Preparation and Characterization of Taxifolin Form II by Antisolvent Recrystallization

Abstract

To improve the aqueous solubility and dissolution rate of taxifolin, taxifolin form II was successfully prepared through antisolvent recrystallization, in which 1‐butyl‐3‐methylimidazolium tetrafluoroborate and dichloromethane were used as solvent and antisolvent, respectively. The properties of taxifolin form II were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, differential scanning calorimetry, solid‐state NMR spectroscopy, the dissolving capability test, and the bioavailability test. The chemical structure of taxifolin form II was not changed, but its morphology and crystalline structure changed during the recrystallization process. Moreover, taxifolin form II showed higher solubility, faster dissolution rate, and better bioavailability than taxifolin form I.

Assembling the Puzzle of Taxifolin Polymorphism

“…Taxifolin microtubes have a similar XRPD pattern when compared to raw taxifolin, but nevertheless are not identical ( Figure 5 b). Additionally, a previous article reported a so-called taxifolin form I, which has a similar XRPD pattern but is characterized by another morphology—it was described as blocks [ 40 ]. The XRPD pattern of microspheres is characterized by an amorphous halo ( Figure 5 c).…”

Bioavailability and Safety of Dihydroquercetin (Review)

“…Analogous results were reported in a monograph with a reference to an inaccessible report on preclinical pharmacokinetic studies of 2007 [23], where t 1/2 was <1.25 h after administration to rats at doses of 12.5 -50 mg/kg. Several other DHQ modifications used at a dose of 50 mg/kg gave t 1/2 values in the range 2 -3 h [24].…”

“…Later, amorphous nanoparticles that were 1.7 times more soluble, dissolved three times faster, and had seven times the peroral bioavailability than the raw material were obtained using liquid antisolvent deionized water and g-cyclodextrin cryoprotectant for lyophilization [41]. Another DHQ modification that was prepared using an ionic liquid as the solvent and dichloromethane as the antisolvent showed improved solubility by 1.26 times in artificial stomach juice as compared to the raw material [24]. The solubility of DHQ in complexes with g-cyclodextrin could be increased by 18.5 -19.8 times, the dissolution rate by 2.8 times, and the bioavailability by 3.7 times as compared to the native substance by using an emulsion solvent in combination with lyophilization [42].…”