Forced degradation of tacrolimus and the development of a UHPLC method for impurities determination

Abstract

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.

Stability characterization, kinetics and mechanism of tacrolimus degradation in cyclodextrin solutions

“…Besides these, a different kind of equilibrium exists in polar solvents with respect to cyclic ketal moiety. This equilibrium is explained by tautomerism of tacrolimus where tacrolimus epimerizes to an intermediate tautomer I(ring-opened tacrolimus) which is then converted to tautomer II to reach an equilibrium containing the three forms (Skytte, 2013;Namiki, 1993;Peterka, 2019).…”

Physicochemical Stability of a Novel Tacrolimus Ophthalmic Formulation for the Treatment of Ophthalmic Inflammatory Diseases

“…The quantification method used was directly transposed from the stability indicating ultra-high performance liquid chromatography (UHPLC) method published by Peterka et al [25], after minor adaptations from UHPLC to high performance liquid chromatography (HPLC). The HPLC separation column used was a Kinetex ® Core-Shell 2.6 µm EVO C18 100 Å, 100 mm × 3 mm, reference 00D-4725-Y0, (Phenomenex, Le Pecq, France), with an associated security guard ULTRA EVO-C18 sub2 µm-Coreshell reference AJ0-9296 (Phenomenex, Le Pecq, France).…”

“…The HPLC separation column used was a Kinetex ® Core-Shell 2.6 µm EVO C18 100 Å, 100 mm × 3 mm, reference 00D-4725-Y0, (Phenomenex, Le Pecq, France), with an associated security guard ULTRA EVO-C18 sub2 µm-Coreshell reference AJ0-9296 (Phenomenex, Le Pecq, France). This column has an equivalent stationary phase to that used by Peterka et al [25] (C18 phase, USP L1 classification). Due to the modification of the column granulometry, the flow rate was increased to 1 mL/min and the mobile phase gradient was lengthened.…”

“…The gradient used is presented in Table 3. In order to verify the correct transposition of the method and to allow the identification as proposed in the original method of tacrolimus and its equilibrium compounds I and II, related substances and byproducts (ascomycin) and breakdown products (tacrolimus alpha-hydroxy acid and tacrolimus regioisomer), the relative retention times of tacrolimus and ascomycin (impurity A) were checked against those obtained by Peterka et al [25]. These compounds were analysed as recommended by the tacrolimus European Pharmacopoeia monography [26].…”

A Novel Validated Uhplc Method for Estimation of Assay and Its Related Substances of Trichostatin-A

“…By applying UHPLC concepts, it can reduce the run times of chromatographic methods and effluents and decrease the turnaround times [4][5][6]. Various UHPLC methods have been developed for the determination of related compounds and potency of the drug in pharmaceutical drug substances and formulations and many bioanalytical methods were developed to estimate the drug content in the pharmacy kinetic study and dietary samples [7][8][9][10].…”