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PubMedDate not supplied

Adsorption of recombinant human granulocyte colony stimulating factor (rhG-CSF) to polyvinyl chloride, polypropylene, and glass: effect of solvent additives.

The adsorption of recombinant-derived proteins to glass and polymeric materials used in their packaging and delivery remains a problem. Loss of these very expensive proteins to surface adsorption not only results in reduced yields during purification and scale-up, but also to decreased therapeutic efficacy. The purpose of the present investigation was to inhibit/minimize adsorption of a model protein, namely, recombinant human granulocyte colony stimulating factor (rhG-CSF) to glass, polyvinyl chloride (PVC), and polypropylene by inclusion of select solvent additives. Solvent additives used to inhibit/minimize surface adsorption included glycerin, U.S.P. (0.5%, 1%, 5%, and 25% v/v), Pluronic F-127 (0.005%, 0.05%, and 0.5% w/w), Pluronic F-68 (0.005%, 0.05%, and 0.5% w/w), Tween 80 (0.005% and 0.05% w/w) and Tween 20 (0.005%, 0.05%, and 0.5% w/w). Over the rhG-CSF concentration range of 0.0 ng/ml to 300 ng/ml, the amount of rhG-CSF bound per cm2 of PVC increased with an increase in the rhG-CSF concentration tested. At rhG-CSF equilibrium concentrations of 262 +/- 3.7 ng/ml and 136 +/- 1.9 ng/ml, the rhG-CSF bound/cm2 of PVC at 22 degrees C and 45 degrees C reached a maximum of 37.6 +/- 9.8 ng/cm2 and 165.2 +/- 11.7 ng/cm2, respectively. The adsorption isotherms determined at each temperature were described by the classic Freundlich equation. Moreover, the rate of adsorption of rhG-CSF to PVC was extremely rapid. The mean values of the percent of rhG-CSF bound to PVC after only 10 minutes of equilibration at 22 degrees C and 45 degrees C were 92.8 +/- 9.2 percent and 97.3 +/- 17.9 percent, respectively. The mean values of the percent of rhG-CSF bound to PVC at 22 degrees C and 45 degrees C after 24 hours were 52.4 +/- 10.9% and 70.0 +/- 9.7%, respectively, indicating that some desorption of rhG-CSF does occur during 24 hr. However, surface adsorption of rhG-CSF to PVC was shown to be irreversible over a 1 hr time period. Using viscometry, an estimate of the thickness of the adsorbed layer of rhG-CSF to glass was determined to be approximately 1 micron. The overall rank order of the solvent additives for minimizing adsorption of rhG-CSF to PVC was Tween 20 > Tween 80 > Pluronic F-127 > Pluronic F-68. Tween 20 was the most effective solvent additive for inhibiting surface adsorption of rhG-CSF to parenteral vials made of either glass or polypropylene.

Adsorption↗
PubMed2006

Safety and reliability analysis in a polyvinyl chloride batch process using dynamic simulator-case study: Loss of containment incident.

In this paper, a novel methodology in batch plant safety and reliability analysis is proposed using a dynamic simulator. A batch process involving several safety objects (e.g. sensors, controller, valves, etc.) is activated during the operational stage. The performance of the safety objects is evaluated by the dynamic simulation and a fault propagation model is generated. By using the fault propagation model, an improved fault tree analysis (FTA) method using switching signal mode (SSM) is developed for estimating the probability of failures. The timely dependent failures can be considered as unavailability of safety objects that can cause the accidents in a plant. Finally, the rank of safety object is formulated as performance index (PI) and can be estimated using the importance measures. PI shows the prioritization of safety objects that should be investigated for safety improvement program in the plants. The output of this method can be used for optimal policy in safety object improvement and maintenance. The dynamic simulator was constructed using Visual Modeler (VM, the plant simulator, developed by Omega Simulation Corp., Japan). A case study is focused on the loss of containment (LOC) incident at polyvinyl chloride (PVC) batch process which is consumed the hazardous material, vinyl chloride monomer (VCM).

