Development of a label-free, sensitive gold nanoparticles-poly(adenine) aptasensing platform for colorimetric determination of aflatoxin B1 in corn.

In this work, a sensitive colorimetric bioassay method based on a poly(adenine) aptamer (polyA apt) and gold nanoparticles (AuNPs) was developed for the determination of aflatoxin B1 (AFB1). The polyA apt, adsorbed on the AuNPs, especially can bind to the analyte while deterring non-specific interactions. This nano aptasensor uses cationic polymer poly(diallyl dimethyl ammonium chloride) (PDDA), as an aggregating agent, to aggregate gold nanoparticles. PolyA apt-decorated gold nanoparticles (AuNPs/polyA apt) show resistance to PDDA-induced aggregation and maintains their dispersed state (red color) with the optical absorbance signal at λ = 520 nm. However, in the presence of AFB1 in the assay solution, the specific aptamer reacts with high affinity and folds into its three-dimensional form. Aggregation of AuNPs induced by PDDA caused their optical signal shift to λ = 620 nm (blue color). AFB1 concentration in the bioassay solution determines the amount of optical signal shift. Therefore, optical density ratio in two wavelengths (A620/520) can be used as a sturdy colorimetric signal to detect the concentration of aflatoxin B1. AFB1 was linearly detected between 0.5 and 20 ng mL-1, with a detection limit of 0.09 ng mL-1 (S/N = 3). The fabricated aptasensor was applied to the detection of AFB1 in real corn samples.

Wheat germ agglutinin conjugated chitosan nanoparticles for gemcitabine delivery in MCF-7 cells; synthesis, characterisation and in vitro cytotoxicity studies.

OBJECTIVE AND AIM: Numerous clinical trials indicated combination regimens containing gemcitabine could extend progression-free survival of breast cancer patients without increasing the incidence of serious adverse effects. Orally administered gemcitabine is being metabolized by enzymes present in intestinal cells rapidly; thereupon, the current study was aimed to preparing, optimizing, and evaluating cytotoxicity of wheat germ agglutinin conjugated gemcitabine-chitosan nanoparticles (WGA-Gem-CNPs) in MCF-7 and HEK293 cells and to determining their cellular uptake by Caco-2 cells. METHODS: Gem-CNPs were prepared by Ionic Gelation method and optimum formulation was implied for WGA conjugation optimisation. Nanoparticles formation was approved by FTIR and DSC analyses; then particles were characterized by DLS and release profile was prepared. MTT assay was performed in MCF-7 and HEK293. RESULTS: Optimized Gem-CNPs and WGA-Gem-CNPs particle size were estimated as 126.6 ± 21.8 and 144.8 ± 36.1 nm, respectively. WGA conjugation efficacy was calculated as 50.98 ± 2.32 percent and encapsulation efficiency in WGA-Gem-CNPs was 69.44 ± 3.41 percent. Three-hour Caco-2 cellular uptake from Gem-CNPs and WGA-Gem-CNPs were estimated as averagely 3.5 and 4.5 folds higher than free drug, respectively. Gem-CNPs and WGA-Gem-CNPs reduced IC50 in MCF-7 cells by 2 and 2.5 folds, respectively; such decrease for HEK293 cells was as much as 2.4 and 6.3 folds, in same order. CONCLUSION: Demonstrated significant in vitro uptake of WGA-Gem-CNPs and cytotoxicity might be considered for more studies as a potential carrier for oral delivery of gemcitabine.

Preparation and characterisation of self-emulsifying drug delivery system (SEDDS) for enhancing oral bioavailability of metformin hydrochloride using hydrophobic ion pairing complexation.

AIM: The aim of this study was preparation of a self-emulsifying drug delivery system (SEEDS) containing metformin hydrochloride. METHODS: Hydrophobic ion paired complexes were prepared by electrostatic interaction between metformin and sodium lauryl sulphate (SLS). The nanodroplets were optimised using two-level full factorial methodology and their morphology were examined. In vitro release of metformin from SEDDS was evaluated in simulated gastric and intestinal fluids. Finally, the ex-vivo efficacy of the optimised formulation in enhancing the intestinal permeability of metformin was evaluated using non-everted intestinal sac. RESULTS: The data revealed that in weight ratio 1:4(metformin: SLS), the highest recovery was achieved. The physico-chemical properties of the optimised nano-droplets including size, polydispersity index (PdI), zeta potential, and loading efficiency (%) were 192.33 ± 9.9 nm, 0.275 ± 0.051; -1.52 mV, and 93.75 ± 0.77% (w/w), respectively. CONCLUSIONS: The data obtained from the intestinal transport study demonstrated that SEDDS can significantly enhance the oral permeability of the compound.

