Chitosan based nanoformulation expressing miR-155 as a promising adjuvant to enhance Th1-biased immune responses.

BACKGROUND AND AIM: MiR-155 could act as a key modulator of different aspects of immune system including Th1 responses. In this study, we designed chitosan nanoparticles containing miR-155-expressing plasmid and explored their effects as an adjuvant to enhance Th1 responses for potential future application against intracellular pathogens. METHODS: Nanoparticles were formulated by complex coacervation method and characterized for physicochemical and functional characteristics. Transfection efficiency in Raw 264.7 cells, effects on miR-155 target genes and NO production were evaluated. The prepared nanoparticles were co-administered as an adjuvant with ovalbumin to immunize mice and finally production of IFN-γ and IL-4 were measured by ELISA in splenocyte recall responses. RESULTS: The prepared nanoparticles had the mean size of 244 nm and zeta potential of +17 mV, respectively. Electrophoresis analysis indicated the high capability of nanoparticles to protect the plasmid from DNaseI degradation. Furthermore, nanoparticles showed an appropriate transfection efficiency in Raw 264.7 cells and could downregulate the expression of miR-155 target genes and also upregulate NO production. In vivo immunization examinations revealed successful shift of T cell responses toward Th1. CONCLUSION: Our data suggests the high potential of chitosan nanoparticles containing miR-155-expressing plasmid as an adjuvant for significantly enhanced Th1-biased immune responses upon immunization with a given antigen.

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.

Microfluidic platform for synthesis and optimization of chitosan-coated magnetic nanoparticles in cisplatin delivery.

In this study, magnetic core/chitosan shell Nanoparticles (NPs) containing cisplatin were synthesized via cisplatin complexation with tripolyphosphate as the chitosan crosslinker using two different procedures: a conventional batch flow method and a microfluidic approach. An integrated microfluidic device composed of three stages was developed to provide precise and highly controllable mixing. The comparison of the results revealed that NPs synthesized in microchannels were monodisperse 104 ±â€¯14.59 nm (n = 3) in size with optimal morphological characteristics, whereas polydisperse 423 ±â€¯53.33 nm (n = 3) nanoparticles were obtained by the conventional method. Furthermore, cisplatin was loaded in NPs without becoming inactivated, and the microfluidic technique demonstrated higher encapsulation efficiency, controlled release, and consequently lower IC50 values during exposure to the A2780 cell line proving that microfluidic synthesized NPs were able to enter the cells and release the drug more efficiently. The developed microfluidic platform presents valuable features that could potentially provide the clinical translation of NPs in drug delivery.

An investigation of affecting factors on MOF characteristics for biomedical applications: A systematic review.

Metal-organic frameworks (MOFs) are a fascinating class of crystalline porous materials composed of metal ions and organic ligands. Due to their attractive properties, MOFs can potentially offer biomedical field applications, such as drug delivery and imaging. This study aimed to systematically identify the affecting factors on the MOF characteristics and their effects on structural and biological characteristics. An electronic search was performed in four databases containing PubMed, Scopus, Web of Science, and Embase, using the relevant keywords. After analyzing the studies, 20 eligible studies were included in this review. As a result, various factors such as additives and organic ligand can influence the size and structure of MOFs. Additives are materials that can compete with ligand and may affect the nucleation and growth processes and, consequently, particle size. The nature and structure of ligand are influential in determining the size and structure of MOF. Moreover, synthesis parameters like the reaction time and initial reagents ratio are critical factors that should be optimized to regulate the size and structure. Of note is that the nature of the ligand and using a suitable additive can control the porosity of MOF. The more extended ligands aid in forming large pores. The choice of metallic nodes and organic ligand, and the MOF concentration are important factors since they can determine toxicity and biocompatibility of the final structure. The physicochemical properties of MOFs, such as hydrophobicity, affect the toxicity of nanoparticles. An increase in hydrophobicity causes increased toxicity of MOF. The biodegradability of MOF, as another property, depends on the organic ligand and metal ion and environmental conditions like pH. Photocleavable ligands can be served for controlled degradation of MOFs. Generally, by optimizing these affecting factors, MOFs with desirable properties will be obtained for biomedical applications.

