Análise térmica aplicada à caracterização da sinvastatina em formulações farmacêuticas

Abstract

THERMAL ANALYSIS APPLIED TO SIMVASTATIN CHARACTERIZATION IN PHARMACEUTICAL FORMULATIONS. Thermogravimetry (TG) and differential scanning calorimetry (DSC) are used in pharmaceutical studies for drugs characterization, purity, formulations compatibility, polymorphism identification, stability evaluation, and thermal decomposition of drugs and pharmaceutical formulations. Simvastatin showed fusion at 138.5 ºC and thermal stability up to 248 ºC. Simvastatin was incompatible with preservative excipient butylhydroxyanisole (BHA) performing a process of crystal amorphization. The drug showed morphological polymorphism, where it has the same unit cell but with different crystal habits according to the recrystallization solvent.

Thermal Stability of Simvastatin under Different Atmospheres

“…1), which is traditionally prepared by direct alkylation of lovastatin, a similar statin obtained as a secondary metabolite from the filamentous fungus Aspergillus terreus. [7][8][9] Thermal stability studies of crystalline 10,11 and amorphous [11][12][13][14] SV from ambient temperature (∼298 K) to the melting point (∼412 K) 10,11,[15][16][17][18][19] are scarce, and, to the best of our knowledge, a detailed characterization of degradation products has not yet been reported. 20 This information is, however, very important for various aspects of SV use, such as the reliable definition of storage conditions or the development of new formulations that imply heating.…”

Simvastatin assay and dissolution studies by feasible RP-HPLC in tablets

“…[21][22][23]27 However, C8 has been chosen because separation shows a slightly lower peak retention time (t R…”

“…20,21 Furthermore, LC-MS/MS was employed to identify SIM impurities or degradation products in bulk drug or tablets dosage form. 22,23 UV spectrometry, LC-UV and LC-MS have been reported to quantify SIM associated with other drugs such as ezetimibe, gemfibrozile or in multi-drugs formulation. [24][25][26][27] A micellar electrokinetic chromatographic (MEKC) method has been employed to quantify SIM and LOV in tablets.…”

“…Acetonitrile (ACN) widely used in combination with buffer solution in mobile phases, mainly in SIM official monographs of solid dosage forms. 2,11,12,14,15,18,20,22,23,[25][26][27]29 Methanol in a binary mobile phase has been reported for SIM determination in nanoparticles (specific pharmaceutical dosage form) in the concentration range 20-80 mg mL -1 . ACN worldwide shortage has reached a very high cost in the market between years 2008 and 2009.…”

Effect of 70-kDa and 148-kDa dextran hydrogels on praziquantel solubility

“…A thermoanalytical technique commonly adopted in the pharmaceutical research area is differential scanning calorimetry (DSC), employed in the characterization of drugs, in screening studies of compatibility, purity, stability and polymorphism [27]. This technique was chosen for its several advantages such as speed, the need for only small amounts of sample and ease in identifying interactions, polymorphisms, glass transition and changes in crystalline and/or amorphous states [25].…”