Synthesis of Zeolitic imidazolate frameworks-8@ layered double hydroxide polyhedral nanocomposite with designed porous voids as an effective carrier for anti-cancer drug-controlled delivery.

In nanotechnology, compounds containing metal materials are used in pharmaceutical sciences. The main purpose of this research was to introduce a novel method to control the amount of zeolite imidazolate framework (ZIF) in water by forming a protective layer such as layered double hydroxide (LDH). Firstly, ZIF was synthesised as the nucleus of the nanocomposite, and then LDH was formed by in situ synthesis as a protective layer. Scanning electron microscope, Fourier-transform infrared spectroscopy, X-Ray Diffraction, and Brunauer, Emmett and Teller techniques were used to determine (ZIF-8@LDH chemical structure and morphology. Our findings revealed that the ZIF-8@LDH-MTX complex could interact with carboxyl groups and trivalent cations by creating a bifurcation bridge, clarity, and high thermal stability. The antibacterial test indicated that ZIF-8@LDH was able to inhibit pathogenic growth. 2,5-Diphenyl-2H-Tetrazolium Bromide assay results showed that ZIF-8@LDH alone had no notable cytotoxic effect on Michigan Cancer Foundation-7 (MCF-7) cancer cells. However, the cytotoxicity rate was significantly increased in treated MCF-7 cells with ZIF-8@LDH-MTX compared to that of treated cells with methotrexate alone, which can be reasoned by the protection of drug structure and increasing its permeability. The drug release profile was constant at pH = 7.4. All findings indicated that the ZIF-8@LDH complex could be considered a newly proposed solution for effective anti-cancer drug delivery.

Evaluating the effects of zeolitic imidazolate framework and Eremostachys binalodensis extract on Candida albicans and Streptococcus mutans biofilms.

Biofilms represent longstanding challenges to oral health care. Candida albicans and Streptococcus mutans are the common pathogens forming biofilms. The growing resistance to and the adverse effects of antibiotics limit their usage and raise the need for novel approaches. Herbal extracts have emerged as efficient choices with lower costs and fewer adverse effects. Metal frameworks have captivated interest due to their high surface area, special biocompatibility, and non-toxicity. The effects of zeolitic imidazolate frameworks/layered double hydroxide (ZIF/LDH) on fungal infections and the potential effects of Eremostachys binalodensis on bacteria encouraged the researchers to evaluate the effect of ZIF/LDH, E. binalodensis, and their combination on C. albicans and S. mutans biofilms. ZIF/LDH nanocomposite was synthesized and characterized using scanning electron microscopy, Fourier transform infrared spectra, and X-ray diffraction to assess morphology and chemical structure. Methanol extracts of the areal parts of E. binalodensis were obtained by Soxhlet extraction. The microdilution tests and biofilm crystal violet staining were applied. Concentrations of 2.048 and 4.096 mg/ml E. binalodensis prevented C. albicans and S. mutans biofilm formation. The combination of ZIF/LDH + E. binalodensis prevented C. albicans and S. mutans biofilm formation. This research suggests the use of E. binalodensis-loaded ZIF/LDH nanocomposites for removing biofilms.

Design and synthesis of silver nanoparticle anchored poly(ionic liquid)s mesoporous for controlled anticancer drug delivery with antimicrobial effect.

Owing to the importance of drug delivery, the synthesis of advanced nanomaterials for targeted drug delivery plays a considerable role in medical treatment. One of the most prominent nanomaterials is PIL, which is used as controlled anticancer drug delivery and significantly improves the half-life and antitumor effect. In this study, a stable and effective drug carrier containing silver nanoparticles was reported for the drug delivery with an antimicrobial effect, and the capability of the drug carrier . PILP was synthesized by radical polymerization, and silver nanoparticles were anchored into PIL voids by in-situ reduction, which developed the adsorption antimicrobial effect and capability of the drug carrier. The synthesized nanocomposite was characterized. The Ag-PILP nanocomposite showed antibacterial activityagainst both E. coli and S. aureus with a MIC of 256 µg/mL, and bactericidal activity against E. coli and S. aureus strains with a MBC of 256 and 512 µg/mL, respectively.

Synthesis and application of magnetic@layered double hydroxide as an anti-inflammatory drugs nanocarrier.