Assessing the Risk of Nephrotoxicity Associated with Aminoglycosides in Brucellosis Patients: A Cross-sectional Study.

OBJECTIVE: The purpose of this study was to investigate renal function in patients with brucellosis before and at the end of gentamicin therapy. To ensure the safety of therapeutic doses of gentamicin, renal functions in brucellosis patients were monitored regarding drug serum levels and check for early detection biomarkers of nephrotoxicity. METHODS: In this cross-sectional study, 41 patients (25 men and 16 women, aged over 15 years) were included, with confirmed acute brucellosis that referred to Brucellosis Research Center in Hamadan, west of Iran between March 2018 to February 2019. At baseline before treatment (first step) and 7 days after gentamicin administration (second step), serum uric acid, blood urea nitrogen (BUN), serum and urine creatinine, erythrocyte sedimentation rate (ESR), quantitative C-reactive protein (CRP) and urinary ß2-microglobulin (ß2M) were measured. Gentamycin serum level due to the highest risk of nephrotoxicity with this drug in aminoglycoside class was also checked by HPLC method. The data were analyzed using SPSS version 22. RESULTS: The mean urinary ß 2M level, serum and urinary creatinine, uric acid, BUN, and quantitative CRP levels in the first step and second step, there were no statistical differences between the two steps. There was a correlation between urinary creatinine and ESR. In addition, a positive correlation was found between urinary ß2M and serum gentamicin level. ESR levels have been significantly reduced in the patients after the treatment compared to before it. CONCLUSION: Our findings confirm that gentamicin is safe at the dose of 5 mg/kg/day for one week intravenously in brucellosis patients.

Design and Fabrication of a Gas Sensor Based on a Polypyrrole/Silver Nanoparticle Film for the Detection of Ammonia in Exhaled Breath of COVID-19 Patients Suffering from Acute Kidney Injury.

One of the serious complications of COVID-19 is acute kidney injury (AKI), leading to a decrease in kidney function and even death. The concentration of ammonia (NH3) in the exhaled breath (EB) of COVID-19 patients suffering from AKI symptoms will be significantly increased. In this work, the detection of breath NH3 was performed at gold interdigital electrodes modified with a soluble polypyrrole microparticle and silver nanoparticle film (Au-IDEs/S-PPyMPs/AgNPs) as a noninvasive chemiresistor gas sensor. The response behavior of unmodified and modified gas sensors toward NH3 and other interfering compounds was studied. The Au-IDEs/S-PPyMPs/AgNPs exhibited NH3 detection in the linear dynamic range of 1.00-19.23 ppm, with a limit of detection of 0.12 ppm. Finally, the fabricated gas sensor was used to monitor the NH3 concentration in the EB of COVID-19 patients suffering from AKI symptoms. For this purpose, the gas sensor was validated in 19 EB samples (seven COVID-19-positive patients, four COVID-19-negative patients, and eight post-COVID-19 patients). The gas sensor was directly exposed to the EB samples, followed by recording the changes in electrical resistance via a low-cost digital multimeter. The sensing mechanism was explained as the interaction between breath NH3 and sensing materials. The breath NH3 concentrations have a desirable correlation (R2 = 0.8463) with the estimated glomerular filtration rate (eGFR) values in COVID-19-positive patients. The fabricated gas sensor can distinguish COVID-19-positive patients suffering from AKI symptoms from COVID-19-negative patients and post-COVID-19 patients. The present work can pave the way for the development of a simple and efficient analytical approach for COVID-19 patients with AKI without the need for sample pretreatment.

A novel label-free colorimetric polyA aptasensing approach based on cationic polymer and silver nanoparticles for detection of tobramycin in milk.

