Aqueous Dextrose Research Articles

Facile Technology for Extemporaneous Preparation of Long-Acting Injectable Microparticulate Suspensions at the Patient Side

In this study, we present an innovative and facile in situ approach for extemporaneous preparation of sterile microparticles. An amazingly simple approach, in situ technology circumvents the stability, and scale up challenges as well as sterilization issues associated with long-acting particulate systems. Monophasic preconcentrates of donepezil base (DPZ), a model drug with a biodegradable polymer poly (DL-lactide-co-glycolide) (PLGA), with stabilizer were prepared by simple solution and sterilized by filtration (0.22 micron). The sterile preconcentrates when added to aqueous dextrose solution (total volume < 3mL) generated ready-to-inject DPZ PLGA microparticles (DPZ-PLGA-MP) with high reproducibility, entrapment efficiency (> 80%), and size ~ 80 micron. DPZ micro suspension(DPZ-MS) with high precipitation efficiency (> 90%) and size ~ 80 micron was obtained in a similar manner omitting PLGA. XRD and DSC study confirmed decreased crystallinity in the presence of PLGA. No interaction between PLGA and DPZ was evident in the FTIR study. The microparticulate dispersions exhibited good in vitro injectability when tested using the texture analyzer (force < 5 N). When evaluated using the dialysis bag method (Himedia 12-14kDa molecular weight cutoff), both microparticulate formulations exhibited controlled release up to 1week in vitro. Further, low burst release of ~ 10% at the end of 6h in the ex vivo chicken muscle study proposes great promise. Our data propose the facile extemporaneous generation of microparticles as a practical and promising approach for development of long-acting injectables. This facile approach could serve as platform technology for other drug candidates.

Specific Rotation of Aqueous Dextrose and Sucrose Under the Influence of Amino Acids Glycine and L-alanin Using LED Polarimeter

Specific Rotation of Aqueous Dextrose and Sucrose Under the Influence of Amino Acids Glycine and L-alanin Using LED Polarimeter

Investigation of the effect of temperature on aggregation behaviour and thermodynamic properties of Ornithine monohydrochloride in aqueous and aqueous dextrose and urea solutions

In this communication for the first time, we report the density ρ and speed of sound u of aqueous solution of Ornithine monohydrochloride (Ornithine·HCl) and Ornithine monohydrochloride (Ornithine·HCl) in aqueous 0.06 mol·kg−1 urea and aqueous 0.06 mol·kg−1 dextrose at T = (288.15, 293.15, 298.15, 303.15, 308.15, 313.15 and 318.15) K within the concentration range of (0.02 to 0.2) mol·kg−1. From the experimental data of density (ρ) and speed of sound (u) the various derived parameters such as apparent molar volume of solute (Vϕ) limiting apparent molar volume of solute Vϕ0, limiting apparent molar volume of transfer (ΔtrVϕ0), limiting apparent molar expansivity Eϕ0, thermal expansion coefficient (α*), second derivative of limiting apparent molar volume ∂2Vϕ0/∂T2, isentropic compressibility κs, apparent molar compression (Ks,ϕ), limiting apparent molar compression of solute KS,ϕ0, apparent molar isentropic compression of transfer ΔtrKS,ϕ0 and hydration number (nH) have been calculated.

Thermodynamic Studies of Creatinine Solvation in Aqueous Dextrose and Urea

The interactions of the drug in aqueous media are associated with many thermodynamic changes. To understand these thermodynamic changes, systematic measurements of density and speed of sound of cre...

Study of Ultrasonic Velocity Parameters of Multi-Charged Electrolytes (Potassium Ferri and Ferro Cyanide) in Aqueous Dextrose Solutions at 298.15 K

The experimental ultrasonic velocity values have been utilized to compute specific acoustic impedance ( Z), molar sound velocity ( R), molar compressibility (W), free volume ( Vf), isentropic compressibility ( Ks), internal pressure ( �i) and relative association ( RA) for the solutions of potassium ferri and ferrocyanide in aqueous dextrose solutions at 298.15 K. The results have been discussed considering all the parameters in terms of solute-solvent and solute-solute interactions and various structural effects.

