A Validated Quantification of Benzocaine in Lozenges Using TLC and a Flatbed Scanner
Milz, B; Spangenberg, B
| HERO ID | 2288061 |
|---|---|
| In Press | No |
| Year | 2013 |
| Title | A Validated Quantification of Benzocaine in Lozenges Using TLC and a Flatbed Scanner |
| Authors | Milz, B; Spangenberg, B |
| Journal | Chromatographia |
| Volume | 76 |
| Issue | 19-20 |
| Page Numbers | 1307-1313 |
| Abstract | We present a video-densitometric quantification method for benzocaine in lozenges. The quantification is based on a derivatisation reaction with 4-dimethylaminobenzaldehyde. Measurements were carried out using a 16-bit flatbed scanner. Benzocaine was separated to a distance of 50 mm in a vertical developing chamber without vapour saturation. We present an RP-18 phase separation on a cyanopropyl plate (Merck, Darmstadt, Germany) using water, CH3CN, dioxane, ethanol, and NH3 (25 %) (8 + 2 + 1 + 1 + 0.05, v/v) as the mobile phase. We also separated benzocaine in a normal phase system on silica gel 60 LiChrospere(A (R)) plates (Merck, Darmstadt, Germany) with the mobile phase MTBE/cyclohexane (1 + 1, v/v). The calibration functions for benzocaine in both separations were linear in the range from 1 to 1,000 ng per spot. The range of linearity covers two magnitudes of power because the Kubelka-Munk expression was used for data transformation. In the cyanopropyl-system, the benzocaine amount was quantified as 242.5 +/- A 18.2 ng in a spot or 6.86 +/- A 0.52 mg in a single lozenge. The amount of 7.0 mg benzocaine per lozenge was labelled. The combined uncertainty of sample and calibration measurements was statistically calculated using a significance level of alpha = 0.05 to a total relative uncertainty of 7.49 %. The separation method is inexpensive, fast and reliable. |
| Doi | 10.1007/s10337-013-2436-4 |
| Wosid | WOS:000324825100012 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Keyword | High performance thin-layer chromatography (HPTLC); Thin-layer chromatography (TLC); Benzocaine; Quantification; Video densitometry; Flatbed scanner; Diode-array detection; Large linear calibration range |