BACKGROUND: Magnetic nanocomposites with a core-shell nanostructure have huge applications in different sciences especially in the release of the drugs, because of their exclusive physical and chemical properties. In this research, magnetic@layered double hydroxide multicore@shell nanostructure was synthesized by the facile experiment and is used as novel drug nanocarrier. METHODS: Magnetic nanospheres were synthesized by a facile one-step solvothermal route, and then, layered double hydroxide nanoflakes were prepared on the magnetic nanospheres by coprecipitation experiment. The synthesized nanostructures were characterized by FTIR, XRD, SEM, VSM, and TEM, respectively. After intercalation with Ibuprofen and Diclofenac as anti-inflammatory drugs and using exchange anion experiment, the basal spacing of synthesized layered double hydroxides was compared with brucite nanosheets from 0.48 nm to 2.62 nm and 2.22 nm, respectively. RESULTS: The results indicated that Ibuprofen and Diclofenac were successfully intercalated into the interlay space of LDHs via bridging bidentate interaction. In addition, in-vitro drug release experiments in pH 7.4, phosphate-buffered saline (PBS) showed constant release profiles with Ibuprofen and Diclofenac as model drugs with different lipophilicity, water solubility, size, and steric effect. CONCLUSION: The Fe3O4@LDH-ibuprofen and Fe3O4@LDH-diclofenac had the advantage of the strong interaction between the carboxyl groups with higher trivalent cations by bridging bidentate, clarity, and high thermal stability. It is confirmed that Fe3O4@LDH multicore-shell nanostructure may have potential application for constant drug delivery.

Layered double hydroxide nanoparticles as an appealing nanoparticle in gene/plasmid and drug delivery system in C2C12 myoblast cells.

Gene and drug delivery systems need crucial update in the issue of nanocarriers. Layered double hydroxides (LDHs) are known as biocompatible inorganic lamellar nanomaterials with versatile properties. In the present study, Zn/Al-LDH nanoparticle was synthesized and characterized by FTIR, XRD, SEM, TEM and Zeta potential tests and then intercalated with valproate and methyldopa by co-precipitation and ion exchange methods. These nanocarriers were applied as high activity nanolayers-based delivery systems. On the other hand, Zn/Al-LDH + plasmid/gene (pCEP4/Cdk9) evaluated on C2C12 myoblast cells. Co-operation loading indicated high efficiency of sorting and release of drugs. Additionally, the Real-Time PCR and Western blotting results for plasmid-gene (pCEP4/Cdk9) delivery showed that Zn/Al-LDH nanoparticles can be used as an effective carrier in cellular uptake and release of genes for gene therapy. Easy and cost-effective production of Zn/Al-LDH nanoparticles proposed them as potential alternatives for the traditional routs of drug/gene delivery.

Synthesis of layered zinc hydroxide intercalated with dodecyl sulfate organic-inorganic hybrid nanocomposite as a fiber coating for the headspace solid-phase microextraction of aromatic hydrocarbons from water.

We describe the synthesis of a layered zinc hydroxide-dodecyl sulfate organic-inorganic hybrid nanocomposite as a new solid-phase microextraction fiber. The fiber coating can be prepared easily in a short time and the reaction is at room temperature; it is mechanically stable and exhibits relatively high thermal stability. The synthesized layered zinc hydroxide-dodecyl sulfate nanocomposite was successfully prepared and immobilized on a stainless steel wire and evaluated for the extraction of aromatic compounds from aqueous sample solutions in combination with gas chromatography and mass spectrometry. The method yields good results for some validation parameters. Under optimum conditions (extraction time: 15 min, extraction temperature: 50°C, desorption time: 1 min, desorption temperature: 250°C, salt concentration: 0.5 g/mL), the limit of detection and dynamic linear range were 0.69-3.2 ng/L and 10-500 ng/L, respectively. The method was applied to the analyses of benzene, toluene, ethylbenzene, and o-, p-, and m-xylenes in two real water samples collected from the Aji river and Mehran river, Tabriz, Iran. Under optimum conditions, the repeatability and reproducibility for one fiber (n = 3), expressed as the relative standard deviation, was 3.2-7.3% and 4.2-11.2% respectively. The fibers are thermally stable and yield better recoveries than conventional methods of analysis.

Fabrication of polyaniline-coated halloysite nanotubes by in situ chemical polymerization as a solid-phase microextraction coating for the analysis of volatile organic compounds in aqueous solutions.