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.

Development of Carbon Nanostructured Based Electrochemical Sensors for Pharmaceutical Analysis.

Pharmaceutical drugs play an important role in human life since they caused a revolution in human health. Notably, their administration to a living organism helps body to stay healthy. Commonly, they are employed to diagnose, prevent, or treat and cure a disease via a biological effect on a human body. Administration of impurity-free and adequate amounts of pharmaceutical compounds would be beneficial. Therefore, the quantity and purity of the substances in pharmaceutical compounds are continuously monitored during drug manufacturing with various chemical or instrumental analysis techniques. The possibility of impurities development and chemical or quantity changes of active drug species at various stages (namely during production, transportation or storage) makes them redundant and risky for human health. So, sensitive and accurate analysis methods for qualitative and quantitative analysis are highly demanded by pharmaceutical companies and medical centers. The present mini review emphasizes on application of carbon based modified electrodes in health care and pharmaceutical analysis. Electrochemical determination of drugs employing carbon nanostructured modified electrodes will be reviewed and their advantages and disadvantages will be mentioned.

Functionalisation of carbon nanotubes by methotrexate and study of synchronous photothermal effect of carbon nanotube and anticancer drug on cancer cell death.

Carboxylated functionalised multi-walled carbon nanotubes (f-MWCNT) were synthesised. Furthermore, folic acid (FA) and methotrexate (MTX) through ethylenediamine (ED) were attached to the surface of f-MWCNT to synthesise MWCNT-ED-FA and MWCNT-ED-MTX. Release studies of MTX as free drug and in MWCNT-ED-MTX were performed. These studies showed that MTX release rate from MWCNT-ED-MTX decreased in comparison with free MTX, which is due to the MTX attachment on the MWCNT. The anticancer effect of MWCNT-ED-FA and MWCNT-ED-MTX on the breast cancer cell line (MCF-7) was studied. Studies have shown that MWCNT-ED-MTX cytotoxicity is more than that of MWCNT-ED-FA, which is due to the presence of MTX. Furthermore, the anticancer effects of MWCNT-ED-FA and MWCNT-ED-MTX in the presence of infrared laser radiation on the MCF7 cell were studied. The experiments showed that in the presence of the laser, the cytotoxicities of MWCNT-ED-FA and MWCNT-ED-MTX were the same and increased in comparison with laser absence, which indicates that the photothermal effect is stronger than other factors and mask their effects. This effect can be related to laser radiation absorption by MWCNT and its conversion to heat which can induce cancer cell death. Targeting studies have shown that MWCNT-ED-FA is targeted to the cancer cells due to the presence of FA.

The Photothermal Effect of Targeted Methotrexate-Functionalized Multi-Walled Carbon Nanotubes on MCF7 Cells.

Our goal is to reduce the release rate of methotrexate (MTX) and increase cell death efficiency.Carboxylated multi-walled carbon nanotubes (MWCNT-COOH) were functionalized with MTX as a cytotoxic agent, FA as a targeting moiety and polyethylene amine (PEI) as a hydrophilic agent. Ultimately, MWCNT-MTX and MWCNT-MTX-PEI-FA were synthesized. Methotrexate release studies were conducted in PBS and cytotoxic studies were carried out by means of the MTT tassay. Methotrexate release studies from these two carriers demonstrated that the attachment of PEI-FA onto MWCNT-MTX reduces the release rate of methotrexate. The IC50 of MWCNT-MTX-PEI-FA and MWCNT-MTX have been calculated as follows: 9.89 ± 0.38 and 16.98 ± 1.07 µg/mL, respectively. Cytotoxic studies on MWCNT-MTX-PEI-FA and MWCNT-MTX in the presence of an IR laser showed that at high concentrations, they had similar toxicities due to the MWCNT's photothermal effect. Targeting effect studies in the presence of the IR laser on the cancer cells have shown that MWCNT-MTX-PEI-FA, MWCNT-MTX, and f-MWCNT have triggered the death of cancer cells by 55.11 ± 1.97%, 49.64 ± 2.44%, and 37 ± 0.70%, respectively. The release profile of MTX in MWCNT-MTX-PEI-FA showed that the presence of PEI acts as a barrier against release and reduces the MTX release rate. In the absence of a laser, MWCNT-MTX-PEI-FA exhibits the highest degree of cytotoxicity. In the presence of a laser, the cytotoxicity of MWCNT-MTX and MWCNT-MTX-PEI-FA has no significant difference. Targeting studies have shown that MWCNT-MTX-PEI-FA can be absorbed by cancer cells exclusively.

