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Phytochemicals, such as resveratrol, curcumin, and quercetin, have many benefits for health, but most of them have a low bioavailability due to their poor water solubility and stability, quick metabolism, and clearance, which restricts the scope of their potential applications. To overcome these issues, different types of nanoparticles (NPs), especially biocompatible and biodegradable NPs, have been developed. NPs can carry phytochemicals and increase their solubility, stability, target specificity, and oral bioavailability. However, NPs are prone to irreversible aggregation, which leads to NP instability and loss of functions. To remedy this shortcoming, stabilizers like polymers and surfactants are incorporated on NPs. Stabilizers not only increase the stability of NPs, but also improve their characteristics. The current review focused on discussing the state of the art in research on synthesizing phytochemical-based NPs and their commonly employed stabilizers. Furthermore, stabilizers in these NPs were also discussed in terms of their applications, effects, and underlying mechanisms. This review aimed to provide more references for developing stabilizers and NPs for future research. [ABSTRACT FROM AUTHOR]

The aim of this study is to formulate polymeric paclitaxel nanoparticles with various stabilizers to improve solubility, enhance stability, maximize therapeutic efficacy and minimize detrimental toxicities of paclitaxel. In this study, trastuzumab-guided poly lactic-co-glycolic acid (PLGA)-loaded paclitaxel nanoparticles were formulated with pluronic F-127, polyvinyl alcohol (PVA), poloxamer 407, Tween-80, span 20, sodium dodecyl sulfate (SDS), and sodium lauryl sulfate (SLS) at different concentrations (0.5, 1, 1.5 and 2%) using the solvent evaporation method. The nanoparticles were evaluated for physicochemical characteristics and short and long-term stability. The optimum particle size (190 nm ± 12.42 to 350 nm ± 11.1), PDI (0.13 ± 0.02 to 0.2 ± 0.01), surface charge (-19.1mv ± 1.5 to −40.4mv ± 1.6), drug loading (2.43 to 9.5 %) and encapsulation efficiency (greater than 80 %) were obtained with these stabilizers while keeping the polymer concentration, temperature, probe size, amplitude and sonication time constant. The nanoformulations were stably stored at 4 °C. The nanoformulations of paclitaxel with pluronic F-127, polyvinyl alcohol (PVA), and poloxamer 407 were found to be more soluble, stable, uniform in physicochemical properties, and efficient in drug loading and encapsulation for improved therapeutic effects.

Phytochemicals, such as resveratrol, curcumin, and quercetin, have many benefits for health, but most of them have a low bioavailability due to their poor water solubility and stability, quick metabolism, and clearance, which restricts the scope of their potential applications. To overcome these issues, different types of nanoparticles (NPs), especially biocompatible and biodegradable NPs, have been developed. NPs can carry phytochemicals and increase their solubility, stability, target specificity, and oral bioavailability. However, NPs are prone to irreversible aggregation, which leads to NP instability and loss of functions. To remedy this shortcoming, stabilizers like polymers and surfactants are incorporated on NPs. Stabilizers not only increase the stability of NPs, but also improve their characteristics. The current review focused on discussing the state of the art in research on synthesizing phytochemical-based NPs and their commonly employed stabilizers. Furthermore, stabilizers in these NPs were also discussed in terms of their applications, effects, and underlying mechanisms. This review aimed to provide more references for developing stabilizers and NPs for future research.

The object of this paper is to demonstrate the performance of a Ramp-Rejecting electric Power Prefilter (RRPP), which is a modification of the Conventional electric Power Prefilter (CPP) for a speed-PSS. The RRPP can markedly reduce the undesirable swings in generator voltage and reactive power output due to ramping of turbine power. Like the Dual Input Prefilter (DIP) of the integral-of-accelerating-power (IAP) PSS the RRPP (i) significantly attenuates the torsional modes; and (ii) enhances modal damping. Significantly, the RRPP does not require an externally-estimated rotor-speed input signal - which is an important requirement of the DIP. For example, using generator terminal variables for the DIP it is difficult to accurately estimate a rotor-speed input that covers a wide range of operating conditions and modal frequencies. [ABSTRACT FROM AUTHOR]