Amiodarone is a cost-neutral way of preventing atrial fibrillation after surgery for lung cancer

Our aim was to estimate the costs and health benefits of routinely administered postoperative amiodarone as a prophylactic agent in reducing the risk of atrial fibrillation in patients undergoing surgery for lung cancer. This was a cost-effectiveness study, based on the randomized, controlled, double-blinded PASCART study, using avoidance of atrial fibrillation as the measure of benefit. Two hundred and fifty-four eligible, consecutively enrolled patients, undergoing surgery for lung cancer at the department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Denmark, were included and randomized to receive either 300 mg of amiodarone or placebo (5% aqueous dextrose solution), administered intravenously over 20 min immediately after surgery, followed by 600 mg of amiodarone/placebo orally twice per day (8 a.m. and 6 p.m.) for the first five postoperative days. In the amiodarone group there were 11 cases of atrial fibrillation, compared with 38 in the control group (P < 0.001). There were no differences in the length of hospital stay or resources used. The mean total costs per patient were equal and amounted to €7288 per patient (P = 0.23). There were no signs of adverse developments referable to amiodarone in this prophylactic regime. For patients undergoing surgery for lung cancer, routine use of postoperative prophylactic intravenous bolus and five subsequent days of oral amiodarone therapy reduces the risk of atrial fibrillation in a cost-neutral manner.

Multifunctional nanoplatforms for fluorescence imaging and photodynamic therapy developed by post-loading photosensitizer and fluorophore to polyacrylamide nanoparticles

We report a novel post-loading approach for constructing a multifunctional biodegradable polyacrylamide (PAA) nanoplatform for tumor-imaging (fluorescence) and photodynamic therapy (PDT). This approach provides an opportunity to post-load the imaging and therapeutic agents at desired concentrations. Among the PAA nanoparticles, a formulation containing the photosensitizer, HPPH [3-(1′-hexyloxyethyl)pyropheophorbide-a], and the cyanine dye in a ratio of 2:1 minimized the undesirable quenching of the HPPH electronic excitation energy because of energy migration within the nanoparticles and/or Förster (fluorescence) resonance energy transfer (FRET) between HPPH and cyanine dye. An excellent tumor-imaging (NIR fluorescence) and phototherapeutic efficacy of the nanoconstruct formulation is demonstrated. Under similar treatment parameters the HPPH in 1% Tween 80/5% aqueous dextrose formulation was less effective than the nanoconstruct containing HPPH and cyanine dye in a ratio of 2 to 1. This is the first example showing the use of the post-loading approach in developing a nanoconstructs for tumor-imaging and therapy. From the Clinical EditorFluorescence imaging is a rapidly evolving and relatively high-throughput tool currently only utilized in preclinical imaging. The authors of this work demonstrate a tumor-specific florescence imaging nanoplatform that enables not only imaging, but photodynamic therapy as well.

Amiodarone Cost Effectiveness in Preventing Atrial Fibrillation After Coronary Artery Bypass Graft Surgery

The purpose of this study was to estimate the costs and health benefits of routinely administered postoperative amiodarone as prevention of atrial fibrillation for patients undergoing coronary artery bypass grafting (CABG) for stable angina. This cost-effectiveness study was based on a randomized, controlled, double-blind trial (the RASCABG study) using avoidance of atrial fibrillation as the measure of benefit at the Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Skejby, Denmark. Two hundred and fifty eligible consecutively enrolled CABG patients were included to receive either 300 mg amiodarone or placebo (5% aqueous dextrose solution) administered intravenously over 20 minutes followed by 600 mg amiodarone/placebo orally twice a day (8 am and 8 pm) for the first 5 postoperative days. In the amiodarone group, there were 14 cases of atrial fibrillation compared with 32 in the control group (p < 0.01) whereas there were no differences in the length of stay. The mean total cost per patient was 7,639 euros in the amiodarone group and 7,814 euros in the placebo group (p < 0.01). Routine use of postoperative prophylactic intravenous bolus and subsequent 5 days of oral amiodarone therapy after coronary artery bypass grafting reduces the risk of atrial fibrillation and decreases the total costs of care by 175 euros per patient.