We have synthesized an organic-inorganic polyaniline-halloysite nanotube composite by an in situ polymerization method. This nanocomposite is immobilized on a stainless-steel wire and can be used as a fiber coating for solid-phase microextraction. It was found that our new solid-phase microextraction fiber is an excellent adsorbent for the extraction of some volatile organic compounds in aqueous samples in combination with gas chromatography and mass spectrometry. The coating can be prepared easily, is mechanically stable, and exhibits relatively high thermal stability. It is capable of extracting phenolic compounds from water samples. Following thermal desorption, the phenols were quantified by gas chromatography with mass spectrometry. The effects of extraction temperature, extraction time, sample ionic strength, stirring rate, pH, desorption temperature and desorption time were studied. Under optimal conditions, the repeatability for one fiber (n = 5), expressed as the relative standard deviation, is between 6.2 and 9.1%. The detection limits range from 0.005 to 4 ng/mL. The method offers the advantage of being simple to use, with a shorter analysis time, lower cost of equipment and higher thermal stability of the fiber in comparison to conventional methods of analysis.

Synthesis of a metal-organic framework confined in periodic mesoporous silica with enhanced hydrostability as a novel fiber coating for solid-phase microextraction.

A metal-organic framework/periodic mesoporous silica (MOF-5@SBA-15) hybrid material has been prepared by using SBA-15 as a matrix. The prepared MOF-5@SBA-15 hybrid material was then deposited on a stainless-steel wire to obtain the fiber for the solid-phase microextraction of phenolic compounds. Modifications in the metal-organic framework structure have proven to improve the extraction performance of MOF/SBA-15 hybrid materials, compared to pure MOF-5 and SBA-15. Optimum conditions include an extraction temperature of 75°C, a desorption temperature of 260°C, and a salt concentration of 20% w/v. The dynamic linear range and limit of detection range from 0.1-500 and from 0.01-3.12 ng/mL, respectively. The repeatability for one fiber (n = 3), expressed as relative standard deviation, is between 4.3 and 9.6%. The method offers the advantage of being simple to use, rapid, and low cost, the thermal stability of the fiber, and high relative recovery (compared to conventional methods) represent additional attractive features.

Nanoscale-supported heteropoly acid as a new fiber coating for solid-phase microextraction coupled with gas chromatography-mass spectrometry.

In the present study, 12-tungstophosphoric (PW) acid as heteropoly acid, supported on silica-coated γ-Fe2O3 nanoparticles (NPs), was used as a new fiber coating for solid-phase microextraction (SPME). The γ-Fe2O3@SiO2-PW nanocomposite with high surface area was synthesized and characterized by SEM and FT-IR. The prepared nanocomposite was immobilized on a stainless steel wire for fabrication of the SPME fiber. The fiber was evaluated for the extraction of some phenolic compounds (PCs) from water sample in combination with gas chromatography-mass spectrometry (GC-MS). A one-at-a-time optimization strategy was applied for optimizing the important extraction parameters such as extraction temperature, extraction time, ionic strength, stirring rate, pH, and desorption temperature and time. In optimum conditions, the repeatability for one fiber (n=3), expressed as relative standard deviation (R.S.D. %), was between 4.8% and 9.6% for the test compounds. The detection limits for the studied compounds were between 0.004 and 0.05 pg mL(-1). The developed method offers the advantage of being simple to use, with shorter analysis time, lower cost of equipment, thermal stability of fiber and high relative recovery in comparison to conventional methods of analysis.

Synthesis of carbon nanotube/layered double hydroxide nanocomposite as a novel fiber coating for the headspace solid-phase microextraction of phenols from water samples.

In this research, a carbon nanotube/layered double hydroxide nanocomposite was synthesized by an in situ growth route by electrostatic force. The prepared carbon nanotube/layered double hydroxide nanocomposite was successfully prepared and deposited on a stainless-steel wire for the fabrication of the solid-phase microextraction fiber. The fiber was evaluated for the extraction of phenolic compounds from water samples. Analytical merits of the method, under optimum conditions (extraction temperature: 75°C, extraction time: 30 min, desorption time: 2 min, desorption temperature 260°C, salt concentration: 10% w/v) are 0.01-300 ng/mL for the linear dynamic range and 0.005-0.08 for the limit of detection. In optimum conditions, the repeatability for one fiber (n = 3), expressed as relative standard deviation, was between 6.5 and 9.9% for the phenolic compounds.

Polypyrrole-montmorillonite nanocomposite as sorbent for solid-phase microextraction of phenolic compounds in water.

A fiber-coated polypyrrole-montmorillonite nanocomposite was prepared for solid-phase microextraction. The fiber coating can be prepared easily; it is mechanically stable and exhibits relatively high thermal stability. The prepared fiber was evaluated for the extraction of some phenolic compounds from aqueous sample solutions by gas chromatography-mass spectrometry. The effects of the extraction and desorption parameters including extraction time, extraction temperature, stirring rate, ionic strength, pH and desorption temperature and time have been studied. At optimum conditions, the repeatability for one fiber (n = 5), expressed as % relative standard deviation was between 6.5 and 7.8% for the phenolic compounds. The detection limits for the studied phenolic compounds were between 0.05-1.3 ng/mL. The developed method offers the advantage of being simple to use, with shorter analysis time, lower cost, thermal stability of the fibers, and high relative recovery in comparison to conventional methods of analysis.