Computer Simulation↗
PubMed2006

Effects of polyvinyl chloride overwrap film, high-oxygen modified atmosphere packaging, or ultra-low-oxygen modified atmosphere packaging on bone marrow discoloration in beef humerus, rib, thoracic vertebra, and scapula.

Meat retailers have reported bone marrow discoloration to be a problem, especially in modified atmosphere packages (MAP). Therefore, it is important to determine the prevalence and cause(s) of bone marrow discoloration in different beef bones and packaging systems. Thirty-six beef humeri, ribs, scapulas, and thoracic vertebrae from USDA Select and Choice carcasses were obtained from a commercial abattoir, cut into 2.54-cm-thick sections at 4 d postmortem, and packaged into 1 of 3 systems: 1) polyvinyl chloride film (PVC) overwrap; 2) high-oxygen (80% O2, 20% CO2) MAP; and 3) ultra-low-oxygen (70% N2, 30% CO2) MAP. Instrumental reflectance and visual color scores were taken on d 0, 2, and 4, and on d 0 to 4 of display, respectively. Bone marrow was extracted from humeri, ribs, and thoracic vertebrae for analysis but not from scapulas. Ribs, scapulas, and thoracic vertebrae packaged in PVC and high-oxygen MAP developed undesirable gray or black discoloration. In ultra-low-oxygen MAP, mean visual color scores were acceptable throughout the entire display period. Discoloration (darkening) was more extensive for ribs, scapulas, and thoracic vertebrae than for humeri, especially for bones packaged in PVC and high-oxygen MAP. Humeri had lower (P < 0.05) a* values (larger positive a* values indicate a redder color) than the other bones. The a* values for ribs, scapulas, and thoracic vertebrae decreased (P < 0.05) over time. Chroma showed that bone marrow discolored during display, but graying was dramatically less for all bones packaged in ultra-low-oxygen MAP and for humeri in PVC and high-oxygen MAP. Humeri marrow had lower (P < 0.05) 2-thiobarbituric acid reactive substances (TBARS) than did ribs and thoracic vertebrae marrow. Ultra-low-oxygen MAP resulted in the least amount of change in TBARS from d 0 to 4, whereas thoracic vertebrae marrow had greater (P < 0.05) TBARS values at d 4 of display than at d 0 in PVC and high-oxygen MAP. Humeri marrow had dramatically less total Fe and hemoglobin than did that of ribs and thoracic vertebrae for all packaging systems. Myoglobin was undetectable in humeri marrow. The much larger amounts of Fe and hemoglobin in ribs and thoracic vertebrae likely contribute to marrow discoloration. Bone marrow discoloration was distinct in ribs, scapulas, and thoracic vertebrae packaged in PVC or high-oxygen MAP. Bones packaged in ultra-low-oxygen MAP had minimal discoloration.

Animals↗
PubMed1997

Rapid loss of fentanyl citrate admixed with fluorouracil in polyvinyl chloride containers.

OBJECTIVE: To study the physical compatibility and chemical stability of fluorouracil 1 and 16 mg/mL with fentanyl citrate 12.5 micrograms/mL in dextrose 5% and in sodium chloride 0.9% injection. DESIGN: Test solutions of the drugs in dextrose 5% injection and in sodium chloride 0.9% injection were prepared in triplicate and stored at -20, 4, 23, and 32 degrees C. Samples were removed immediately and at various times over 7 days and stored at -70 degrees C until analyzed. Physical compatibility was assessed visually and by measuring turbidity with a color-correcting turbidimeter; particle content was measured with a light-obscuration particle sizer and counter. Chemical stability was determined by measuring the concentration of each drug in the test solutions in duplicate with stability-indicating HPLC. RESULTS: Fentanyl citrate was rapidly lost when admixed with fluorouracil in polyvinyl chloride (PVC) containers, losing about 25% in the first 15 minutes and about 50% in the first hour. The loss of fentanyl citrate was so rapid that accurate time zero determinations were not possible. The extent of fentanyl loss increased with time and occurred more rapidly at the higher temperatures (i.e., 23, 32 degrees C). Losses of 70% or more occurred in all samples within 24 hours. Fentanyl underwent rapid sorption to the containers at the high pH (9.0-9.5) of the fluorouracil admixtures. Adjusting the pH of a fentanyl citrate solution (containing no fluorouracil) in PVC containers to pH 9 with sodium hydroxide also resulted in rapid sorption loss. Fentanyl citrate sorption did not occur when admixtures were prepared in polyethylene containers. Fluorouracil remained stable for at least 7 days at all temperatures. There were no visual or subvisual changes in turbidity or particle content in any of the test solutions at any time. CONCLUSIONS: When admixed with fluorouracil 1 and 16 mg/mL in dextrose 5% injection and sodium chloride 0.9% injection, fentanyl citrate 12.5 micrograms/mL underwent rapid and extensive loss due to sorption to the PVC containers, making the combination unacceptable within minutes of mixing. The sorption results from the alkaline pH of the admixture and, presumably, could occur from the admixture of fentanyl citrate with any sufficiently alkaline drug.

