Anti-Aß-scFv-loaded polymeric nano-micelles with enhanced plasma stability.

OBJECTIVES: Immunotherapy using recombinant monoclonal antibodies specifically Anti-amyloid-beta (Anti-Aß) scFv is envisaged as an appropriate therapeutic for Alzheimer through reduction of amyloid-beta aggregation. The solubilization of therapeutics using polymeric micelles facilitates an improved bioavailability and extended blood half-life. In this study, the optimum production condition for Anti-amyloid-beta (Anti-Aß) scFv was obtained. To increase the stability of plasma, Anti-Aß-loaded polymeric micelles were synthesized. METHODS: Escherichia coli SHuffle expression strain was used and purified by Ni-NTA. Pluronics P85 and F127 micelles were used for the Anti-Aß delivery and were characterized in terms of morphology, drug loading and drug release in phosphate buffer and artificial cerebrospinal fluid. The stability profile was quantified at 4°C over a 30 days storage period. The stability in human plasma was also evaluated. KEY FINDINGS: Proteins expressed in SHuffle resulted in increased levels of protein expression and solubility. Low critical micelle concentration value and high micelle encapsulation efficiency (<200 nm) achieved via direct dissolution method. Anti-Aß-loaded micelles were around 2.2-fold more stable than Anti-Aß in plasma solution. A sustained in-vitro release of Anti-Aß from micelles was observed. CONCLUSIONS: Results confirmed that Pluronic-micelles pose benefits as a nano-carrier to increase the stability of Anti-Aß scFvin in the plasma.

Reappraisal of probiotics' safety in human.

Contrary to the safe usage of probiotics for years, their threat is still worthy of attention. Several risks have been explained or mentioned in the case reports, clinical trials and experimental studies. Due to a large number of probiotic products worldwide, the certainty of the safety of such products is a matter of concern. Current review appraises all the available information about a range of adverse effects by probiotics in different populations of consumers and almost all qualified investigations and reports, relevant to the adverse effects of probiotics. Furthermore, the effects of basic or original sources of probiotics were studied. The principally noticed adverse effects of probiotics are systemic infections, gastrointestinal side effects, skin complications, inflammation of endocardium, gene transfer from probiotics to the normal microbial flora, metabolic harmful impacts of probiotics, and immune system stimulation. The most at-risk groups consist of infants, elderly people, patients in hospitalized condition, and those with immunodeficiency due to a genetic or acquired disease. The existing evidence suggests careful evaluation of the risk-benefit ratio of probiotics prior to prescription or recommendation to use.

Development of an RP-HPLC-UV Method for Simultaneous Detection of Nimodipine and its Metabolite in Cerebrospinal Fluid of Rat.

A rapid, simple and reproducible HPLC method was developed and validated for the analysis of nimodipine (NM) and/or its metabolite, oxidized nimodipine (OX-NM) in rat cerebrospinal fluid (CSF) and artificial CSF. The NM and OX-NM were eluted in less than 10 min with no interferences from the endogenous CSF peaks. Analysis was carried out on a Eurospher Performance (RP-C18, 250 × 4.6 mm) column and UV detection at 236 nm. The mobile phase consisted of acetonitrile and water (70:30 v/v, respectively) with a flow rate of 1 mL/min. Limit of detection was 0.1 µg/mL for OX-NM. The calibration curve was linear over the concentration range of 0.5-10 µg/mL and analytical recovery was more than 95%. The coefficients of variation for intra-day and inter-day assays were less than 5%.

Nimodipine-Loaded Pluronic® Block Copolymer Micelles: Preparation, Characterization, In-vitro and In-vivo Studies.

Nimodipine (NM), as a lipophilic calcium channel blocker indicated for the prevention and treatment of neurological disorders, suffers from an extensive first pass metabolism, resulting in low oral bioavailability. Polymeric micelles, self-assembled from amphiphilic polymers, have a core-shell structure which makes them unique nano-carriers with excellent performance as drug delivery. This investigation was aimed to develop NM-loaded polymeric micelles and evaluate their potential to cross the blood brain barrier (BBB). Micelles from Pluronics®P85, F127 and F68 were fabricated for the delivery of NM, using thin film hydration and direct dissolution techniques. Critical micelle concentration of the drug-free micelles was determined by pyrene fluorescence spectroscopy. Dynamic light scattering showed that in most cases, micelles less than 100 nm and low polydispersity indices were successfully developed. Transmission electron microscopy demonstrated spherical shape of micelles. The NM-loaded micelles were also characterized for particle size, morphology, entrapment efficiency, drug loading , in vitro drug release in phosphate buffer and artificial cerebrospinal fluid (CSF). Stability was assessed from size analysis, clarity of dispersion on standing and EE(%), following 3 months storage at room temperature. The in-vitro release of NM from polymeric micelles presented the sustained-release profile. Animal studies revealed the existence of fluorescein 5-isothiocyanate-labeled micelles in rat CSF following intraperitoneal administration, proving that the micelles crossed the BBB. Anticonvulsant effect of NM was shown to be significantly greater than that of NM solution. Our results confirmed that Pluronic micelles might serve as a potential nanocarrier to improve the activity of NM in brain.

Formulation and in vitro evaluation of ciprofloxacin containing niosomes for pulmonary delivery.

In order to develop a niosome-encapsulated ciprofloxacin (CPFX) HCl formulation for pulmonary delivery, the feasibility of encapsulation of CPFX in niosomes, its stability and nebulization capability was evaluated. Various combinations of nonionic surfactants with cholesterol were used to prepare the formulations. The in vitro deposition data of the niosomal formulations were examined using an Andersen cascade impactor. Formulations composed of Span 60 and Tween 60 in combination with 40 mol% of cholesterol exhibited high encapsulation efficacy and stability and also had fine particle fraction and nebulization efficiency of about 61.9% ± 1.0 and 77.9 ± 2.8, respectively. Minimal inhibitory concentration of the niosomal CPFX against some pulmonary pathogens were lower than free CPFX. Using the MTT assay in human lung carcinoma cell line (A549), niosome-entrapped CPFX showed significantly lower cytotoxicity in comparison to the free drug. These results indicate that niosome can be used as a carrier for pulmonary delivery of CPFX via nebulization.