Formulation Optimization and Assessment of Dexamethasone Orally Disintegrating Tablets Using Box-Behnken Design.

The aim of this study was to prepare orally disintegrating tablets (ODTs) containing dexamethasone (DEX) by direct compression method with sufficient hardness and rapid disintegration time. In order to save time, money, and human resources in designing and improvement of formulation, the statistical software Design Expert is used. Box-Behnken response surface methodology was applied to evaluate and optimize the effects of concentrations of three excipients, Kollidon CL-SF (X1), Pearlitol SD200 (X2), and Prosolv SMCC (X3) as independent factors on four responses: percentage of drug released after 5 min, disintegrating time, hardness, and friability. Thirteen formulations offered by the Box-Behnken design were prepared by direct compression method and ultimate weight of 200 mg, while the amount of DEX was 4 mg. All formulations were characterized for parameters such as diameter, hardness, weight, thickness, friability, and disintegration time. Following the statistical results, the effects of independent variables on responses were evaluated and the optimum formulation regarding acceptable responses consisted of 15% Kollidon, 39.66% Pearlitol, and 7.5% Prosolv which showed 95.28% release of the drug after 5 min, disintegrating time of 30 sec, 6.1 kg hardness, and 0.12% of friability with an acceptable taste as the optimized formulation.

Study and Optimization of The Necessary Conditions for The Sensitive Determination of The Lead Ion by a Modified Carbon Paste Electrode in Environmental Water Samples.

Rapid and facile preparation of the cheap modified electrode materials is an important parameter in development of the efficient electrochemical sensor for industrial scale production and mass-market usage. In the present work, the carbon paste electrode modified with multi-walled carbon nanotubes (MWCNTs) was prepared for sensitive determination of lead (Pb) ion in the presence of bismuth (Bi) ion due to synergetic effect of carbon nano-materials and Bi on the voltammetric response. Investigations showed that in presence of Bi ion degassing of the test solution is not needed. Supporting electrolyte, required Bi concentration and accumulation time and potential were optimized for differential pulsed anodic stripping voltammetric tests. Under optimized conditions, modified carbon paste electrode showed sensitive voltammetric response in the range of 0.1-10 µM toward Pb ion. Moreover, efficiency of the developed method was evaluated for the determination of Pb ion in several water samples. The obtained recovery results of 92-97 % revealed good agreement between responses of this sensor and common spectroscopies techniques for the Pb ion analysis. The optimized system has high efficiency in reproducibility and repeatability of the results and applicability for the analysis of the various environmental water samples.

Superparamagnetic graphene oxide-based dispersive-solid phase extraction for preconcentration and determination of tamsulosin hydrochloride in human plasma by high performance liquid chromatography-ultraviolet detection.

In the present study, superparamagnetic graphene oxide-Fe3O4 nanocomposites were successfully prepared by a modified impregnation method (MGOmi) and their application as a sorbent in the magnetic-dispersive solid phase extraction (M-dSPE) mode to the preconcentration and determination of tamsulosin hydrochloride (TMS) in human plasma was investigated by coupling with high performance liquid chromatography-ultraviolet detection (HPLC-UV). The structure, morphology and magnetic properties of the prepared nanocomposites were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and vibrating sample magnetometry (VSM). Some factors affecting the extraction efficiency, including the pH value, amount of sorbent, extraction time, elution solvent and its volume, and desorption time were studied and optimized. Magnetic nanocomposites plasma extraction of TMS following HPLC analyses showed a linear calibration curve in the range of 0.5-50.0ngmL-1 with an acceptable correlation coefficient (R2=0.9988). The method was sensitive, with a low limit of detection (0.17ngmL-1) and quantification (0.48ngmL-1). Inter- and intra-day precision expressed as relative standard deviation (n=3) and the preconcentration factor, were found to be 5.6-7.2%, 2.9-4.2% and 10, respectively. Good recoveries (98.1-101.4%) with low relative standard deviations (4.2-5.0%) indicated that the matrices under consideration do not significantly affect the extraction process. Due to its high precision and accuracy, the developed method may be a HPLC-UV alternative with M-dSPE for bioequivalence analysis of TMS in human plasma.