Analgesics, Opioid↗
PubMed1982

The use of fibronectin-coated polyvinyl chloride microtest plates to detect monoclonal antibody-binding to adherent tumor cells.

This report describes the use of fibronectin-coated polyvinyl chloride (PVC) plates as a time-saving modification in an assay measuring antibody-binding to live adherent tumor cells. Three cell lines (A-431, Colo 16 and UCLA-SO-P3) derived from human squamous cell carcinomas (SCC) and forming monolayers in cultures were plated onto flexible PVC microtest plates rather than the commonly used rigid polystyrene plates. In PVC plates, two of the three cell lines (A-431 and Colo 16) grew as foci of clumped cells instead of monolayers. Coating of the plates with plasma fibronectin restored the monolayer morphology. [125I]Staphylococcal protein A radioimmunoassays measuring the binding of a monoclonal anti-beta 2 microglobulin antibody to the cells were slightly, but consistently, more sensitive in coated PVC plates than in polystyrene plates. In contrast, the sensitivity of the radioimmunoassay was remarkably constant when the assay was performed on the third cell line (UCLA-SO-P3), which formed monolayers in any of the conditions tested. Preliminary experiments suggested that the inability to form monolayers on uncoated PVC plates correlates with the amount of fibronectin associated with the cell surface.

Antibodies, Monoclonal↗
PubMed1996

Stability of levofloxacin in intravenous solutions in polyvinyl chloride bags.

The stability of levofloxacin in 10 commonly used infusion fluids was studied. Levofloxacin 25-mg/mL injection was diluted to 0.5 and 5 mg/mL in each of the following i.v. infusion fluids: 0.9% sodium chloride injection, 5% dextrose injection, 5% dextrose and 0.9% sodium chloride injection, 5% dextrose and lactated Ringer's injection, 5% sodium bicarbonate injection, Plasma-Lyte 56 and 5% dextrose injection, 5% dextrose and 0.45% sodium chloride and 0.15% potassium chloride injection, 1/6 M sodium lactate injection, sterile water for injection, and 20% mannitol injection. Ten polyvinyl chloride bags were prepared for each solution; two were stored for 3 days at 25 degrees C, two for 7 days at 5 degrees C, two for 14 days at 5 degrees C, two for 13 weeks at -20 degrees C followed by 14 days at 5 degrees C, and two for 26 weeks at -20 degrees C, all in the dark. The solutions were visually examined, tested for turbidity and particulate matter, and subjected to stability-indicating high-performance liquid chromatography; solution pH was determined. Levofloxacin was stable in and compatible with all but two of the diluents tested. Precipitation occurred under all conditions in 20% mannitol injection for the 0.5-mg/mL levofloxacin concentration and after storage for 13 weeks at -20 degrees C for the 5-mg/mL concentration. Levofloxacin 0.5 mg/mL in 5% sodium bicarbonate injection formed a precipitate when stored at -20 degrees C for 13 weeks and beyond. Levofloxacin 0.5 and 5 mg/mL was compatible with and stable in 8 of the 10 infusion fluids studied.

Anti-Infective Agents↗