Solubilization and quantification of lycopene in aqueous media in the form of cyclodextrin binary systems

An optimized kneading method for the preparation of lycopene–cyclodextrin binary systems was developed leading to solubilization of lycopene in water and 5% (w/v) dextrose solution. Lycopene quantification in the prepared binary systems was performed by a developed spectrometric method that followed a successful single-step extraction with dichloromethane. Storage stability characteristics of the binary systems were studied at 4 °C in solution and at −20 °C in the lyophilized products. Lycopene content was monitored at λ max = 482 nm, the limit of detection was 0.41 μg/ml and relative standard deviation was less than 3.1%. The results obtained with the spectrometric method were confirmed by a HPLC method. In the presence of cyclodextrins, lycopene concentration in water was 8.0 ± 1.0, 27.1 ± 3.2 and 16.0 ± 2.2 μg/ml for β-CD, HP-β-CD and Me-β-CD, respectively. In 5% (w/v) aqueous dextrose solutions the corresponding values were 16.0 ± 1.8, 48.0 ± 5.1 and 4.0 ± 0.5 μg/ml, respectively. At 4 °C, storage stability of lycopene–cyclodextrin binary systems in water or 5% (w/v) aqueous dextrose solutions, was limited ( t 1/2 = 1–4 days). Addition of the antioxidant sodium metabisulfite increased the stability of lycopene–HP-β-CD binary system in water. At −20 °C, the lyophilized lycopene–cyclodextrin binary systems were stable for at least 2 weeks.

Conductance studies of cupric chloride in aqueous mannitol and aqueous dextrose

Limiting molar conductance of cupric chloride in aqueous mannitol and aqueous dextrose at 303, 308, 313 and 318 K have been evaluated. Results have been interpreted in terms of solute-solute and solute-solvent interactions, and structure making/structure breaking capacity of the solute from the temperature coefficient of Walden product i.e. d(Λ 0 M η)/dt. Cupric chloride has been found as structure maker in aqueous mannitol and aqueous dextrose at temperatures 303, 308, 313 and 318 K.

Quantification of 5 -HMF and dextrose in commercial aqueous dextrose solutions

5-Hydroxymethylfurfural (5-HMF) is the major thermal decomposition product formed in aqueous dextrose solutions during sterilization and upon storage. Current compendial tests employ a spectrophotometric assay for 5-HMF and a separate assay based on optical rotation for dextrose. Efforts herein focused on identification of approaches to simultaneously quantify both 5-HMF and dextrose in aqueous solutions. Initial studies employed anion exchange chromatography with pulsed amperometric detection (PAD). These studies showed that the low anion exchange column loading capacity and concentration mismatch of dextrose and 5-HMF in typical commercial solutions makes simultaneous quantitation impractical at a single sample concentration. However, mixed modes of detection for each analyte using refractive index (RI) detection for dextrose and UV detection for 5-HMF proved viable for simultaneous quantitation. The performance of both approaches was evaluated and extremely high sensitivity for 5-HMF demonstrated (30–50 ppb). The formation of 5-HMF upon the forced thermal decomposition of dextrose was monitored and compared with results from the USP spectrophotometric assay.