The problem of the active stabilization of ship motions is particularly important in the case of pleasure boats or in any case of passenger ships, since the commercial value of the ship is directly related to the comfort of the load transported in this case "people", considered as stresses induced on them by the vessel movements, with particular attention to roll, given the ship geometric characteristics. Naval architects developed trough the years different solutions to reduce the roll of the ship, and consequentially to increase the passengers comfort, and the development of this solutions followed the progress of technology. Active fins have been the most used, but now the gyroscope solution is coming out with interesting solutions also for large yacht with displacement over 1000 t. The paper aimed at making a interactive comparison between the two systems: active fins and gyroscopes, trough the case study of a yacht of 77.77 m, in order to evaluate if, assuming the same capability to reduce the roll for each one of the two systems, there are other advantages or disadvantages from the point of view of the naval architecture, in particular the resistance of the hull. In fact the importance of the resistance on high Froude number hulls, like planning hulls it is well known, but the paper aimed at giving result useful for naval architects also on traditional displacement hulls, like the one considered here, in order to give also a contribution for preliminary design. The interactivity of the process has been realized using not a theoretical estimation of the gain resistance of the ship according to equations etc. but real tank tests on the hull, according to International Towing Tank Conference methodology, with and without appendages. [ABSTRACT FROM AUTHOR]

The aim of this study is to formulate polymeric paclitaxel nanoparticles with various stabilizers to improve solubility, enhance stability, maximize therapeutic efficacy and minimize detrimental toxicities of paclitaxel. In this study, trastuzumab-guided poly lactic-co-glycolic acid (PLGA)-loaded paclitaxel nanoparticles were formulated with pluronic F-127, polyvinyl alcohol (PVA), poloxamer 407, Tween-80, span 20, sodium dodecyl sulfate (SDS), and sodium lauryl sulfate (SLS) at different concentrations (0.5, 1, 1.5 and 2%) using the solvent evaporation method. The nanoparticles were evaluated for physicochemical characteristics and short and long-term stability. The optimum particle size (190 nm ± 12.42 to 350 nm ± 11.1), PDI (0.13 ± 0.02 to 0.2 ± 0.01), surface charge (-19.1mv ± 1.5 to −40.4mv ± 1.6), drug loading (2.43 to 9.5 %) and encapsulation efficiency (greater than 80 %) were obtained with these stabilizers while keeping the polymer concentration, temperature, probe size, amplitude and sonication time constant. The nanoformulations were stably stored at 4 °C. The nanoformulations of paclitaxel with pluronic F-127, polyvinyl alcohol (PVA), and poloxamer 407 were found to be more soluble, stable, uniform in physicochemical properties, and efficient in drug loading and encapsulation for improved therapeutic effects. [ABSTRACT FROM AUTHOR]

It is well recognized that protein product development is far more challenging than that for small-molecule drugs. The major challenges include inherent sensitivity to different types of stresses during the drug product manufacturing process, high rate of physical and chemical degradation during long-term storage, and enhanced aggregation and/or viscosity at high protein concentrations. In the past decade, many novel formulation concepts and technologies have been or are being developed to address these product development challenges for proteins. These concepts and technologies include use of uncommon/combination of formulation stabilizers, conjugation or fusion with potential stabilizers, site-specific mutagenesis, and preparation of nontraditional types of dosage forms-semiaqueous solutions, nonfreeze-dried solid formulations, suspensions, and other emerging concepts. No one technology appears to be mature, ideal, and/or adequate to address all the challenges. These gaps will likely remain in the foreseeable future and need significant efforts for ultimate resolution. [ABSTRACT FROM AUTHOR]

Abstract: Nanosuspensions are nanosized colloidal dispersion systems that are stabilized by surfactants and/or polymers. Because nanosizing results in the creation of new interfaces and in a positive Gibbs free energy change, nanosuspensions are thermodynamically unstable systems with a tendency toward agglomeration or crystal growth. Despite extensive research on nanosuspension technology, stability remains a limitation for pharmaceutical or industrial applications of nanosuspensions. Furthermore, the empirical relationship between stabilizer efficacy and nanosuspension stability has not been well characterized. This review focuses on the issue of nanosuspension stability in drug delivery to present the state of the art of nanosuspensions. Therefore, this review will discuss unstable suspensions, methods and guidelines for selecting and optimizing stabilizers, approaches for enhancing stability, and other factors that influence nanosuspension stability. This review could serve as a reference for the educated selection of a stabilizer for a specific drug candidate and the optimization of the operational parameters for nanosuspension formulation, rather than the currently practiced trial-and-error approach. [Copyright &y& Elsevier]