In this study, a novel colorimetric bioassay method was developed for the sensitive determination of tobramycin (TOB). To detect TOB, silver nanoparticles (AgNPs) were decorated with TOB-specific aptamers (apt), and positively charged poly diallyl dimethyl ammonium chloride (PDDA) was used. As long as tobramycin is not present in the assay system, PDDA can coalesce with the aptamer, and AgNPs would remain stable (λmax = 400 nm) in the dispersed system against PDDA-induced aggregation. When TOB is added, aptamer can bind to the compound, which leads to release of PDDA and subsequent aggregation of AgNPs (λmax = 540 nm). This remarkable change, as a colorimetric analytics signal, can be used for quantitative analysis of TOB. TOB can be detected by this highly sensitive colorimetric aptasensor with a limit of detection (LOD) of 70 pM. Furthermore, TOB can be detected with the naked eye at concentrations above 1 nM.

Nano optical and electrochemical sensors and biosensors for detection of narrow therapeutic index drugs.

For the first time, a comprehensive review is presented on the quantitative determination of narrow therapeutic index drugs (NTIDs) by nano optical and electrochemical sensors and biosensors. NTIDs have a narrow index between their effective doses and those at which they produce adverse toxic effects. Therefore, accurate determination of these drugs is very important for clinicians to provide a clear judgment about drug therapy for patients. Routine analytical techniques have limitations such as being expensive, laborious, and time-consuming, and need a skilled user and therefore  the nano/(bio)sensing technology leads to high interest.

Enhancement of in vitro antitumour activity of epirubicin in HER2+ breast cancer cells using immunoliposome formulation.

Epirubicin (EPI) is one of the potent breast cancer (BC) chemotherapeutic agents, but its adverse effects limit its efficacy. Herein, EPI was selected to be loaded in liposomal carrier, which has been targeted by a monoclonal antibody, Herceptin. The preparation process of liposomes was a modified ethanol injection method followed by Herceptin conjugation. The in vitro cell toxicity and cellular uptake of optimum formulation against HER2+ and HER2- cancer cell lines were evaluated. The results showed that the drug loading (DL%) and encapsulation efficiency (EE%) of liposome preparation method yielded 30.62% ± 0.49% and 62.39% ± 8.75%, respectively. The average size of naked liposomes (EPI-Lipo) and immunoliposomes (EPI-Lipo-mAb) was 234 ± 9.86 and 257.26 ± 6.25 nm, with a relatively monodisperse distribution, which was confirmed by SEM micrographs. The release kinetic followed Higuchi model for both naked and immunoliposomes. In vitro cytotoxicity study on three different BC cell lines including BT-20, MDA-MB-453 and MCF-7 demonstrated higher toxicity of EPI in the Herceptin conjugated form (EPI-Lipo-mAb) in comparison with the free EPI and EPI-Lipo in HER2 overexpressing cell line. In addition, the cellular uptake study showed a higher uptake of immunoliposomes by MCF-7 cells in comparison with naked liposomes. In conclusion, these data show that the targeted delivery of EPI to breast cancer cells can be achieved by EPI-Lipo-mAb in vitro, and this strategy could be used for breast cancer therapy with further studies.

Targeting Solid Lipid Nanoparticles with Anisamide for Docetaxel Delivery to Prostate Cancer: Preparation, Optimization, and In-vitro Evaluation.

The purpose of the current study was to prepare and characterize the targeted solid lipid nanoparticles (SLNs) containing docetaxel (DTX) for prostate cancer treatment. The goal has been achieved by locating anisamide (Anis) ligand on the surface of SLNs, which can interact with the overexpressed sigma receptor on the prostate cancer cells. DTX loaded SLNs were prepared by high shear homogenization and ultra-sonication method and optimized by applying experimental design. The average particle size and the entrapment efficiency of the optimum DTX-SLN were 174 ± 9.1 nm and 83 ± 3.34%, respectively. The results of differential scanning calorimetry showed that DTX had been dispersed as amorphous in the nanocarriers. Scanning electron microscopy (SEM) images confirmed the nanoscale size and spherical shape of the nanoparticles. The cytotoxicity studies have demonstrated that IC50 of free drug, DTX-SLN and DTX-SLN-Anis was 0.25 ± 0.01, 0.23 ± 0.02, 0.12 ± 0.01 nM on PC3 cell line and 20.9 ± 3.89, 18.74 ± 7.43, and 14.68 ± 5.70 nM on HEK293 cell line, respectively. Targeted DTX-SLN-Anis was acted more effectively on prostate cancer cells in comparison to DTX-SLN and free drug. The results of this study have depicted that the anti-cancer drug loaded in targeted SLNs can be a promising way for cancer treatment. In addition, performing in-vivo studies will be complementary to these findings.

