Co-sonicated coacervation for high-efficiency green nanoencapsulation of phytosterols by colloidal non-biotoxic solid lipid nanoparticles.

Plant sterols are used as a supplement or an additive to reduce LDL cholesterol. The poor dispersibility and instability of phytosterols are the main limitations of their application. So, we tried to overcome these problems through nanoencapsulation of them with colloidal natural RSs (SLNs) using an effective approach to achieve higher efficiency and less intrinsic coagulation. Phytosterols extracted from flax seeds oil with caffeine by a new method were encapsulated with a stable colloid of sheep fat and ostrich oil (1:2), soy lecithin, and glucose through co-sonicated coacervation. Characterization of the obtained SLNs was conducted using FTIR, UV-Vis, SEM, DLS, and GC analysis. The three-factor three-level Behnken design (BBD) was used to prioritize the factors affecting the coacervation process to optimize particle size and loading capacity of SLNs. Operational conditions were examined, revealing that the size of SLNs was below 100 nm, with a phytosterols content (EE %) of 85.46% with high positive zeta potential. The nanocapsules' anti-microbial activity and drug-release behavior were then evaluated using the CFU count method and Beer-Lambert's law, respectively. The controlled release of nanocapsules (below 20%) at ambient temperature has been tested. The stability of nano-encapsulated phytosterols was investigated for six months. All results show that this green optimal coacervation is a better way than conventional methods to produce stable SLNs for the nanoencapsulation of phytosterols.

Preparation of responsive nano-adsorbent to near-infrared laser based on tungsten disulfide for bicalutamide extraction in human biological fluids.

Bicalutamide (BLT), a non-steroidal anti-androgen, is widely used in patients with advanced prostate cancer. This study aimed to synthesize a smart modified nano-adsorbent (SMNA) based on tungsten disulfide (WS2) for solid-phase extraction of BLT from human plasma and urine samples. Briefly, we increased drug loading capacity of SMNA through the polymer grafting onto the WS2 nano-sheets. Specifically, poly (N-vinylcaprolactam) as a thermo-sensitive polymer was incorporated into the synthesized polymer networks. SMNA was characterized via TGA, XRD, FE-SEM and FT-IR techniques. The influential variables including pH (6), adsorption temperature (30°C), and contact time (10 min) were carefully optimized. After drug loading process, SMNA was exposed to 808 nm near-infrared light, the shrinkage of the thermo-sensitive polymer took place quickly and the loaded BLT released in a short time of laser irradiation. In the end, the extracted BLT was analyzed with RP-HPLC-UV system (at 270 nm wavelength). The proposed method provided favorable linearity in the range of 0.1-15 µg/mL (R2 ≥ 0.9998), the LOD and LOQ values were obtained 0.01 µg/mL and 0.04 µg/mL, respectively. The mean results of drug recovery (at the three different concentrations) of the spiked BLT in human plasma (92.08%) and urine (94.17%) were satisfactory.

Electrophoretic deposition of polyaniline nanofibers on a stainless steel wire as an adsorbent for determination of tamoxifen by SPME/GC-FID in urine samples.

Polyaniline nanofiber films were fabricated on the surface of stainless steel wire via a controllable and simple electrophoretic deposition route from a nonaqueous colloidal suspension consisting of polyaniline nanofibers. The prepared coating material was then characterized by field emission scanning electron microscopy equipped with energy dispersive spectroscopy and elemental mapping analysis. The fabricated polyaniline film-coated stainless steel wire was then utilized as an effective and novel sorbent phase for solid-phase microextraction of tamoxifen for subsequent gas chromatography/flame ionization detection of this anticancer drug. Parameters consisting of the temperature, extraction time, salt concentration, agitation speed, pH, temperature and time of desorption were studied and optimized using a one-at-a-time strategy. Under the optimum conditions, detection limit (S/N = 3), the limit of quantification (10/3 limit of detection), linear dynamic range, repeatability and reproducibility values of 0.51 µg L-1 , 1.7 µg L-1 , 2-1,130 µg L-1 , 5.7% and 8.6% were attained, respectively. The prepared fiber can preserve 90% of its efficacy after 20 consecutive cycles, demonstrating the suitable thermal stability and cyclability of the proposed solid-phase microextraction coating material for the determination of tamoxifen by gas chromatography/flame ionization detection. The route was effectively utilized to determine tamoxifen in urine samples, with relative recoveries ranging from 89 to 106%.

Near-infrared light responsive dendrimers facilitate the extraction of bicalutamide from human plasma and urine.

BACKGROUND: Today, it is well accepted that the quantitative measurement of anti-cancer drugs in human biological samples requires the development and validation of efficient bioanalytical methods. This study attempts to provide a high-capacity and thermo-sensitive nano-adsorbent for bicalutamide extraction from human biological fluids. MAIN METHODS AND MAJOR RESULTS: In this study, five generations of thermo-sensitive dendrimers were synthesized onto the surface of WS2 nano-sheets. After drug-loading process from body fluids, the near-infrared (NIR) light (at 808 nm) was applied and light-to-heat conversion by the WS2 nano-sheets led to shrinkage in polymer chains, resulting the release of the entrapped drug. Finally, the extracted drug was analyzed via HPLC-UV system (at 270 nm). The final nano-adsorbent was described via FE-SEM, XRD, FT-IR, and TGA techniques. The adsorption isotherm data were well fitted by Langmuier isotherm model (R2  = 0.9978). The mean recoveries for spiking bicalutamide at three different concentrations in plasma and urine samples were 92.12% and 94.54% under the NIR light irradiation. CONCLUSIONS AND IMPLICATIONS: We have developed a smart strategy to analyze bicalutamide in biological samples using near-infrared light irradiation in a controlled manner. All the results indicate the promising application of the proposed method for the extraction and determination of bicalutamide.

Application of adsorptive voltammetry for the detection of sub-nano molar cyclizine in biological fluids and tablets using fast Fourier transform continuous cyclic voltammetry in a flowing system.

An easy and fast Fourier transform continuous cyclic voltammetric technique (FFTCV) for monitoring of ultra trace amounts of cyclizine in a flow-injection system has been introduced in this work. The potential waveform, which was applied continuously on an Au disk microelectrode (12.5 microm in radius) consisted of the potential steps for cleaning, accumulation and potential ramp. The proposed detection method has some advantages, the greatest of which are as follows: first, it is no longer necessary to remove oxygen from the analyte solution and second, this is a very fast and appropriate technique for determination of the drug compound in a wide variety of chromatographic analysis methods. The detection limit for cyclizine was 1.8 ng ml(-1). The relative standard deviation (RSD) of the proposed technique at 5.0 x 10(-7) was 2.0 for 10 runs. The influences of pH of eluent, accumulation potential, sweep rate, and accumulation time on the determination of the cyclizine were considered. The proposed method was applied to the determination of cyclizine in a pharmaceutical preparation.