Purpose. The long-term stability of captopril in extemporaneously prepared oral liquids was studied. Methods. Captopril solutions of 1 and 5 mg/mL were prepared in sterile water for irrigation with sorbitol, disodium edetate, and sodium benzoate. The samples were stored in 100-mL amber glass bottles with a headspace of air at 22 °C for 12 months. The captopril concentration was determined by high-performance liquid chromatography at 0, 3, 6, 9, and 12 months. The pH of the solutions was also measured, and the physical appearance was recorded. The stability of the 1-mg/mL captopril preparation during 1 month of simulated use when stored at 2-8 °C was tested at the start and the end of the 12-month study period. Chemical stability was defined as retention of at least 90% of the initial captopril concentration. The microbiological quality of the preparations was tested at 0, 6, and 12 months (1 mg/mL) and 0 and 12 months (5 mg/mL). Results. Throughout the 12-month study period, the captopril concentration in the oral liquids exceeded 90% of the initial concentration. The lowest concentration (98.5%) was detected in the 5-mg/mL preparation after 3 months of storage. The 1-mg/mL preparation was stable during 1 month of simulated use, both at the start and the end of the 12-month study period. No microbiological growth was observed in any of the samples tested. Conclusion. Extemporaneously prepared oral liquid formulations of captopril 1 and 5 mg/mL were chemically stable when stored in glass bottles at room temperature for 12 months when stabilized with 0.1 mg/ mL disodium edetate at a low pH. [ABSTRACT FROM AUTHOR]

Purpose. A number of immunoglobulin intravenous (IGIV) products have been approved by the Food and Drug Administration (FDA) and are available commercially. Factors that need to be taken into consideration when selecting an appropriate IGIV product are discussed. Summary. Pathogen safety is of particular concern in IGIV products. Manufacturers of IGIV products have introduced different steps to ensure pathogen inactivation and clearance. Physical viral inactivation methods include heat and pasteurization. Chemical viral inactivation methods include acidic treatment, solvent/detergent, and caprylate. Viral removal is accomplished via precipitation, chromatography, or nanofiltration. Pathogen inactivation processes may inadvertently affect IGIV product characteristics, including composition, concentration, purity, and yield, which may, in turn, affect tolerability, efficacy, and convenience of usage. Tolerability of IGIV products is dependent on factors such as volume load, osmolarity, IgA content, and stabilizing agent. For example, sucrose, used as a stabilizing agent in some IGIV products, has been associated with an increased risk of IGIV-induced acute renal failure. The qualities of IGIV products that contribute to convenience of usage for patients and healthcare professionals include liquid formulation, longer shelf life, multiple package sizes, and shorter infusion time. Cost effectiveness of therapy is another important consideration in IGIV product selection. Contributing factors to cost effectiveness include acquisition cost, reimbursement, product preparation, storage, shelf life, and adverse event management. Conclusion. The various IGIV products differ in terms of production process, tolerability, and convenience. Pharmacists should be cognizant of these differences when ordering IGIV therapy for their patients. Additionally, overall cost-effectiveness of therapy should be an important consideration. [ABSTRACT FROM AUTHOR]

In this study, the stability of poly(butyl cyanoacrylate) (PBCA) nanoparticle suspensions was examined for up to 1 year by measuring the nanoparticle sizes. The nanoparticles were prepared with different stabilizers (dextran 70.000, poloxamer 188, or polysorbate 85), and the particle size was determined before and after purification by centrifugation and after dilution with different solutions (0.1 N HCl, 0.01 N HCl, H [sub 2]O, and PBS). The most constant sizes were with the untreated acidic nanoparticle suspensions. In all other cases, agglomeration of the particles occurred: the extent of this agglomeration and the time at which the agglomeration occurred depended on the experimental conditions. Nanoparticle polymer degradation, as indicated by size decrease, was not observed. Thus, PBCA nanoparticles can be stored as suspensions, making the lyophilization and the sometimes problematic resuspension by ultrasonication, unnecessary, which is advantageous for clinical applications. [ABSTRACT FROM AUTHOR]

The stability of invertase was studied under various conditions, including at 75°C, in presence of stabilizers (sorbitol and glycerol) at 75°C, and in the presence of denaturants (urea and trichloroacetic acid) at 37°C in reverse micelles. Stability of the invertase in reverse micelles was found to be improved over that of the enzyme in bulk aqueous solution. Sorbitol could enhance enzyme stability as it does in the bulk aqueous system. The stabilizing effect of glycerol was reduced in reverse micelles. The denaturation pattern of urea remains unaltered. However, the denaturation effect of trichloroacetic acid has been reduced in reverse micelles. [ABSTRACT FROM AUTHOR]