692 Mowaka et al.: Journal of aoaC InternatIonal Vol. 100, no. 3, 2017 Novel Pure Component Contribution Algorithm (PCCA) and UHPLC Methods for Separation and Quantiication of Amlodipine, Valsartan, and Hydrochlorothiazide in Ternary Mixture Shereen Mowaka British University in Egypt, Faculty of Pharmacy, Pharmaceutical Chemistry Department, 11837 El-Sherouk City, Egypt; Helwan University, Faculty of Pharmacy, Analytical Chemistry Department, Ein Helwan, 11795 Cairo, Egypt Maha a. hegazy Cairo University, Faculty of Pharmacy, Analytical Chemistry Department, Kasr El-Aini St, 11562 Cairo, Egypt hayaM M. Lotfy Cairo University, Faculty of Pharmacy, Analytical Chemistry Department, Kasr El-Aini St, 11562 Cairo, Egypt; Future University, Faculty of Pharmaceutical Science & Pharmaceutical Industries, Pharmaceutical Chemistry Department, 12311 Cairo, Egypt ekraM h. MohaMed 1 British University in Egypt, Faculty of Pharmacy, Pharmaceutical Chemistry Department, 11837 El-Sherouk City, Egypt Two accurate and sensitive methods were developed and validated for the simultaneous determination of amlodipine (AML), valsartan (VAL), and hydrochlorothiazide (HCT) in their ternary mixture. The irst method is a novel simple algorithm capable of extracting the contribution of each component from a mixture signal in which the components are partially or completely overlapped. It is based on the use of a coded function that eliminates the signal of interfering components using mean centering as a processing tool. Determination was performed at 237.6, 250.0, and 270.6 nm for AML, VAL, and HCT, respectively. Two it values were developed and calculated for optimization of the method for each drug, one to test that the absorptivity values of the extracted spectra are within the conidence limits of the slope, and the other for correlation between the pure and extracted spectra. The it values for AML, VAL, and HCT were α = 0.0449, 0.03981, and 0.07251, respectively, and r = 1 for each drug. The second method is an ultra-HPLC (UHPLC ® ) method in which separation of AML, VAL, and HCT was carried out on a UHPLC C 18 column (100 × 2.1 mm, 2.2 µm) using a mobile phase of acetonitrile–methanol–phosphate buffer (pH 2.8; 25 + 50 + 25, v/v/v). The low rate was 0.5 mL/min, and the detection was set at 255.0 nm. The proposed methods were successfully applied to the analysis of AML, VAL, and HCT in pharmaceutical formulations, without interference from the dosage- form additives. The results were statistically compared to a previously reported method, and no signiicant difference was found regarding accuracy or precision. A mlodipine (AML), 2-[(2-aminoethoxy)methyl]-4- (2-chlorophenyl)-1,4-dihydro-6-methyl- 3,5-pyridine carboxylic acid 3-ethyl 5-methyl ester (1), is a vasodilator that belongs to a class of drugs known as calcium channel blockers (CCBs) or calcium antagonists. CCBs also decrease the excitability of heart muscle and, therefore, relieve chest pain (angina) and control irregular heartbeats and abnormal rapid heart rhythms (2, 3). Valsartan (VAL), N-(1-oxopentyl)-N-{[2'-(1H-tetrazol- 5-yl)(1,1'-biphenyl)-4-yl]methyl}-l-valine (4), is a speciic angiotensin II receptor blocker acting selectively on the AT1 receptor subtype (3). VAL slows the worsening and development of end-stage renal disease in people with type II diabetes and high blood pressure or albumin in the urine (5). Hydrochlorothiazide (HCT), 6-chloro-3,4-dihydro-2H-1,2, 4-benzothiadiazine-7-sulfonamide 1,1-dioxide (1), is a thiazide diuretic (6) that reduces blood volume by acting on the kidneys to reduce sodium (Na + ) reabsorption in the distal convoluted tubule. Thiazides increase the reabsorption of calcium in this segment in a manner unrelated to sodium transport. In addition, by other mechanisms, HCT is believed to lower peripheral vascular resistance (7). Recently, some analytical methods were reported for the estimation of the ternary mixture of AML, VAL, and HCT, including UV spectroscopic (8–11), chemometric (11, 12), and chromatographic methods (13, 14). The structures of the drugs are shown in Figure 1. The aim of this work was to use the simple and novel algorithm called pure component contribution algorithm (PCCA), which has no limitations for its application, to achieve resolution and extraction of pure components from their mixture signal without any requirements such as spectral extension or derivative calculations. Moreover, this work aimed to develop a fast (less than 5 min), sensitive ultra-HPLC (UHPLC ® ) method for the simultaneous determination of AML, VAL, and HCT in bulk and in pharmaceutical dosage forms, without the need for prior separation or multiple mathematical calculations. DRUG FORMULATIONS AND CLINICAL METHODS Received July 28, 2016. Accepted by JB October 17, 2016. 1 Corresponding author’s e-mail: ekram.hany@bue.edu.eg DOI: 10.5740/jaoacint.16-0195 00692-00699.indd 692 07/04/17 4:38 pm