Contact nuclei formation in aqueous dextrose solutions

A laser Raman microprobe was used in situ to observe the growth of alpha dextrose monohydrate on alpha anhydrous dextrose crystals. The Raman spectra indicate growth of the monohydrate below 28.1°C, but the presence of only the anhydrous form above 40.5°C. Contact nucleation experiments with parent anhydrous crystals yielded only monohydrate nuclei below 28.1°C, while contacts in solutions between 34.5 and 41.0°C produced both crystalline forms, and contacts in solutions above 43.5°C produced only anhydrous nuclei. The inability of the monohydrate to grow on anhydrous crystals in the same solution that forms the two crystalline phases with a single contact precludes a simple attrition mechanism of nuclei formation. For the same reason, the hypothetical mechanism involving parent crystal stabilization of pre-crystalline clusters, allowing the clusters to grow into nuclei, is also contradicted. A third, mechanism, which may be a combination of the two, is believed to apply.

Non-equilibrium thermodynamic studies of electrokinetic effects. Part XIX. Studies with electrolyte-dextrose solutions across an inorganic ion-exchange membrane

Transport has been studied from the point of view of irreversible thermodynamics for sodium chloride, potassium chloride and lithium chloride in aqueous dextrose across a silicon dioxide plug. The phenomenological coefficients, membrane characteristics and zeta potential have been estimated for various systems. Maximum conversion efficiencies for electro-osmotic flow have been estimated. The maximum values of efficiency of energy conversion have been found to be independent of input force. The optimum values predicted by figures of merit agree with those obtained experimentally. The conditions for maximum conversion efficiency have also been discussed. All the measurements were carried out at a temperature of 303 ± 0.1 K.

Contact nucleation from aqueous dextrose solutions

AbstractContact nucleation studies were performed with the dextrose‐water system. Under some conditions two crystallographic phases were formed, which were identified in situ using a laser Raman microprobe. In addition, the growth of the contact nuclei was monitored in situ using photomicroscopy. The results are discussed in the context of contact nucleation and growth models.

Diffusivities of volatiles in concentrated solutions

Concentration profiles obtained by slicing a cylindrical gel were used to measure diffusion of volatiles in viscous aqueous dextrose solutions. The column length, slice thickness and diffusion time were optimized to maximize the repeatability of measurements, the results being very sensitive to small changes in variables. Coefficients of variation between 5 and 10% were obtained. In the presence of different concentrations of dextrose, the diffusivity of acetone decreased markedly as dextrose concentration increased. However, when the acetone concentration was varied within the range 0·6 to 13·7%, at a constant 50% (w/w) dextrose concentration, its diffusivity did not change significantly. The sliced gel system gave values of diffusivity in close agreement with those obtained by other techniques.

COMPATIBILITY OF COMMON INTRAVENOUS SOLUTIONS WITH CPD BLOOD

Blood anticoagulated with CPD was mixed with lactated Ringer's solution, 5 per cent aqueous dextrose, 5 per cent dextrose in 0.225 per cent saline, 5 per cent dextrose in 0.9 per cent saline, and 0.9 per cent saline solution in varying concentrations and incubated at room temperature and 37 C. Clots formed in the blood-lactated Ringer's mixture after five minutes at a citrate:calcium molar ratio of 4:1 or lower. Aqueous dextrose-blood mixtures showed immediate clumping with gross hemolysis after 30 minutes incubation. Blood mixed with 5 per cent dextrose and 0.225 per cent saline hemolyzed within ten minutes incubation at 37 C. No hemolysis occurred in blood mixed with 5 per cent dextrose in 0.9 per cent saline or with 0.9 per cent saline. Traces of solutions labeled with Evans blue dye remained in intravenous administration tubing even 30 minutes after a simulated transfusion was begun. Lactated Ringer's solution and 5 per cent dextrose in 0.225 per cent saline should not be administered concurrently with blood. Lactated Ringer's solution may also be harmful when used to start transfusions as it rapidly produces clots when mixed with CPD blood.

