By: Mimi Martinez
Identifying the content of medications in waste and at their end-of-life stage is a complex challenge, particularly when it comes to determining their concentration and ensuring their proper disposal or recycling.
Traditional analytical techniques often require complicated processes and specialized equipment, making it difficult to evaluate the environmental impact of pharmaceuticals accurately. Recent advancements[1], however, have shown promise in using innovative methods to estimate the quantities of two commonly used medications—Dexamethasone sodium phosphate (DSP) and Chloramphenicol (CHL)—by utilizing green, blue, and white color scale interactions with light.
These methods, based on ultraviolet (UV) light, have been validated for their effectiveness in analyzing both pure forms and application-ready formulations of the drugs, providing a more sustainable alternative to conventional methods like High-Performance Liquid Chromatography (HPLC). The techniques considered, including derivative ratio, ratio difference, fourier self-deconvolution, induced dual wavelength, and zero-order absorption spectra, have demonstrated eco-friendly benefits when tested with tools like RGB12, AGREE, GAPI, and BAGI. Furthermore, these methods have been rigorously tested against International Council for Harmonisation (ICH) guidelines, addressing critical challenges such as spectral overlap and collinearity, ultimately proving their reliability and robustness.
The zero-order absorption spectra method (D0) is the simplest approach, where the absorbance of CHL is directly measured at 292.0 nanometers, with DSP showing no absorbance, ensuring no interference from the latter. The induced dual wavelength (IDW) method resolves overlapping spectra by selecting two wavelengths on the zero-order spectrum of DSP, where CHL does not contribute to absorbance, allowing for accurate quantification of DSP in the presence of CHL. The fourier self-deconvolution (FSD) method utilizes zero-crossing points in the spectrum to deconvolute the overlapping signals, providing a clear separation of the two drugs and enabling the quantification of DSP at a zero-crossing point of CHL. The ratio difference (RD) method relies on measuring amplitude differences between two specific wavelengths, offering high sensitivity and linearity for DSP when using a known concentration of CHL as the divisor. Lastly, the derivative ratio (DD1) method enhances sensitivity by focusing on the first derivative of the ratio spectra, enabling accurate calibration at the maximum wavelength of DSP while minimizing interference from CHL. These methods, through their unique approaches to overcoming spectral overlap and interference, offer simple, rapid, and eco-friendly solutions for analyzing drug mixtures in a sustainable manner.
The methods from this study mark a significant breakthrough in the field of pharmaceutical analysis, offering a set of innovative and environmentally sustainable methods for the concurrent quantification of Dexamethasone sodium phosphate (DSP) and Chloramphenicol (CHL).