Preparation, characterization, and in vivo evaluation of perphenazine-loaded nanostructured lipid carriers for oral bioavailability improvement.

OBJECTIVE: The main scope of the present investigation was to improve the bioavailability of perphenazine (PPZ) by incorporating it into the nanostructured lipid carriers (NLCs). SIGNIFICANCE: As a result of lipophilic nature and poor aqueous solubility, as well as extensive hepatic metabolism, PPZ has low systemic bioavailability via the oral route. NLCs have shown potentials to surmount the oral delivery drawbacks of poorly water-soluble drugs. METHODS: The PPZ-NLCs were prepared by the emulsification-solvent evaporation method and subjected for particle size, zeta potential, and entrapment efficiency (EE) analysis. The optimized NLCs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and powder X-ray diffractometry (PXRD). Besides, in vitro release behavior, storage stability, and pharmacokinetic studies followed by a single-dose oral administration in rats were performed. RESULTS: Optimized PPZ-NLCs showed a particle size of less than 180 nm with appropriate EE of more than 95%. Microscopic images captured with SEM and TEM exhibited that NLCs were approximately spherical in shape. DSC and PXRD analysis confirmed reduced crystallinity of PPZ after incorporation in NLCs. FTIR spectra demonstrated no chemical interactions between PPZ and NLC components. In vitro release studies confirmed the extended-release properties of NLC formulations. PPZ-NLCs exhibited good stability at 4 °C within three months. The oral bioavailability of NLC-6 and NLC-12 was enhanced about 3.12- and 2.49-fold, respectively, compared to the plain drug suspension. CONCLUSION: NLC can be designated as an effective nanocarrier for oral delivery of PPZ.

Hydrophobic ion pairing with cationic derivatives of α-, ß-, and γ-cyclodextrin as a novel approach for development of a self-nano-emulsifying drug delivery system (SNEDDS) for oral delivery of heparin.

To enhance the oral bioavailability of heparin, a self-nano-emulsifying drug delivery system (SNEDDS) was developed using hydrophobic ion-pairing with cationic polymers of α-, ß-, and γ-cyclodextrins (CPCDs). Hydrophobic ion paired complexes were formed, and the recovery of heparin was determined in n-hexane and isopropyl myristate (IPM). The SNEDDSs were prepared and were optimized using D-optimal response surface methodology (RSM). The determination of the recovery of complexes in IPM revealed that in cationic α-cyclodextrin, the highest recovery was achieved at the heparin: CPCD weight ratio of 1:0.5. However, in cationic ß-cyclodextrin the highest recovery was obtained at the weight ratio of 1:4. Similar to CPßCD, for ealed that in c the highest recovery was obtained at 1:4 weight ratio. The size of optimized nano-droplets was found to be 127.00 ± 4.1, 184.00 ± 6.43, and 216.00 ± 5.43 nm; polydispersity index (PdI) values were reported as 0.372 ± 0.005, 0.163 ± 0.008, 0.236 ± 0.003; and calculated loading efficiency (LE%) were 84.60 ± 3.62, 91.06 ± 2.49, and 92.81 ± 0.70% for SNEDDS preparations incorporating cationic derivatives of α-, ß-, and γ-cyclodextrin, respectively. The in vitro release study revealed that SNEDDS preparations containing cationic γ-cyclodextrin posed the slowest release rate. Data achieved from cellular uptake study showed that the SNEDDS containing α-cyclodextrin had the highest cumulative uptake percentage after 6 h post-exposure; same results were obtained in the intestinal transport study demonstrating SNEDDS containing α-cyclodextrin posed the highest transport efficiency with Papp of 24.85 × 10-r ± 1.06 × 10-± cm.s-m.

Pharmacokinetics and brain distribution studies of perphenazine-loaded solid lipid nanoparticles.

