the optimum conditions, the designed electrochemical aptasensor exhibited a linear detection range of 0.001–150 nM, with a limit of detection of 0.006 nM. Furthermore, the proposed aptasensor selectively detected 25‐hydroxyvitamin D3 compared to other analogs. Moreover, this aptasensor was successfully applied for the detection of 25‐hydroxyvitamin D3 in human serum samples, which were quantified by the enzyme‐linked immunosorbent assay method. The acceptable recoveries of 82.67%–111.07% demonstrated that this proposed electrochemical aptasensor can be a promising alternative for clinical methods of vitamin D determination. [ABSTRACT FROM AUTHOR]

Reliable and precise quantification of 25‐hydroxyvitamin D3 in clinical samples is vital because vitamin D3 deficiency lead to several disorders, such as mental illness, osteoporosis, and coronavirus disease. Herein, we report the fabrication of a novel electrochemical aptasensor using a nanocomposite, including reduced graphene oxide, pyrrole, and l‐cysteine, for the sensitive detection of 25‐hydroxyvitamin D3. Subsequently, the aptamer of 25‐hydroxyvitamin D3 was immobilized on the surface of the modified electrode. Differential pulse voltammetry signals were utilized for studying the binding and measurement of 25‐hydroxyvitamin D3 based on the oxidation peak. Under the optimum conditions, the designed electrochemical aptasensor exhibited a linear detection range of 0.001–150 nM, with a limit of detection of 0.006 nM. Furthermore, the proposed aptasensor selectively detected 25‐hydroxyvitamin D3 compared to other analogs. Moreover, this aptasensor was successfully applied for the detection of 25‐hydroxyvitamin D3 in human serum samples, which were quantified by the enzyme‐linked immunosorbent assay method. The acceptable recoveries of 82.67%–111.07% demonstrated that this proposed electrochemical aptasensor can be a promising alternative for clinical methods of vitamin D determination. [ABSTRACT FROM AUTHOR]

Liposomes have been attracted considerable attention as phospholipid spherical vesicles, over the past 40 years. These lipid vesicles are valued in biomedical application due to their ability to carry both hydrophobic and hydrophilic agents, high biocompatibility and biodegradability. Until now, various methods have been used for the synthesis of liposomes and the numerous modifications have been performed to improve liposomes characteristics such as surface charge, size, number of their layers, and length of circulation in biological fluids. This article provides an overview of the significant advances in synthesis of liposomes via active or passive drug loading methods, as well as describes some strategies developed to fabricate their targeted formulations to overcome limitations of the "first-generation" liposomes. [ABSTRACT FROM AUTHOR]

Although the therapeutic effect of liposomal arsenic trioxide arsenic trioxide (ATO) in the treatment of solid tumours has been confirmed, its dose-limiting loading is a challenging issue. To solve the problems in the preparation of liposomal ATO, different loading strategies were evaluated and compared. In addition, liposomes decorated with anti-nucleolin aptamers were developed as a novel formulation for targeted delivery with high loading efficiency and sustained releasing property in order to treat solid tumours. The liposomes were prepared by a thin-film method exploiting the passive loading strategy of Co(II) hydrogen arsenite (CHA). The structural characteristics of the liposomes were also investigated by Fourier transform infra-red spectroscopy (FT-IR), dynamic light scattering (DLS), zeta potentiometry, field emission scanning electron microscopy (FESEM), and Energy Dispersive X-ray Diffraction (EDX) techniques. To evaluate the potential cytotoxicity of this liposomal drug vehicle in vitro, MTT assay was performed on HT-29 cancer cell line. The results showed that the synthesised liposomes loaded with CHA exhibited high entrapment efficiency (77%). MTT assays showed a significant difference between the percentage of viable cells when HT −29 cells were treated with free ATO and liposomal formulation which can be corresponded to the sustained release of the drug from the liposomes. The results of this study may lead to a promising strategy for the effective treatment of solid tumours. [ABSTRACT FROM AUTHOR]

Cancer is a broad term used to describe a group of diseases that have more than 270 types. Today, due to the suffering of patients from the side effects of existing methods in the treatment of cancer such as chemotherapy and radiotherapy, the employment of targeted methods in the treatment of this disease has been received much consideration. In recent years, nanoparticles have revolutionized in the treatment of many diseases such as cancer. Among these nanoparticles, liposomes are more considerable. Active targeted liposomes show an important role in the selective action of the drug on cancer cells. Until now, a variety of anti-cancer agents have been reported for targeted delivery to cancer cells using liposomes. The results of in vitro and studies in vivo have been shown that selective action of the targeted liposomes is increased with reduced side effects and toxicity compared with free drugs or non-targeted liposomes. This systematic review expresses the reports of this type of drug delivery system. Search terms were searched through several online databases including PubMed, Scopus, and Science Direct from 1990 to 2019 and the quality evaluation was performed. Out of 11,676 published articles, 196 articles met the inclusion criteria. The current report reviews developments in the liposomes targeted with aptamer, transferrin, folate, and monoclonal antibodies. [ABSTRACT FROM AUTHOR]

