Evaluation of the light scattering and the turbidity microtiter plate-based methods for the detection of the excipient-mediated drug precipitation inhibition.
The excipient-mediated precipitation inhibition is classically determined by the quantification of the dissolved compound in the solution. In this study, two alternative approaches were evaluated, one is the light scattering (nephelometer) and other is the turbidity (plate reader) microtiter plate-based methods which are based on the quantification of the compound precipitate. Following the optimization of the nephelometer settings (beam focus, laser gain) and the experimental conditions, the screening of 23 excipients on the precipitation inhibition of poorly soluble fenofibrate and dipyridamole was performed. The light scattering method resulted in excellent correlation (r>0.91) between the calculated precipitation inhibitor parameters (PIPs) and the precipitation inhibition index (PI(classical)) obtained by the classical approach for fenofibrate and dipyridamole. Among the evaluated PIPs AUC100 (nephelometer) resulted in only four false positives and lack of false negatives. In the case of the turbidity-based method a good correlation of the PI(classical) was obtained for the PIP maximal optical density (OD(max), r=0.91), however, only for fenofibrate. In the case of the OD(max) (plate reader) five false positives and two false negatives were identified. In conclusion, the light scattering-based method outperformed the turbidity-based one and could be reliably used for identification of novel precipitation inhibitors.
Sandoz Development Center Slovenia, Pharmaceutical and Biological Profiling, Lek Pharmaceuticals d.d., Ljubljana, Slovenia. Electronic address: petrumarija@gmail.com.
Marija
M
Petruševska
Uroš
U
Urleb
Luka
L
Peternel
D000284:Administration, Oral; D019540:Area Under Curve; D001682:Biological Availability; D002138:Calibration; D011232:Chemical Precipitation; D002626:Chemistry, Pharmaceutical / Q000379:methods; D004176:Dipyridamole / Q000737:chemistry; D005079:Excipients; D005189:False Positive Reactions; D011345:Fenofibrate / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007834:Lasers; D008027:Light; D009391:Nephelometry and Turbidimetry; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012995:Solubility; D013678:Technology, Pharmaceutical / Q000379:methods*
D005079:Excipients; D004176:Dipyridamole; D011345:Fenofibrate
AUC; Fa/FeSSIF; False positives/negatives; GIT; HTE; High-throughput; Light scattering; OD; OD(max); PI; PI(classical); PIPs; Precipitation inhibition; RNU; RNU(max); S(PI)/S(B); Screening; Turbidity; UPLC; UV; Ultraviolet; area under curve; fasted/fed state simulated intestinal fluid; gastrointestinal tract; high throughput experimentation; maximum optical density; maximum relative nephelometric unit; optical density; precipitation inhibition index; precipitation inhibition index determined by the classical approach; precipitation inhibition parameters; precipitation inhibitor to Mcllvain buffer pH 6.8 signal ratio; relative nephelometric unit; ultrapressure liquid chromatography