Acta Pharm. 69 (2019) 363-380
Original research paper
Forced degradation of
tacrolimus and the development of a UHPLC method for impurities determination
TANJA ROZMAN PETERKA, TINA TRDAN LUŠIN, JURE BERGLES, ZORAN HAM, ROK GRAHEK
and UROŠ URLEB
tanja.rozman_peterka@novartis.com
Lek Pharmaceticals
d.d., SI-1526 Ljubljana,
Slovenia
Accepted December 29, 2018
Published online January 11, 2019
An ultra-high performance liquid
chromatography method for simultaneous determination of tacrolimus impurities
in pharmaceutical dosage forms has been developed. Appropriate chromatographic
separation was achieved on a BEH C18 column using gradient elution
with a total run time of 14 min. The method was applied to analyses of
commercial samples and was validated in terms of linearity, precision,
accuracy, sensitivity and specificity. It was found to be linear, precise and
accurate in the range of 0.05 to 0.6 % of the impurities level in
pharmaceutical dosage forms. Stability indicating power of the method was
demonstrated by the results of forced degradation studies. The forced
degradation study in solution revealed tacrolimus instability under stress
alkaline, thermal, light and photolytic conditions and in the presence of a radical
initiator or metal ions. The drug was stable at pH 3–5. Solid-state degradation
studies conducted on amorphous tacrolimus demonstrated
its sensitivity to light, elevated temperature, humidity and oxidation.
Keywords: tacrolimus,
forced degradation, UHPLC, impurities, stability