Effects of silver nano-particles on sperm parameters, number of Leydig cells and sex hormones in rats.

BACKGROUND: Nano-particles are extensively employed in most industries. Several studies have been started to explore the probable detrimental effects of nano-particles on human reproduction. However, there is insufficient and controversially evident of effects of silver nano-particles on sperm parameters and other reproductive indices. OBJECTIVE: Investigation of the effects of silver nano-particles on sperm parameters, sex hormones and Leydig cells in rat as an experimental model. MATERIALS AND METHODS: In this experimental study, 75 male prepubertal Wistar rats were categorized in five groups including control group and 4 experimental groups (n=15 in each group). The rats in the experimental groups were fed silver nano-particles (60 nm in dimension) with concentrations of 25, 50, 100, and 200 mg/kg/day. After 45 days (about one duration of spermatogenesis in rat), samples of blood were taken from the rats for testosterone, leuteinizing hormone (LH), and follicle stimulating hormone (FSH) assessments. Afterwards, the epididymis and the testis of each rat were dissected for analyzing sperm parameters and Leydig cells. RESULTS: The results demonstrated a statistically significant reduction in number of Leydig cells in experimental groups compared to control one. In addition, the data showed a reduction in testosterone and a rise in LH level which was more obvious in high doses (p<0.05); however, FSH level showed a reduction but it was not statistically significant. A significant decrease was also found in sperm motility and normal sperm morphology in the experimental groups compared to the control one. CONCLUSION: Our results demonstrated that silver nano-particles, in addition to interruption in functions of sex hormones, can diminish the number of Leydig cells and sperm parameter indices. It should be noted that the effects of nano-particles on reproductive indices are dose-dependent.

Three dimensionally honeycomb layered double hydroxides framework as a novel fiber coating for headspace solid-phase microextraction of phenolic compounds.

A new solid phase microextraction (SPME) fiber based on high-temperature three dimensionally honeycomb layered double hydroxide (TDH-LDH) material is presented. The fiber coating can be prepared easily, it is mechanically stable and exhibits relatively high thermal stability. This study shows that three dimensionally honeycomb layered double hydroxide generated porous morphology. The TDH-LDH material was tested for the extraction of some phenolic and polycyclic aromatic hydrocarbon compounds from aqueous sample solutions in combination with gas chromatography-mass spectrometry (GC-MS). The TDH-LDH fiber contains polar groups and its efficiency for non-polar polycyclic aromatic hydrocarbon compounds was lower than phenolic compounds. On the other hand, a high tendency towards the adsorption of polar phenolic compounds was observed for the proposed fiber. The effects of the extraction and desorption parameters including extraction temperature, extraction time, ionic strength, stirring rate, pH and desorption temperature and time have been studied. In optimum conditions, the repeatability for one fiber (n=5), expressed as relative standard deviation (R.S.D. %), was between 2.8% and 7.1% for the phenolic compounds. The detection limits for the studied phenolic compounds were between 0.02 and 5.8 ng mL(-1). The developed method offers the advantage of being simple to use, with shorter analysis time, lower cost of equipment, thermal stability of fiber and high relative recovery in comparison to conventional methods of analysis.

Keggin-type heteropoly compounds supported on montmorillonite clays offering strong option for efficient solid-phase microextraction coating.

Keggin-type heteropoly compounds supported on montmorillonite clays were prepared and used as a highly porous fiber coating material for solid-phase microextraction (SPME). The prepared nanomaterial was immobilized onto a stainless steel wire for fabrication of the SPME fiber. The fiber was evaluated for the extraction of some polycyclic aromatic hydrocarbons (PAHs) from aqueous sample solutions in combination with gas chromatography-mass spectrometry (GC-MS). A one at-the-time optimization strategy was applied for optimizing the important extraction parameters such as extraction temperature, extraction time, ionic strength, stirring rate, and desorption temperature and time. In optimum conditions, the repeatability for one fiber (n=3), expressed as relative standard deviation (R.S.D.%), was between 5.1% and 8.4% for the test compounds. The detection limits for the studied compounds were between 0.02 and 0.05pgmL(-1). The developed method offers the advantage of being simple to use, with shorter analysis time, lower cost of equipment, thermal stability of fiber, and high relative recovery in comparison to conventional methods of analysis.

