Abstract:
The presence of minor components represents a challenging problem in spectrophotometric analysis of pharmaceuticals. If one component has a low absorptivity or present in a low concentration compared to the other components, this will hinder its quantitation by spectrophotometric methods. Continuous Wavelet Transform (CWT) as a signal processing technique was utilized to figure out a solution to such a problem. A comparative study was established between traditional derivative spectrophotometry (Numerical Differentiation, ND) and CWT to indicate the advantages and limitations of each technique and possibility of solving the problem of minor components. A mixture of ibuprofen (IBU) and phenylephrine (PHE) with its degradation products forming a ternary mixture was used for comparing the two techniques. The two techniques were applied on raw spectral data and on ratio spectra data resulting in four methods, namely ND, CWT, Derivative Ratio-Zero Crossing (DRZC) and Continuous Wavelet Transform Ratio-Zero Crossing (CWTR-ZC) methods. By comparing the results in laboratory prepared mixtures, CWT technique showed advantages in analysis of mixtures with minor components than ND. The proposed methods were validated according to the ICH guideline Q2(R1), where their linearity was established with correlation coefficient ranging from 0.9995 to 0.9999. The linearity was in the range 3-40 μg/mL for PHE in all methods, while for IBU it was 20-180 and 30-180 μg/mL in CWT and ND methods, respectively. The CWT methods were applied for quantitative determination of the drugs in their dosage form showing the ability of the methods to quantitate minor components in pharmaceutical formulations.
摘要:
次要组分的存在代表了药物的分光光度分析中的挑战性问题。如果一种成分与其他成分相比吸收率低或浓度低,这将阻碍其通过分光光度法进行定量。连续小波变换(CWT)作为一种信号处理技术,用于解决此类问题。建立了传统导数分光光度法(数值微分,ND)和CWT,以表明每种技术的优点和局限性以及解决次要成分问题的可能性。布洛芬(IBU)和去氧肾上腺素(PHE)的混合物及其降解产物形成三元混合物,用于比较两种技术。这两种技术应用于原始光谱数据和比率光谱数据,得到四种方法,即ND,CWT,导数比率零交叉(DRZC)和连续小波变换比率零交叉(CWTR-ZC)方法。通过比较实验室制备混合物的结果,CWT技术在分析比ND次要成分的混合物方面显示出优势。根据ICH指南Q2(R1)对所提出的方法进行了验证,其中它们的线性被建立,相关系数在0.9995到0.9999之间。在所有方法中,PHE的线性范围为3-40μg/mL,而对于IBU,CWT和ND方法为20-180和30-180μg/mL,分别。CWT方法用于定量测定其剂型中的药物,显示该方法对药物制剂中的次要组分进行定量的能力。