FT-Raman spectroscopy based on band intensity or band area measurements was used for the quantitative determination of ciprofloxacin in pharmaceutical solid dosage forms. Univariate calibration was used for quantitative analysis. Bands observed at 1708, 1624, 1548, 1493, 1273, 1253, 1238, 1024, 805, 787, 752, 718, 665, and 638 cm−1 were used. Calibration curves were linear in the concentration range of 3–100% w/w with correlation coefficients of 0.99–0.996 and 0.991–0.9993 for band intensity and band area measurements, respectively. Precision ranged from 0–11 and 0.4–12% relative standard deviation (RSD) (n = 3) for band intensity and band area measurements, respectively, and results were in good agreement with the results obtained by the current United States Pharmacopoeia (USP 24) and National Formulary (NF 19) method. Multivariate calibration was also used for quantitative analysis. Multiple linear regression using the intensities of the 1545 and 1272 cm−1 bands gave results in accordance with those obtained by the current United States Pharmacopoeia (USP 24) and National Formulary (NF 19) method. As measurement takes just 30 s using the analytical readout from a single band, the proposed method can be used to replace tedious and time-consuming methods.

The Raman spectrum of the organophosphorus pesticide fenthion is presented, and a novel Fourier transform (FT)-Raman method for the quantitative determination of fenthion in pesticide formulations is proposed. Calibration curves based on Raman intensity and band area at 2951, 1065, 661, and 604 cm−1 were linear (correlation coefficients: 0.991–0.998) in the concentration range of 0.4–4.36 M. Detection limits ranged between 0.14 to 0.36 M and precision from 0.4 to 6.8% relative standard deviation (RSD) (n = 4). Spectra normalization against the 802 cm−1 cyclohexane band proved to be effective in minimizing the effect of excitation intensity fluctuations and sample positioning changes in calibration data, resulting in improved long-term stability of the calibration curves. Results obtained during the analysis of the Lebaycid formulation compare well with those obtained by the gas chromatography (GC) reference method. The proposed FT-Raman method is fast, simple, and safe, avoids sample pretreatment, and minimizes handling of toxic samples.

Fourier transform (FT) Raman spectroscopy based on band intensity or band area measurements was used for the quantitative determination of acyclovir in pharmaceutical solid dosage forms through their poly(vinyl chloride) blister package. Univariate calibration using the bands observed at 1690, 1630, 1574, 1482, 1181, 578, and 508 cm(-1) was found to be sufficient for the analysis. Calibration curves were linear, the correlation coefficients being 0.997-0.9993 and 0.996-0.9991 for band intensity and band area measurements, respectively. Results obtained compare well, as indicated by the t-test, with those obtained by the current United States Pharmacopoeia (USP 24) and National Formulary (NF 19) method. Precision ranged from 0.7-4.5 and 0.4-4.0% RSD (n = 3) for band intensity and band area measurements, respectively. The developed nondestructive FT-Raman method is rapid, simple, and can be used for the on-line, real-time monitoring of acyclovir formulation production lines.

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A Fourier transform (FT)-Raman method for the quantitative determination of methyl-parathion in pesticide formulations is described. The proposed method was applied to the analysis of formulations of methyl-parathion. Univariate and multivariate calibration were used and compared for quantitative analysis. Bands observed at 634, 661, 1113, 1348, and 1527 cm−1 were used for univariate calibration. Calibration curves were linear (correlation coefficients: 0.996–0.998 and 0.994–0.999 for band intensity and band area measurements, respectively) in the concentration range of 0.6–3.75 M for the 634, 661, and 1527 cm−1 bands; 0.05–3.75 M for the 1113 cm−1 band; and 0.1–3.75 M for the 1348 cm−1 band. Precision ranged from 0.5 to 5.2% and 0.1 to 6.8% relative standard deviation (RSD) ( n = 4) for band intensity and band area measurements, respectively. Spectra normalization against the 802 cm−1 cyclohexane band improved the long-term stability of calibration, allowing the use of calibration data acquired 30 days prior to analysis. The application of the method was extended through multivariate calibration by multiple linear regression using the 858 and 2952 cm−1 bands. Results obtained compare well with those obtained by the high-performance liquid chromatography (HPLC) reference method. The FT-Raman method developed is rapid, simple, and safe, as toxic samples are analyzed “as received” without sample pretreatment.