Introduction: Various types of toothpastes are claimed to be able to improve initial enamel caries. This study compared the effect of fluoride gel and two toothpastes on remineralization of initial caries lesions in primary teeth. Materials and Methods: A total of sixty-four sound extracted primary canine were immersed in demineralizing solution at 37°C for 96 h to produce artificial caries in vitro. Enamel pieces (3 × 3 × 5 mm) were prepared from each tooth and mounted in self cure acrylic blocks. The specimens were randomly assigned to four groups (n = 16) based on treatment agent (fluoride gel, Chitodent toothpaste, ReminPro toothpaste, no treatment as control) and underwent a pH cycling model for 10 days. Vickers microhardness (VH) was measured before and after treatment. Data was analyzed using analysis of variance and paired t-test by SPSS 18 (P < 0.05). Results: No significant difference was found in VH between groups at baseline (fluoride group: 265.9 ± 44.8, Chitodent group: 282.6 ± 34.6, ReminPro group: 266.5 ± 26.6, control: 272.7 ± 32.5; P = 0.516). Microhardness significantly increased after exposure to ReminPro toothpaste (VH change: 24.1%, P < 0.001) and fluoride gel (VH change: 10.9%, P = 0.046), but no significant changes were observed in Chitodent (VH change: 2.8%, P = 0.635) and control (VH change: - 2.2%, P = 0.181) groups. Conclusion: ReminPro toothpaste might be effective in remineralizing initial carious lesions of primary teeth. [ABSTRACT FROM AUTHOR]

Background: Vitamin and mineral deficiencies are prevalent globally, and extensive efforts have been made to assess their status. Most traditional methods are expensive and time-consuming; therefore, developments of rapid, simple, specific, and sensitive methods for the assessment of vitamins and minerals in biological samples are of high importance in research. Aptamers are synthetic nucleic acid single-stranded DNA or RNA that can be synthesized in vitro. They can be engineered to be analyte-specific and have been suggested as a substitute for monoclonal antibodies, due to their high sensitivity and affinity. In addition, aptamers can be chemically synthesized and readily modified for use as biosensors. These features make aptamers a promising tool for the detection of biological analytes. In this review, we provide an overview of the potential use of aptamer-based biosensors. Methods: Search terms were conducted on several online databases, including Google Scholar, PubMed, Scopus, and Science Direct from January 2000 to August 2019. Eligibility criteria were used and quality evaluation was performed. Following the review of 4349 articles, 39 articles met the inclusion criteria. Results: Aptasensors have recently been developed for the detection of vitamins by using optical methods, with a detection range from 74 pM to 204 pM, and lower limit of detection of 2.4 pM. Both electrochemical and optical methods have been used for detection of minerals, however electrochemical methods show a wider linear range and lower detection limits compared to optical methods with a wide linear range from 0.2 fM to 1.0 mM and limit of detection of 14.7 fM. Conclusion: The current report reviews recent developments in aptamer-based biosensors for detection of vitamins and minerals. Studies have shown that aptasensors' properties are suitable for the quantification of vitamins and minerals with high sensitivity, affinity, and specificity. Nevertheless, the limitations and future directions of aptamers require further research and new technological innovation. [ABSTRACT FROM AUTHOR]

Abstract: In this research, the possibility of simultaneous removal of lead, cadmium and copper divalent ions from water samples through the use of Sepia pharaonis endoskeleton powder (SPEB) as bio‐material, was investigated. The bio‐sorbent was characterised by Fourier transform infrared spectrum (FT‐IR), atomic force microscopy (AFM) and X‐ray fluorescence (XRF). The different factors affecting the bio‐sorption process were studied. Langmuir and Freundlich isotherm models were applied to analyse the experimental data. The kinetic studies showed that the pseudo‐second order model kinetics were compatible with the investigated systems. It was found that under optimal conditions, this bio‐sorbent was efficient in the uptake of these heavy metal ions from both mono and multi‐metal solutions, and high removal percentages were achieved. This study verified the potential ability of SPEB as an efficient natural adsorbent for removal of Pb(II), Cd(II) and Cu(II) ions from river, tap and mineral water samples. [ABSTRACT FROM AUTHOR]

Reliable and precise quantification of 25-hydroxyvitamin D 3 in clinical samples is vital because vitamin D 3 deficiency lead to several disorders, such as mental illness, osteoporosis, and coronavirus disease. Herein, we report the fabrication of a novel electrochemical aptasensor using a nanocomposite, including reduced graphene oxide, pyrrole, and l-cysteine, for the sensitive detection of 25-hydroxyvitamin D 3 . Subsequently, the aptamer of 25-hydroxyvitamin D 3 was immobilized on the surface of the modified electrode. Differential pulse voltammetry signals were utilized for studying the binding and measurement of 25-hydroxyvitamin D 3 based on the oxidation peak. Under the optimum conditions, the designed electrochemical aptasensor exhibited a linear detection range of 0.001-150 nM, with a limit of detection of 0.006 nM. Furthermore, the proposed aptasensor selectively detected 25-hydroxyvitamin D 3 compared to other analogs. Moreover, this aptasensor was successfully applied for the detection of 25-hydroxyvitamin D 3 in human serum samples, which were quantified by the enzyme-linked immunosorbent assay method. The acceptable recoveries of 82.67%-111.07% demonstrated that this proposed electrochemical aptasensor can be a promising alternative for clinical methods of vitamin D determination., (© 2023 International Union of Biochemistry and Molecular Biology, Inc.)