scholarly journals Evaluations about the physico-chemical stability of docetaxel and irinotecan pre-diluted and diluted solutions: pharmaco-economic perspectives

2013 ◽  
Vol 3 (1) ◽  
pp. 6 ◽  
Author(s):  
Mariarita Laforgia ◽  
Anna Elisa Quatrale ◽  
Nicola A. Colabufo ◽  
Amalia Azzariti ◽  
Angelo Paradiso ◽  
...  
Keyword(s):  
Chemical Stability ◽  
Mobile Phase ◽  
Ammonium Acetate ◽  
Physical Stability ◽  
Experimental Conditions ◽  
Phase Gradient ◽  
Methanol Mixture ◽  
Physico Chemical ◽  
Starting Point ◽  
Economic Perspectives

Several clinically used anticancer drugs are well-known as far as their pharmacologic properties are concerned, but scarcely ever the interest towards their physico-chemical characteristics in solution led to practical acknowledgement in their management. Thanks to the Units for Centralized Anticancer Drug Handling, the importance to evaluate the concentration of saturation (physical stability) or the possible transformations undergone by a drug in solution (chemical stability) has become the starting point for avoiding useless wasting drugs and economic resources. By HPLC experiments we have demonstrated that the solutions of two drugs, docetaxel and irinotecan, are particularly stable at different concentrations and times of analyses in our experimental conditions. The best mobile phase for docetaxel was water/methanol/acetonitrile in 42/32/26 volumetric ratio: for halving concentrations (0.72-0.36-0.18-0.09 mg/mL) in NaCl 0.9%, the highest value gave a six-day and the three lower concentrations a fourteen-day stability, when storage occurred at room temperature and light protected. Elution of irinotecan was possible through an analysis in mobile phase gradient: at t0 a 20% ammonium acetate 10 mM and 80% methanol mixture, and after 5 min, a 80% ammonium acetate 10 mM and 20% methanol mixture. The physico-chemical stability was showed for five days, for any concentration of analysis when storage occurred at 2-8°C and light protected.

scholarly journals Charged aerosol detector response modeling for fatty acids based on experimental settings and molecular features: a machine learning approach

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Ruben Pawellek ◽  
Jovana Krmar ◽  
Adrian Leistner ◽  
Nevena Djajić ◽  
Biljana Otašević ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Mobile Phase ◽  
Molecular Descriptors ◽  
Attribute Selection ◽  
Selection Strategy ◽  
Detector Response ◽  
Experimental Conditions ◽  
Molecular Features ◽  
Charged Aerosol ◽  
Charged Aerosol Detector

AbstractThe charged aerosol detector (CAD) is the latest representative of aerosol-based detectors that generate a response independent of the analytes’ chemical structure. This study was aimed at accurately predicting the CAD response of homologous fatty acids under varying experimental conditions. Fatty acids from C12 to C18 were used as model substances due to semivolatile characterics that caused non-uniform CAD behaviour. Considering both experimental conditions and molecular descriptors, a mixed quantitative structure–property relationship (QSPR) modeling was performed using Gradient Boosted Trees (GBT). The ensemble of 10 decisions trees (learning rate set at 0.55, the maximal depth set at 5, and the sample rate set at 1.0) was able to explain approximately 99% (Q2: 0.987, RMSE: 0.051) of the observed variance in CAD responses. Validation using an external test compound confirmed the high predictive ability of the model established (R2: 0.990, RMSEP: 0.050). With respect to the intrinsic attribute selection strategy, GBT used almost all independent variables during model building. Finally, it attributed the highest importance to the power function value, the flow rate of the mobile phase, evaporation temperature, the content of the organic solvent in the mobile phase and the molecular descriptors such as molecular weight (MW), Radial Distribution Function—080/weighted by mass (RDF080m) and average coefficient of the last eigenvector from distance/detour matrix (Ve2_D/Dt). The identification of the factors most relevant to the CAD responsiveness has contributed to a better understanding of the underlying mechanisms of signal generation. An increased CAD response that was obtained for acetone as organic modifier demonstrated its potential to replace the more expensive and environmentally harmful acetonitrile.