Design and Evaluation of Ocular Controlled Delivery System for Diclofenac Sodium.

Diclofenac sodium as ophthalmic dosage form is used for the treatment of the pain, swelling and redness of patients' eyes recovering from cataract surgery; however, it faces the bioavailability limitation of eye drops due to effective protective mechanisms and corneal barrier functions in the eyes. Therefore, this investigation was aimed to develop ocular film formulations to achieve controlled drug release. Drug films were prepared using polymers, namely hydroxypropyl methylcellulose (HPMC) and polyvinyl pyrrolidone (PVP), Eudragit RL PO, and Eudragit RS PO by solvent casting method considering parameters such as drug: polymer ratio, different polymer combinations as well as plasticizer effect. Ocular films were evaluated for various physicochemical parameters such as physical characters, film thickness, uniformity of weight, drug content, swelling index, mucoadhesion time and in-vitro release study. Ocular films complied with all physicochemical parameters underwent in-vitro release study. Finally, the film formulation with HPMC: Eudragit RS PO 1:1 ratio, Drug: Polymer ratio 1:45 and glycerin as plasticizer showed controlled and prolonged release following the zero order and non-Fickian transport.

Voltammetric Behavior and Determination of Trace Amounts of Omeprazole Using an Edge-plane Pyrolytic Graphite Electrode.

The voltammetric performance of edge-plane pyrolytic graphite (EPG) electrode via adsorptive stripping voltammetry was investigated for study of the electrochemical behavior of omeprazole (OMZ) in aqueous solution. The results revealed that the oxidation of OMZ is an irreversible pH-dependent process that proceeds with the transfer of one electron and one proton in an adsorption-controlled mechanism. The determination conditions, such as the pH values of the supporting electrolyte, accumulation time and scan rate were optimized. Simplicity, high reproducibility and low detection limit (3 nM) of the electrode response as well as wide linear range (0.01 to 4.0 µM) can be stated as significant features of this electrode. The EPG electrode was successfully applied for the determination of OMZ in pharmaceutical formulations and satisfactory results were obtained.

Voltammetric studies of sumatriptan on the surface of pyrolytic graphite electrode modified with multi-walled carbon nanotubes decorated with silver nanoparticles.

Multi-walled carbon nanotube decorated with silver nanoparticles (AgNPs-MWCNT) is used as an effective strategy for modification of the surface of pyrolytic graphite electrode (PGE). This modification procedure improved colloidal dispersion of the decorated MWCNTs in water, affording uniform and stable thin films for altering the surface properties of the working electrode. Robust electrode for sensing applications is obtained in a simple solvent evaporation process. The electrochemical behavior of sumatriptan (Sum) at the bare PGE and AgNPs-MWCNT modified PGE is investigated. The results indicate that the AgNPs-MWCNT modified PGE significantly enhanced the oxidation peak current of Sum. A remarkable enhancement in microscopic area of the electrode together with strong adsorption of Sum on the surface of the modified electrode resulted in a considerable increase in the peak current of Sum. Experimental parameters, such as scan rate, pH, accumulation conditions and amount of the modifier used on the PGE surface are optimized by monitoring the CV responses toward Sum. It is found that a maximum current response can be obtained at pH 7.4 after accumulation at open circuit for 150 s. Further experiments demonstrated that the oxidative peak currents increased linearly with Sum concentration in the range of 8.0 x 10(-8)-1.0 x 10(-4)mol L(-1) with a detection limit of 4.0 x 10(-8) mol L(-1). The modified electrode showed high sensitivity, selectivity, long-term stability and remarkable voltammetric reproducibility in response to Sum. These excellent properties make the prepared sensor suitable for the analysis in pharmaceutical and clinical preparations. The modified electrode was successfully applied for the accurate determination of trace amounts of Sum in pharmaceutical preparations.