Study of tocopherol content and its potential antioxidant activity in commercial lipid emulsions for parenteral nutrition

The objective of this study was to determine the content and evaluate the potential antioxidant effect of tocopherols in commercially available lipid emulsions, using a simple validated method adequate for further routine use. During the study, variability between manufacturers as well as between three non-consecutive batches of the same emulsion was observed. Furthermore, addition of α-tocopherol to lipid emulsions as excipient yields more stable emulsions and potentially a beneficial clinical effect. It was concluded that the variation of the tocopherol content between batches implies the importance of control and specification of tocopherol content by the manufacturers.

Improving tablet coating robustness by selecting critical process parameters from retrospective data

CONTEXT

Although tablet coating processes are widely used in the pharmaceutical industry, they often lack adequate robustness. Up-scaling can be challenging as minor changes in parameters can lead to varying quality results.

OBJECTIVE

To select critical process parameters (CPP) using retrospective data of a commercial product and to establish a design of experiments (DoE) that would improve the robustness of the coating process.

MATERIALS AND METHODS

A retrospective analysis of data from 36 commercial batches. Batches were selected based on the quality results generated during batch release, some of which revealed quality deviations concerning the appearance of the coated tablets. The product is already marketed and belongs to the portfolio of a multinational pharmaceutical company.

RESULTS

The Statgraphics 5.1 software was used for data processing to determine critical process parameters in order to propose new working ranges.

DISCUSSION AND CONCLUSIONS

This study confirms that it is possible to determine the critical process parameters and create design spaces based on retrospective data of commercial batches. This type of analysis is thus converted into a tool to optimize the robustness of existing processes. Our results show that a design space can be established with minimum investment in experiments, since current commercial batch data are processed statistically.

Studies on the codling moth (Lepidoptera: Tortricidae) response to different codlemone release rates

The response of the codling moth (Cydia pomonella L. (Lepidoptera: Tortricidae)) to different emission values of its main pheromone component, 8E,10E-dodecadien-1-ol (codlemone), was investigated in three field trials conducted in plots without mating disruption treatments. Moth catches obtained in traps baited with pheromone dispensers were correlated with the corresponding codlemone release rates by multiple regression analysis. In a preliminary trial conducted in Lleida (NE Spain), a decreasing trend of captures was observed based on increasing pheromone levels. After this, the pheromone release profiles of the pheromone dispensers were studied, in parallel with the field trials, by residual codlemone extraction and gas chromatography quantification. In the trials carried out in Asturias (NW Spain), a correlation between trap catches and emission levels (within the range from 11 to 1,078 μg/d) was found and fitted a logarithmic model. Captures followed a decreasing linear trend in the range of emission rates from 11 to 134 μg/d. Given that release values comprised between 11 and 67 μg/d did not lead to significantly different catches in traps, this emission range could be considered to develop effective formulations for attraction purposes when mating disruption is not acting in the environment.

Total organic carbon (VCSN and VWP) and HPLC analysis for cleaning validation in a pharmaceutical pilot plant

This paper presents a useful method using total organic carbon analyzers employing both combustion and wet oxidation for validating equipment cleaning procedures and verifying cleaning in a pharmaceutical pilot plant. The results are compared with those obtained using high-performance liquid chromatography. The study summarizes the initial steps that should be taken into account and focuses particularly on the solutions to some of the most critical considerations (e.g., glass material, detection and quantification limits, recovery). Also described are the calculation of control limits and the good results obtained.

Method for the development of topical medicinal aerosols using liquified hydrocarbon gas

Low chain liquid hydrocarbons (LH) at room temperature and atmospheric pressure can be used to simulate the effect of gas hydrocarbons (GH) in aerosol systems without the need of using pressured flasks. Samples of different tetracycline formulations were tested with LH and GH in order to study their behaviour and physicochemical stability in the system. The results showed a similar behaviour between samples when LH or GH were used, suggesting the use of LH to simulate the effect of GH introduction in the system, as a useful predictive method for the development of pressured aerosol formulations without using pressured containers in early steps of the process, such as pre-formulation studies.