scholarly journals Tailoring of Hydrotalcite-Derived Cu-Based Catalysts for CO2 Hydrogenation to Methanol

Catalysts ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1058 ◽  
Author(s):  
Leone Frusteri ◽  
Catia Cannilla ◽  
Serena Todaro ◽  
Francesco Frusteri ◽  
Giuseppe Bonura
Keyword(s):  
Metallic Copper ◽  
Chemical Properties ◽  
Active Phase ◽  
Co2 Hydrogenation ◽  
High Dispersion ◽  
Experimental Conditions ◽  
Typical Structure ◽  
Methanol Production ◽  
Physico Chemical ◽  
Space Time Yield

Ternary CuxZnyAlz catalysts were prepared using the hydrotalcite (HT) method. The influence of the atomic x:y:z ratio on the physico-chemical and catalytic properties under CO2 hydrogenation conditions was probed. The characterization data of the investigated catalysts were obtained by XRF, XRD, BET, TPR, CO2-TPD, N2O chemisorption, SEM, and TEM techniques. In the “dried” catalyst, the typical structure of a hydrotalcite phase was observed. Although the calcination and subsequent reduction treatments determined a clear loss of the hydrotalcite structure, the pristine phase addressed the achievement of peculiar physico-chemical properties, also affecting the catalytic activity. Textural and surface effects induced by the zinc concentration conferred a very interesting catalyst performance, with a methanol space time yield (STY) higher than that of commercial systems operated under the same experimental conditions. The peculiar behavior of the hydrotalcite-like samples was related to a high dispersion of the active phase, with metallic copper sites homogeneously distributed among the oxide species, thereby ensuring a suitable activation of H2 and CO2 reactants for a superior methanol production.

SIMULTANEOUS ESTIMATION OF CURCUMIN AND GEFITINIB IN BULK AND TISSUE SAMPLES (PLASMA AND BRAIN HOMOGENATE) BY RP-HPLC: APPLICATION TO A DISTRIBUTION STUDY

INDIAN DRUGS ◽  
2019 ◽  
Vol 56 (07) ◽  
pp. 59-68
Author(s):  
H Mahajan ◽  
S Savale ◽  
P Nerkar ◽  
Keyword(s):  
Flow Rate ◽  
Mobile Phase ◽  
Internal Standard ◽  
Brain Homogenate ◽  
Reversed Phase ◽  
Hplc Method ◽  
Simultaneous Estimation ◽  
Bulk Analysis ◽  
Experimental Conditions ◽  
Rp Hplc

The present study was aimed at developing a Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC) method for simultaneous determination of curcumin (CRM) and gefitinib (GFT) in bulk, plasma and brain homogenate. hydrochlorothiazide was used as an internal standard (IS). A new simple, rapid, selective, precise and accurate RP-HPLC method has been developed. The separation was achieved by using C-18 column (Qualisil BDS C18, 250 mm x 4.6 mm I.D.) coupled with a guard column of silica, mobile phase consisted of acetonitrile: water with 0.1% formic acid (30:70 v/v). The flow rate was 0.2 ml/min and the drug was detected using PDA detector at the wavelength of 242 nm. The experimental conditions, including the diluting solvent, mobile phase composition, column saturation and flow rate, were optimised to provide high-resolution and reproducible peaks. The method was developed and tested for linearity range of 10-60 μg/mL for bulk analysis and 200-800 ng/mL for plasma and brain homogenate. The developed method was validated as per ICH guidelines, in terms of linearity, application of the proposed method to bulk sample, recovery, precision, repeatability, ruggedness, sensitivity (LOD and LOQ) and robustness and stability study (short and long-term stabilities, freeze/thaw stability, post-preparative). The low value of % RSD showed that the method was precise within the acceptance limit of 2%. The developed method was successfully applied for the analysis of the drug in bulk as well as various marketed formulation and drug in plasma and brain distribution studies.

