Biomedical subjects

G A Pianetti

Publications and source records attributed to G A Pianetti.

3 recordsLinked to original sources

PubMed2006

The influence of formulation on the dissolution profile of diclofenac sodium tablets.

In attempts to design delayed-release tablets of diclofenac sodium, seven experimental batches were produced. The influence of super-disintegrant croscarmellose sodium (CCS), the granulation process, and the thickness of Eudragit L 100 coating film were evaluated. The values of dissolution efficiency and the similarity factor were used to compare the dissolution profiles of each experimental batch and the reference Voltaren. Both methods appear to be applicable and useful in comparing dissolution profiles. Based on such values four batches were considered similar when contrasted with the reference. The results suggest an optimal relationship between the amount of CCS and the thickness of the coating film, which provides appropriate dissolution rate of diclofenac sodium from the dosage forms.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2004

Optimization and statistical evaluation of dissolution tests for indinavir sulfate capsules.

An optimization, statistically based on t-student test, to set up dissolution test conditions for indinavir sulfate capsules is presented. Three dissolution media, including that reported in United States Pharmacopeial Forum, and two apparatus, paddle and basket, were applied. Two different indinavir sulfate capsules, products A and B, were evaluated. For a reliable statistical analysis eighteen capsules were assayed in each condition based on the combination of dissolution medium and apparatus. All tested media were statistically equivalent (P > 0.05) for both drug products when paddle apparatus was employed at the stirring speed of 50 rpm. The use of basket apparatus at the stirring speed of 50 rpm caused significant decrease in the drug release percent for the product B (P < 0.05). The best dissolution conditions tested, for products A and B, were applied to evaluate capsules dissolution profiles. Twelve dosage units were assayed and dissolution efficiency concept was used, for each condition, to obtain results with statistical significance (P > 0.05). Optimal conditions to carry out the dissolution test were 900 ml of 0.1 M hydrochloric acid as dissolution medium, basket at 100 rpm stirring speed and 260 nm ultraviolet detection.

Capsules↗

PubMed1993

Fosfomycin determination in serum by capillary zone electrophoresis with indirect ultraviolet detection.

Capillary zone electrophoresis with indirect ultraviolet detection was used for the determination of fosfomycin in serum. Running buffer consisted of a mixture of 200 mM sodium borate with 10 mM phenylphosphonic acid used as ultraviolet absorbing background electrolyte. Relationships between the pH of the buffer and the efficiency of the separation (migration times and selectivities) or the sensitivity of detection were investigated. The method was then validated over a 10-100 micrograms ml-1 concentration range to be applied to further therapeutic drug monitoring. The choice of ethylphosphonic acid as internal standard is discussed. The specificity and the linearity of the technique are demonstrated. The inter-day precision was satisfactory with a relative standard deviation of less than 2%. Accuracy was calculated with a standard error near 0.5 and 18% for 100 and 10 micrograms ml-1, respectively.

Electrolytes↗