Resistance of apple cultivars to Dysaphis plantaginea (Hemiptera: Aphididae): role of tree phenology in infestation avoidance

To test the importance of flowering phenology in damage caused to apple cultivars by rosy apple aphid, Dysaphis plantaginea (Passerini) (Hemiptera: Aphididae), susceptibility of 16 cultivars was compared in greenhouse conditions after infestation with aptera and in the field after natural tree colonization. Flowering phenology was recorded in the field for all the cultivars. In both greenhouse and field trials, there were differences among cultivars with respect to aphid infestation and damage. However, damage in the greenhouse and field was not significantly correlated. Flowering phenology was also different among cultivars. Flowering order among cultivars was significantly negatively correlated with aphid infestation and damage in field, i.e., early leafing cultivars showed higher infestation and damage than late-leafing cultivars. If egg hatching occurs before bud bursting, neonate larvae will suffer a high mortality because they cannot feed on these late cultivars. A later recolonization of these trees is hampered because (1) winged aphids cannot live on apple but only on the secondary host, (2) apterous forms have a limited dispersal capability, and (3) aphid predators progressively increase in the orchard. Therefore, synchronization between egg hatching and bud bursting is of critical importance in the success or failure of infestation.

Stability evaluation of amoxicillin in a solid premix veterinary formulation by monitoring the degradation products through a new HPLC analytical method

A methodology (by VICH guidelines) for the stability evaluation of amoxicillin in granular premixes is described. This method is based on the monitoring of the degradation products formed during the stability study by a new HPLC-RP method, which has been developed and validated for the simultaneous determination of amoxicillin and its degradation products. The method uses a Nucleosil 120 C18 column and gradient elution. The mobile phase consisted of a mixture of methanol and buffer solution pH 3+/-0.05 at different proportion according to a time-schedule programme, pumped at a flow rate of 1.750 ml min(-1). The DAD detector was set at 230 nm. The validation study was carried out fulfilling the VICH guidelines in order to prove that the new analytical method, meets the reliability characteristics, and these characteristics showed the capacity of analytical method to keep, throughout the time, the fundamental criteria for validation: selectivity, linearity, precision, accuracy, sensitivity (LOD, LOQ) and robustness. The method was applied during the stability study of an amoxicillin premix in order to quantify the drug (amoxicillin) and all its degradation products to evaluate the shelf life of the new veterinary dosage form. The method also proved to be suitable as a rapid and reliable quality control method.

A new validated method for the simultaneous determination of benzocaine, propylparaben and benzyl alcohol in a bioadhesive gel by HPLC

A new HPLC-RP method has been developed and validated for the simultaneous determination of benzocaine, two preservatives (propylparaben (nipasol) and benzyl alcohol) and degradation products of benzocaine in a semisolid pharmaceutical dosage form (benzocaine gel). The method uses a Nucleosil 120 C18 column and gradient elution. The mobile phase consisted of a mixture of methanol and glacial acetic acid (10%, v/v) at different proportion according to a time-schedule programme, pumped at a flow rate of 2.0 ml min(-1). The DAD detector was set at 258 nm. The validation study was carried out fulfilling the ICH guidelines in order to prove that the new analytical method, meets the reliability characteristics, and these characteristics showed the capacity of analytical method to keep, throughout the time, the fundamental criteria for validation: selectivity, linearity, precision, accuracy and sensitivity. The method was applied during the quality control of benzocaine gel in order to quantify the drug (benzocaine), preservatives and degraded products and proved to be suitable for rapid and reliable quality control method.

Development and validation of a new HPLC analytical method for the determination of alprazolam in tablets

A new analytical method is developed together with its latter validation study, by means of a high resolution liquid chromatography (HPLC) of reverse phase to quantify alprazolam (8-chloro-1-methyl-6-phenyl-4H-[1,2,4] triazole [4,3,-alpha]-[1,4] benzodiazepine) in tablets. Determination is carried out by means of an ODS C18 column (200 mm x 4.6 mm i.d., 5 microm particle size); the mobile phase consisted of a mixture of 0.02 M buffer solution of phosphates (pH 6.0) and acetonitrile (45:55, v/v). It is pumped through the chromatographic system at a flow rate of 0.50 ml min(-1). The UV detector is operated at 254 nm. The validation study is carried out fulfilling the ICH guidelines in order to prove that the new analytical method, meets the reliability characteristics, and these characteristics show the capacity of an analytical method to keep, throughout the time, the fundamental criteria for validation: selectivity, linearity, precision, accuracy and sensitivity. The method is applied during the working day for the quality control of commercial alprazolam tablets in order to quantify the drug and its degradation products and to check the content uniformity test.

Study of formulation parameters by factorial design in metoprolol tartrate matrix systems

The study of formulation parameters in hydrophilic matrices of metoprolol tartrate by 2(3) factorial design wass made. We compared the dissolution profiles of two hydrophilic polymers (hydroxypropylmethylcellulose and hydroxyethylcellulose) at high and low concentrations and in the presence or absence of an insoluble excipient (calcium hydrogen phosphate dihydrate). The results showed that the presence of an insoluble excipient influenced almost all of the dissolution parameters.