Stability study of fluconazole applying validated bioassay and stability-indicating LC methods

Chemical degradation of drugs may result in altered therapeutic efficacy and even toxic effects. Therefore, understanding the factors that change the stability of pharmaceuticals and identifying ways to guarantee their stability are important. In this work stability-indicating Liquid Chromatographic (LC) and bioassay methods were validated and employed in the fluconazole stability studies. The correlation of sample results from both methods was evaluated. Fluconazole raw material stability was investigated in aqueous, acid (0.1 M HCl), alkaline (0.1 M NaOH) and oxidative (3% v/v H2O2) reflux for 6 hours, by LC method. Fluconazole capsules were exposed to UVC (254 nm, 66 and 180 days), climatic chamber (40°C, 75% RH, 90 days) and oven (60°C, 60 days), these samples were analyzed by LC and bioassay methods It was found that the drug is degraded (10% decrease) with arising of a possible degradation product in an oxidative medium and UVC exposure, in all the others conditions fluconazole remained chemically stable (higher than 98%) when analyzed by LC. However when the capsules stressed samples were evaluated through bioassay very low antifungal activity was found (about 30%). Fluconazole showed to be an unstable drug and it indicates that special care must be taken during the handling, storage and quality control using appropriated methods to analyze this therapeutic agent. This work suggests monitoring the fluconazole stability by bioassay and the stability-indicating LC methods.

Physico-chemical characterization and analytical development for sodium azumolene, a potential drug designed to fight malignant hyperthermia

Sodium azumolene is a drug designed to fight Malignant Hyperthermia (MH), which is characterized by genetic predisposition and triggered by the use of inhalational anesthetics. This drug is shown as a water-soluble analogue of dantrolene sodium, 30-folds more water soluble, which gives advantages for its emergency use. To our knowledge there is no analytical method for sodium zaumolene raw material or dosage form published so far. The objective of the present investigation was to develop and validate analytical methods to achieve sodium azumolene chemical identification and quantification. The sodium azumolene was characterized regarding its thermal behavior, by differential thermal analysis and thermogravimetric analysis; Visible, UV and infrared absorption. To accurately assess the sodium Azumolene content three different analytical methods (visible and UV spectrophotometry and high performance liquid chromatography) were developed and validated. All methods showed to be linear, accurate, precise and reliable. Azumolene has shown to be equipotent to dantrolene in the treatment and prevention of an MH crisis and the great advantage compared to dantrolene is better water solubility. This study has characterized the sodium azumolene and presents new analytical methods which have not been reported so far.

Tobacco in adolescence: importance to knowledge the health hazards and preventive measures

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Microbiologic characterization of equine mastitis

Mastitis occurrence in mares is low if compared to other livestock species. The microorganisms often isolated and detected in milk and mammary gland secretions of mares are Streptococcus beta-haemolytica, Staphylococcus spp., Pseudomonas aeruginosa, Actinobacillus spp., and enterobacter. The present experiment was designed to evaluate the main microorganisms present in the milk of healthy mares and having a mammary infection. One hundred and ten mammary glands from 55 lactating mares were analyzed, ranging from 15 to 150 d post-partum. The mastitis diagnostic was performed through analysis of the milk via the screened test of the mug with dark background (Tamis), mammary gland inflammation and/or systemic signs. The subclinical mammary gland infection was characterized via the California Mastitis Test (CMT). From the 55 lactating mares, 2 (3.64%) had clinical mastitis. Following the CMT, the mares presented: 13 (23.60%), 7 (12.72%), and 12 (21.88%) scores from 1+, 2+, and 3+, respectively. From the 110 mamary glands were analysed, in 47 (85.45%) of these samples strains of microorganisms were isolated. In summary, results from our experiment suggest a low occurrence of clinical mastitis in lactating mares.

Expression of growth-related factors in skeletal muscle of Pirarucu (Arapaima gigas) during growth

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of quercetin administration on the pregnancy outcome of diabetic rats

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)