BACKGROUND: Perphenazine (PPZ) is a typical antipsychotic that is mainly administrated for the treatment of schizophrenia. Due to its highly lipophilic nature and extensive hepatic first-pass metabolism, its oral bioavailability is low (40%). OBJECTIVE: The novel nanocarriers like solid lipid nanoparticles (SLN) have been reported to be highly effective for improving the therapeutic effect of drugs. Therefore the main scope of the present investigation was the evaluation of in vivo characteristics of PPZ-SLN in terms of pharmacokinetic parameters and brain distribution. METHODS: The PPZ-SLN was prepared by the solvent-emulsification and evaporation method. The storage stability of PPZ-SLN and empty SLN powders was studied for 3 months. In vivo pharmacokinetic studies and brain distribution evaluations were performed following a single oral dose administration of PPZ and PPZ-SLN suspensions on male Wistar rats. An HPLC method was established and validated for the quantitative determination of PPZ in plasma and brain samples. RESULTS: The storage stability studies revealed the good storage stability of the both PPZ-SLN and empty SLN at 4 °C. Compared to PPZ suspension, the relative bioavailability and the brain distribution of PPZ-SLN were increased up to 2-fold and 16-fold, respectively. Mean residence time (MRT) and half-life (t1/2) of PPZ-SLN were significantly (p value < 0.01) increased in both plasma and brain homogenate compared to PPZ suspension. CONCLUSION: The significant improvement in the pharmacokinetic properties of PPZ following one oral dose indicates that SLN is a promising drug delivery system for PPZ and shows a high potential for successful brain delivery of this antipsychotic.

Oral delivery of indinavir using mPEG-PCL nanoparticles: preparation, optimization, cellular uptake, transport and pharmacokinetic evaluation.

Introduction: Indinavir (IDV) is a potent HIV protease inhibitor used in the treatment of human immunodeficiency virus (HIV). IDV is a weak base with limited aqueous solubility in its unprotonated form; therefore, solubility of IDV in the gastrointestinal tract fluids is the rate-limiting step of its absorption and onset of action. However, in many cases, drugs are not absorbed well in the gastrointestinal tract; polymer nanoparticles were recognized as an effective carrier system for drug encapsulation and are now studied as a vehicle for oral delivery of insoluble compounds. Preparation of methoxy poly (ethylene glycol)-poly (e-caprolactone) (mPEG-PCL) nanoparticles is among the strategies to overcome low bioavailability of drugs with poor aqueous solubility. Materials and method: The structure of the copolymers was characterized using 1H NMR, FTIR, DSC and GPC techniques. IDV loaded mPEG- PCL nanoparticles prepared by emulsification solvent evaporation method were optimized using D-optimal experimental design and were characterized by various techniques such as DLS, DSC, XRD, AFM and SEM. Using Caco-2 cells as a cellular model, we studied the cellular uptake and transport. Results: In vivo pharmacokinetic studies were performed in rats. The plasma AUC (0-t), t1/2 and Cmax of IDV-mPEG-PCL NPs were increased by 5.30, 5.57 and 1.37 fold compared to the IDV solution, respectively. Conclusion: The results of this study are promising for the use of biodegradable polymeric nanoparticles to improve oral drug delivery.

ß-lactoglobulin-irinotecan inclusion complex as a new targeted nanocarrier for colorectal cancer cells.

Beta-lactoglobulin (ß-LG) is a lipocalin family member whose general function appears to be solubilizing and transport of hydrophobic molecules. Some properties such as avalability, ease of purification, and peculiar resistance to acidic environments can make ß-LG as a carrier for hydrophobic and acid labile drugs for oral administration. In this protein vehicle, drug could be protected in acidic environment of stomach and then released within the basic small intestine. In this study, the potential of ß-LG as a nanocarrier for oral delivery of a potent agent in colorectal cancer treatment, irinotecan, was evaluated. The nanoparticle was prepared by the physical inclusion complex method. Size, drug loading, encapsulation efficiency, and in vitro drug release at various pH values were investigated. The optimum formulation showed a narrow size distribution with an average diameter of 139.86 ± 13.75 nm and drug loading about 84.33 ± 5.03%. Based on the results obtained from docking simulation of irinotecan-complex, there are two distinct binding sites in this nanocarrier. Cytotoxicity of this nanocarrier on the HT-29 cancer cell line and AGS was measured by MTT assay. The cytotoxicity experiment showed that the drug-loaded nanocarrier was more effective than free drug. The higher release percent of drug from the ß-LG complex at pH 7.4 compared to pH 1.2 indicated that the proposed nanocarrier could be introduced as a suitable nanovehicle for labile drugs in acidic medium targeted for colorectal segment.

A Comprehensive Physicochemical, In Vitro and Molecular Characterization of Letrozole Incorporated Chitosan-Lipid Nanocomplex.