Polythiophene/hexagonally ordered silica nanocomposite coating as a solid-phase microextraction fiber for the determination of polycyclic aromatic hydrocarbons in water.

A highly porous fiber coated with polythiophene/hexagonally ordered silica nanocomposite was prepared for solid-phase microextraction (SPME). The prepared nanomaterial was immobilized onto a stainless-steel wire for the fabrication of the SPME fiber. Polythiophene/hexagonally ordered silica nanocomposite fibers were used for the extraction of some polycyclic aromatic hydrocarbons from water samples. The extracted analytes were transferred to the injection port of a gas chromatograph using a laboratory-designed SPME device. The results obtained prove the ability of the polythiophene/hexagonally ordered silica material as a new fiber for the sampling of organic compounds from water samples. This behavior is due most probably to the increased surface area of the polythiophene/hexagonally ordered silica nanocomposite. A one-at-a-time optimization strategy was applied for optimizing the important extraction parameters such as extraction temperature, extraction time, ionic strength, stirring rate, and desorption temperature and time. Under the optimum conditions, the LOD of the proposed method is 0.1-3 pg/mL for analysis of polycyclic aromatic hydrocarbons from aqueous samples, and the calibration graphs were linear in a concentration range of 0.001-20 ng/mL (R(2) > 0.990) for most of the polycyclic aromatic hydrocarbons. The single fiber repeatability and fiber-to-fiber reproducibility were less than 8.6 and 19.1% (n = 5), respectively.

Periodic mesoporous organosilica with ionic liquid framework as a novel fiber coating for headspace solid-phase microextraction of polycyclic aromatic hydrocarbons.

Periodic mesoporous organosilica based on alkylimidazolium ionic liquid (PMO-IL) was prepared and used as a highly porous fiber coating material for solid-phase microextraction (SPME). The prepared nanomaterial was immobilized onto a stainless steel wire for fabrication of the SPME fiber. The fiber was evaluated for the extraction of some polycyclic aromatic hydrocarbons (PAHs) from aqueous sample solutions in combination with gas chromatography-mass spectrometry (GC-MS). A one at-the-time optimization strategy was applied for optimizing the important extraction parameters such as extraction temperature, extraction time, ionic strength, stirring rate, and desorption temperature and time. In optimum conditions, the repeatability for one fiber (n=3), expressed as relative standard deviation (R.S.D.%), was between 4.3% and 9.7% for the test compounds. The detection limits for the studied compounds were between 4 and 9 pg mL(-1). The developed method offers the advantage of being simple to use, with shorter analysis time, lower cost of equipment, thermal stability of fiber and high relative recovery in comparison to conventional methods of analysis.

Long-term continuous methimazole or radioiodine treatment for hyperthyroidism.

BACKGROUND: There is no general agreement as to which treatment is best for hyperthyroidism. The objective of this study is to investigate the effectiveness of continuous methimazole (MMI) treatment and to compare the results of neuropsychological testing in patients receiving long-term continuous MMI to those on replacement thyroxine following radioiodine-induced (RAI) hypothyroidism. METHODS: We enrolled 239 patients with diffuse toxic goiter who had recurrences of hyperthyroidism. Of these, 104 patients were randomized into two groups, MMI and treatment with thyroxine following RAI hypothyroidism. The remaining 135 patients voluntarily enrolled into either of the two groups. From all patients, 59 MMI-treated patients and 73 patients in the RAI group completed follow up. Thyroid function tests, serum lipids and lipoproteins, echocardiography, bone mineral density (BMD) and seven neuropsychology tests were performed at the final visit. RESULTS: In the RAI group compared to the MMI-treated group during a mean of 14 years follow up, there were more incidences of elevated TSH [> 5 mU/L; adjusted relative risk (RR) 1.23; 95% confidence interval (CI) 1.04-1.47), increased triglycerides (> 150 mg/dL; RR 2.20; 95% CI 1.34-3.62), HDL-C (< 40 mg/dL; RR 3.46; 95% CI 1.40 - 8.53), and early diastolic annular velocity (< 12.2 cm; RR 3.91; 95% CI 1.42-10.74), in addition to a decreased early diastolic to annular velocity ratio (< 6.7; RR 7.14; 95% CI 1.38-34.48). The MMI group scored better in neuropsychology tests that included mood, direction, logical memory, repeated numbers, and intelligence quotient (IQ). CONCLUSION: Long-term MMI treatment was superior to RAI therapy in patients with diffuse toxic goiter when mood, cognition, cardiac function and occurrence of thyroid dysfunction were compared. TRIAL REGISTRATION: Iranian Registry of Clinical Trials: IRCT 201009224794N1.