Microrheology of thickened suspensions

The viscosity of the continuous phase of Carbopol 934 (Carboxy polymethylene polymer; B. F. Goodrich Chemical Co.) suspensions has been measured by recording the diffusion coefficient of codispersed monosized polystyrene latex. The Brownian motion of the latex particles are recorded on cine films from which the mean square of the displacement for a given time interval is obtained by single frame analysis. The viscosity of the suspending media is then calculated using the Einstein equation. Measurements are also reported for water and for aqueous dextrose solutions.

Compatibility of common intravenous solutions with CPD blood.

Blood anticoagulated with CPD was mixed with lactated Ringer's solution, 5 per cent aqueous dextrose, 5 per cent dextrose in 0.225 per cent saline, 5 per cent dextrose in 0.9 per cent saline, and 0.9 per cent saline solution in varying concentrations and incubated at room temperature and 37 C. Clots formed in the blood-lactated Ringer's mixture after five minutes at a citrate:calcium molar ratio of 4:1 or lower. Aqueous dextrose-blood mixtures showed immediate clumping with gross hemolysis after 30 minutes incubation. Blood mixed with 5 per cent dextrose and 0.225 per cent saline hemolyzed within ten minutes incubation at 37 C. No hemolysis occurred in blood mixed with 5 per cent dextrose in 0.9 per cent saline or with 0.9 per cent saline. Traces of solutions labeled with Evans blue dye remained in intravenous administration tubing even 30 minutes after a simulated transfusion was begun. Lactated Ringer's solution and 5 per cent dextrose in 0.225 per cent saline should not be administered concurrently with blood. Lactated Ringer's solution may also be harmful when used to start transfusions as it rapidly produces clots when mixed with CPD blood.

Nucleation and growth kinetics for the crystallization of ice from dextrose solutions in a continuous stirred tank crystallizer with supercooled feed

AbstractThe crystallization of ice in aqueous dextrose solutions is studied in an adiabatic continuous stirred tank crystallizer with a supercooled feed stream. The effective diameter of the ice crystals was determined for various values of mean crystal residence time, feed supercooling, magma density, stirring rate, and dextrose concentration. For all process conditions the supercooling was measured at 9‐12 different locations in the crystallizer. These local supercoolings were averaged algebraically to yield the bulksupercooling.From the experimental results growth and nucleation rates have been calculated. By comparing the experimental growth rates to growth rates calculated by means of a mathematical model kinetics for the inbuilding of water molecules into the ice lattice have been determined. The growth rate appears to be directly proportional to the interface supercooling. The rate constant decreases exponentially with increasing weight percentage of dextrose in the solution.The nucleation rate was found to be directly proportional to total crystal surface per unit volume of suspension and proportional to the bulksupercooling to the power 2.1. Nucleation is believed to occur by breakage of dendrites from the surface of parent crystals.

THE ROLE OF THE APHIDS, BREVICORYNE BRASSICAE AND MYZUS PERSICAE, IN THE SPREAD OF XANTHOMONAS CAMPESTRIS, THE CAUSAL ORGANISM OF BLACK ROT OF TURNIPS

Turnip plants, heavily infested with the cabbage aphid, Brevicoryne brassicae (L.), and the green peach aphid, Myzus persicae (Sulz.), were inoculated with a virulent strain of Xanthomonas campestris (Pammel), the causal organism of black rot disease of turnips, and placed in special cages together with healthy turnip plants. Some aphids of both species were allowed to migrate naturally, and others were transferred mechanically from the diseased to the healthy plants, but no symptoms of black rot ever appeared in any of the latter plants. X. campestris was isolated from only 15% of the B. brassicae and from less than 1% of the M. persicae taken from the diseased plants. Aphids of both species were artificially contaminated externally with X. campestris by exposures to Petri plate and broth cultures of the pathogen. Internal contamination of other aphids of both species was accomplished by feeding them 0.2% aqueous dextrose solutions containing X. campestris. The pathogen was isolated from individuals m both groups of aphids thus contaminated, but none of the aphids in either group was able to infect caged, healthy turnip plants with black rot.