PURPOSE: The aim of this study is to show a new mesomicroscopic insight into Letrozole (LTZ) loaded nanocomplexes and their ex vivo characteristics as a drug delivery system. METHODS: The LTZ loaded hybrid chitosan-based carrier was fabricated using a modified ionic crosslinking technique and characterized in more detail. To understand the mechanism of LTZ action encapsulated in the hybrid polymer-lipid carrier, all-atom molecular dynamics simulations were also used. RESULTS: The physicochemical properties of the carrier demonstrated the uniform morphology, but different drug loading ratios. In vitro cytotoxic activity of the optimized carrier demonstrated IC50 of 67.85 ± 0.55 nM against breast cancer cell line. The ex vivo study showed the positive effect of nanocomplex on LTZ permeability 7-10 fold greater than the free drug. The molecular dynamic study also confirmed the prsence of hydrophobic peak of lipids at a distance of 5 Å from the center of mass of LTZ which proved drug entrapment in the core of nanocomplex. CONCLUSIONS: The hybrid nanoparticle increased the cytotoxicity and tissue permeability of LTZ for oral delivery. This study also confirmed the atomic mesostructures and interaction of LTZ in the core of hybrid polymer-lipid nanoparticles.

Folate Conjugated Hybrid Nanocarrier for Targeted Letrozole Delivery in Breast Cancer Treatment.

PURPOSE: Letrozole as a steroidal anticancer drug with hydrophobic nature is usually administrated by oral route for patient treatment and the injectable formulation for this drug has not still been reported. In this study, a new letrozole incorporated folate-conjugated polymer - lipid hybrid nanoparticles - is introduced for cancer treatment. METHODS: Nanoparticles were fabricated via modified oil in water ionic gelation method using optimization parameters and then were coupled to folic acid using carbodiimide activation. The physicochemical characterization in vitro drug release, cytotoxicity, and then ex vivo study of obtained carrier was investigated. RESULTS: Both thermal and crystallography studies proved the amorphous loading of drug in the nanocarrier. The cytotoxicity investigation with an average IC50 value of 79 ± 2.40 nM proved the efficiency of the coupled folic acid carrier for the intracellular uptake of letrozole on the breast cancer line. Ex vivo, the study proved the positive effect of the letrozole entrapment on the drug bioavailability. CONCLUSIONS: The obtained targeted nanocarrier could overcome the limitations associated with the LTZ as a potent non-steroidal drug. Both the entrapment and therapeutic efficiency of letrozole in the amphiphilic carrier were increased using the lipid nanoparticles and the surface modification, respectively.

Pharmacokinetic study of furosemide incorporated PLGA microspheres after oral administration to rat.

OBJECTIVES: The purpose of the current study was to assess the feasibility of microspheres from biocompatible polymer for oral bioavailability (BA) enhancement of potent sulfonamide- type loop diuretic- Furosemide - which used in the treatment of congestive heart failure, caused edema, cirrhosis, renal disease and as an adjunct in acute pulmonary edema. The comparatively poor and inconstant BA of furosemide, which occurs site-specifically in the stomach and upper small intestine, has been ascribed to the poor dissolution of furosemide. MATERIALS AND METHODS: In attempt to enhance the drug BA, poly (dl-lactic-co-glycolic acid) (PLGA) microspheres of furosemide were obtained using solvent-evaporation method and the carrier characteristics were investigated subsequently. RESULTS: The in vivo performance of optimum formulation was assessed by pharmacokinetic evaluation of drug after orally administration of free and loaded in microspheres to rats (4 mg/Kg). For this reason, the concentration of drug in plasma was measured by a new developed and sensitive method of HPLC. Acceptable drug loading and encapsulation efficiency of microspheres were obtained to be 70.43 and 85.21 %, respectively. Microspheres provided improved pharmacokinetic parameters (Cmax = 147.94 ng/ml, Tmax = 1.92 hr) in rats as compared with pure drug (Cmax = 75.69 ng/ml, Tmax = 1.5 hr). The obtained AUC of drug in microsphere was 10 fold higher than of the free drug. CONCLUSION: The results showed that the prepared microspheres successfully improved BA of the poorly water-soluble drug effectively.

The Role of Nanoparticle in Brain Permeability: An in-vitro BBB Model.