Physico‐chemical stability of Plasma‐Lyte 148® and Plasma‐Lyte 148® + 5% Glucose with eight common intravenous medications

2019 ◽  
Vol 29 (2) ◽  
pp. 186-192
Author(s):  
Rachael Dawson ◽  
Andrew Wignell ◽  
Paul Cooling ◽  
David Barrett ◽  
Harish Vyas ◽  
...  
Keyword(s):  
Chemical Stability ◽  
Physico Chemical

Physico-chemical stability of casein micelles cross-linked by transglutaminase as a function of acidic pH

2019 ◽  
Vol 19 ◽  
pp. 100103 ◽  
Author(s):  
Márcio H. Nogueira ◽  
Guilherme M. Tavares ◽  
Naaman F. Nogueira Silva ◽  
Federico Casanova ◽  
Paulo C. Stringheta ◽  
...  
Keyword(s):  
Chemical Stability ◽  
Acidic Ph ◽  
Casein Micelles ◽  
Physico Chemical

scholarly journals High-performance liquid chromatography of uroporphyrinogen and coproporphyrinogen isomers with amperometric detection

1986 ◽  
Vol 234 (3) ◽  
pp. 629-633 ◽  
Author(s):  
C K Lim ◽  
F Li ◽  
T J Peters
Keyword(s):  
Mobile Phase ◽  
High Performance ◽  
Ammonium Acetate ◽  
Amperometric Detection ◽  
Reversed Phase ◽  
Fluorescent Detection ◽  
Organic Modifiers ◽  
Ammonium Acetate Buffer ◽  
Effects Of Ph ◽  
Ph Buffer

A reversed-phase h.p.l.c. system, with an ODS-Hypersil column with acetonitrile or methanol in ammonium acetate buffer as mobile phase, is described for the separation of uro-and copro-porphyrinogen isomers. The porphyrinogens are detected amperometrically with sensitivity comparable with that of the fluorescent detection of porphyrins. The effects of pH, buffer concentration and organic modifiers on retention and resolution were studied. The method is suitable for both analytical and preparative separation of porphyrinogens.

AMPHOTERICIN B TOPICAL EXTEMPORANEOUS PREPARATIONS FOR THE TREATMENT OF NON-DERMATOPHYTIC ONYCHOMYCOSIS

2020 ◽  
pp. 135-139
Author(s):  
KOMESMUNEEBORIRAK PHOJANA ◽  
WERAWATGANONE PORNPEN ◽  
MUANGSIRI WALAISIRI
Keyword(s):  
Amphotericin B ◽  
Chemical Stability ◽  
High Performance ◽  
Sodium Lauryl Sulfate ◽  
Physical Stability ◽  
Lauryl Sulfate ◽  
Physical And Chemical ◽  
Injection Product

Objective: At present, the nail preparation to cure onychomycosis, caused by non-dermatophyte molds, is not commercially available in Thailand. The physical and chemical stability of amphotericin B (AmB) extemporaneous preparations in the presence of 30% dimethyl sulfoxide (DMSO) and their in vitro nail permeation was evaluated. Methods: AmB extemporaneous preparations in the presence of 30% DMSO were prepared from a commercial sterile injection product, and cream or hydrophilic ointment. Physical stability was tested at 30°C for 2 months, or using 6 heating-cooling cycles. The chemical stability and in vitro nail permeation of AmB content were analyzed using high-performance liquid chromatography (HPLC). In vitro nail permeation was performed by applying 3.5 mg/mm2 of the tested formulation on nail clippings for 5 consecutive days. Results: The AmB cream and ointment extemporaneous preparations containing 30% DMSO, a permeation enhancer, were homogeneous and pale yellow to yellow cream or ointment. The AmB ointment was stable for up to 60 days. The ointment preparation allows in vitro penetration through nails up to 14.17 μg/cm2. The ointment preparation allows significantly better penetration through than the cream preparation due to the presence of DMSO, sodium lauryl sulfate (SLS), and water in the ointment preparation. Conclusion: The AmB extemporaneous ointment was successfully compounded from a commercial sterile injection product with a beyond-use date of 60 days. The ointment preparation is currently under further investigation for in vivo efficacy.

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