INVESTIGADORES
ISLAN German Abel
congresos y reuniones científicas
Título:
Development and validation of a HPLC-UV method for determination of Levofloxacin in lung tissue. Application to the quantification of the drug after nasal administration into biopolymeric microparticles
Autor/es:
RUIZ MA; MORALES JF; ENRIQUE AV; SBARAGLINI ML; TALEVI A; ISLAN GA; CACICEDO ML; BRUNO-BLANCH LE; CASTRO GR
Lugar:
Córdoba
Reunión:
Encuentro; 3ra Reunión Internacional de Ciencias Farmacéuticas - RICIFA 2014-; 2014
Institución organizadora:
RICIFA 2014
Resumen:
A HPLC-UV method for determination of Levofloxacin
(LFX) in mouse lung tissue was developed and validated. Conditions: C18 column,
acetonitrile/KH2PO4 30 mM pH 2.80 (22/78) mobile phase, 1.0
ml/min and 300 nm detection. Enrofloxacin (EFX) was used as internal standard
(IS). For sample preparation, excised mouse lungs were homogenized, spiked with
IS and diluted in 2 ml of physiologic solution. After 24 hs at 4 °C, two 0.9
ml-aliquots were extracted with 2 ml of dichloromethane and centrifuged. The
organic layer was separated and evaporated to dryness, and the residue resuspended
with 200 μl of mobile phase prior to injection.
In an initial validation stage, samples were prepared
in blank homogenized lung tissue by the addition of known concentrations of LFX
and EFX in methanolic solution, and linearity, precision, accuracy, limit of
quantification (LQ), specificity and stability were assessed. The response was
linear in the range 0,02 (LQ) ? 15.00 μg/ml. Precision RSD values were < 4.0% and accuracy
was between 90?100%. The method was specific to the biological matrix, and the
drugs were stable in methanolic solution, biological matrix and prepared
samples. The recovery was around 70% due to the drug loss in the lung tissue,
since the extraction procedure had a 95-100% recovery. Microparticles were
prepared by co-precipitation of CaCO3 in presence of the alginate
biopolymer. The obtained hybrid microparticles showed narrow size dispersion
around 5 μm, an ideal size for pulmonary delivery. LFX was
incorporated by absorption, reaching a loading of 40.0 µg per mg of matrix.
Therefore, in a second validation stage, all validation parameters were re-assessed
using these microparticles instead of the methanolic solution, and similar
results were obtained.
Finally, the method was successfully applied to the
quantification of LFX in mouse lungs after the nasal administration of the
polymeric microparticles.