Description:
Objective: To investigate kinetic changes in the spectral characteristics by Fourier Transform Infrared spectroscopy (FTIR) of water-lactose
complexes (SMC), derived during the manufacturing process of the drug, containing release-active forms of antibodies.
Methods: lactose monohydrate substance, saturated with release-active forms of affinity-purified polyclonal rabbit antibodies to recombinant human
interferon-gamma (RA forms of Abs); tablets produced from this substance by direct compression after the addition of excipients (microcrystalline cellulose,
magnesium stearate). Powdered and tableted placebo samples saturated with technologically processed water or phosphate-buffered saline, as well as with
intact ethanol were used as control. Kinetic changes in SMC were studied using an Agilent Cary 630 FTIR spectrophotometer with a diamond ATR accessory
(Agilent Technologies, USA). We used the method of X-ray fluorescence spectroscopy (EDX-7000 Shimadzu energy dispersive X-ray fluorescence
spectrometer) to track changes in the fluorescence signal at certain wavelengths. The range of measured elements–
11Na92U.
Results: Control of some technological characteristics of the obtained active substance (moisture, flowability) and dosage form (mean mass,
disintegration rate) was used as indirect indicators of quality, but they did not allow reliably distinguishing intact lactose from the saturated one.
Long-period oscillations on FTIR spectra were characteristic for all types of samples; oscillations occur at approximately two-week intervals; S/N
indices were more stable for samples of RA forms of Abs than for placebo samples. On some days, the substance saturated with RA forms of Abs
significantly differed from the intact lactose powder. The kinetics of the X-ray fluorescence intensity at certain wavelengths indicates the possibility
of a periodic cooperative trigger transition of the system. Reversible conformational transitions are observed for powders on the 30th and 130th
days (K? 3.313 keV). For tablets at K? 3.313 keV and K? 1.740 keV small changes were visualized on those days (100–110th day) when hysteresis
phenomena were recorded in the IR spectra of these samples.
Conclusion: As a result, the evidence for a long-period dramatic conformational mobility of the water-lactose complex was obtained. Based on the
data on the semiannual kinetics of IR spectra, a universal criterion for the identity of lactose powder saturated with RA forms of Abs was obtained.
Also, it was confirmed that the lactose conformation state was changed by saturation with RA forms of Abs.
Type:
Journal
Document:
Diploma III Farmasi
Date:
23-06-2024
Author:
M. A. MOROZOVA