Membrane permeability and P-glycoprotein (P-gp) efflux system are regulating factors in the drug brain penetration. Recently, some drug delivery systems have been developed to overcome these limitations. In this study, Metoclopramid has been encapsulated in PLGA nanoparticles using the emulsification/solvent evaporation technique for in-viro evaluation of the effect of PLGA nanoparticles on BBB permeability. Subsequently, prepared nanoparticles were characterized using PCS, TEM, FT-IR, DSC and XRD techniques and in-viro cell permeability of optimum formulation was evaluated using MDCK cell line as BBB model. Data investigation showed that prepared nanoparticles have the entrapment efficiency of 50 %. PCS investigation showed that prepared nanoparticles have an average size of approximately 150 ± 14 nm and a relatively monodisperse distribution. TEM micrographs of the samples showed spherical shape and smooth surface with a particle size of nanometric range. Through DSC thermograms and XRD diffractograms analysis, it was demonstrated that there was no crystalline form of the drug in the loaded formulation. Moreover, our results showed that the greater crossing of metoclopramide in the form of nanoparticle in comparison with the free form. The widely used rhodamine-123 transport assay performed in the MDCK cells demonstrated the presence of P-glycoprotein in this model.

Safety and efficacy of Intraurethral Mitomycin C Hydrogel for prevention of post-traumatic anterior urethral stricture recurrence after internal urethrotomy.

BACKGROUND: Evaluation of the safety and efficacy of intraurethral Mitomycin C (MMC) hydrogel for prevention of post-traumatic anterior urethral stricture recurrence after internal urethrotomy. METHODS: A thermoresponsive hydrogel base consisting of 0.8 mg MMC with 1cc water and propylene glycol to PF-127 poloxamer was used in theater. 40 male patients with short, non-obliterated, urethral stricture were randomized into 2 groups: control and MMC. After internal urethrotomy, the MMC group patients received the MMC-Hydrogel while the others were just catheterized. Both groups had their catheters for at least 1 week. After surgery, they were followed up by means of medical history and physical examination, monitoring voiding patterns and retrograde urethrogram at 1 month, 6 months and 1 year after surgery. RESULTS: 40 male patients between 14 to 89 years old (Mean = 54.15) underwent internal urethrotomy. The average age for the control and MMC group was 54.55±21.25 and 53.75±24.75 respectively. In a comparison of age between the two groups, they were matched (P=0.574). Stricture length was 10.7±5.9 and 9.55±4.15 mm for the control and MMC group respectively. There were no statistically meaningful differences between the two groups (P=0.485). Fifteen patients had a history of one previous internal urethrotomy which in a comparison between the two groups meant there was no meaningful difference (P=0.327). During postoperative follow up, total urethral stricture recurrence happened in 12 patients: 10 patients (50%) in control group and 2 patients (10%) in MMC group. The difference was statistically significant (P=0.001). There were no significant complications associated with the MMC injection in our patients. CONCLUSIONS: Based on our results, MMC Hydrogel may have an anti-fibrotic action preventing post-traumatic anterior urethral stricture recurrence with no side effects on pre-urethral tissue. Due to our study limitations, our follow up time and the small number of patients, our results were not conclusive and further studies will be needed with a longer follow up time.

Clinical Features and Drug Characteristics of Patients with Generalized Fixed Drug Eruption in the West of Iran (2005-2014).

Background. Generalized fixed drug eruption is a specific variant of fixed drug eruption with multifocal lesions. Diagnosis of this drug reaction is straightforward, but occasionally recognition of the causative drug is not possible. This study was aimed at evaluating the clinical features and culprit drugs in generalized fixed drug eruptions in the west of Iran. Method. This cross-sectional study was carried out on 30 patients with criteria of generalized fixed drug eruption over 9 years. Demographic, clinical, and drug intake information were collected. Results. Out of 30 patients (17 females and 13 males) with the mean age of 26.67 ± 10.21 years, 28 (93.3%) and 2 (6.7%) cases had plaque and bullous clinical presentation, respectively. Upper limbs were the most common (90%) site of involvement. The antibiotic group, especially cotrimoxazole (26.1%), was reported to be the most common offending drug, but the causative drug was not determined in 7 (23.3%) patients. Conclusion. Many cases of generalized fixed drug eruption firstly presented as limited lesions and led to generalized lesion due to repeated intake of the causative drug. No causative drug was found in some patients, which might be associated with concurrent intake of several drugs, multiple FDE, and peculiarity of the patch test.