Determination of ranitidine, nizatidine, and cimetidine by a sensitive fluorescent probe

Abstract

A validated, simple, and sensitive fluorescence quenching method for the determination of ranitidine, nizatidine, and cimetidine in tablets and biological fluids is presented. This is the first single fluorescence method reported for the analysis of all three H(2) antagonists. The competitive reaction between the investigated drug and the palmatine probe for the occupancy of the cucurbit[7]uril (CB[7]) cavity was studied using spectrofluorometry. CB[7] was found to react with the probe to form a stable complex. The fluorescence intensity of the complex was also enhanced greatly. However, the addition of the drug dramatically quenched the fluorescence intensity of the complex. Accordingly, a new fluorescence quenching method for the determination of the studied drugs was established. The different experimental parameters affecting the fluorescence quenching intensity were studied carefully. At optimum reaction conditions, the rectilinear calibration graphs between the fluorescence quenching values (ΔF) and the medicament concentration were obtained in the concentration range of 0.04-1.9 μg mL(-1) for the investigated drugs. The limits of detection ranged from 0.013 to 0.030 μg mL(-1) at 495 nm using an excitation wavelength of 343 nm. The proposed method can be used for the determination of the three H(2) antagonists in raw materials, dosage forms and biological fluids.

HPLC fluorescence method for the determination of nizatidine in human plasma and its application to pharmacokinetic study

“…The reagent is inexpensive and widely available. The proposed method proved to be simpler, easier and less timeconsuming than previously reported methods (19,(23)(24)(25). Distinct advantages of the current method include the simplicity and rapidity of sample preparation and fluorescence spectra, good sensitivity and the requirement for only common instruments.…”

“…Several analytical methods have been published for the quantification of biological fluids: a voltammetric method for the determination of NIZ in human plasma and urine (18); several high-performance liquid chromatographic (HPLC) methods; an HPLC method with ultraviolet detection (19)(20)(21)(22)(23)(24); and a fluorimetric method (25).…”

Spectroscopy studies of sandwich-type complex of silver(I) co-ordinated to nuclear fast red and adenine and its analytical applications

“…Fluorescence spectrophotometry possesses the advantages of sensitivity and simplicity, hence it has been extensively used in the determination of metal ions , drugs (Feng et al, 2009;Chang et al, 2011), organics (Feng & Liu, 2008) and bioactive materials (Rodríguez Cáceres et al, 2008). However, the determination of adenine in real samples by fluorescence spectrophotometry has hardly been reported.…”

Reversible Shape‐Morphing and Fluorescence‐Switching in Supramolecular Nanomaterials Consisting of Amphiphilic Cyanostilbene and Cucurbit[7]uril

“…Therefore, on the basis of the complementary characteristics of 1 exhibitinge xcellent hydrophobic self-assembling propensity and 2 showing high hydrophilicity,w ed esigned in this work an ew cyanostilbene-based amphiphilic molecule, which is (Z)-4-(4-(2-(3',5'-bis(trifluoromethyl)-[1,1'-biphenyl]-4-yl)-1-cyanovinyl)phenyl)-1-methylpyridin-1-iumc hloride (nameda sc yanostilbene 3,S cheme 1a)f or aw ell-structured amphiphilic nanomaterial with bright luminescencei np ure water.I na ddition, to endow cyanostilbene 3 with shape-morphing and fluorescence-switching abilities throughh ost-guesti nteraction (Scheme 1b), [26][27][28][29][30][31] we decided to employ cucurbit [7]uril(CB [7],Scheme 1a)asapartner molecule of cyanostilbene 3.D ue to significant water-solubility and non-toxicity of the CB [7] compared to other macrocyclic hosts, [31][32][33][34] we expected using CB [7] as the partner molecule of cyanostilbene 3 is the best way to achieve the biosensing nanomaterials in pure water.B riefly,w ea ppliedt his shapemorphing nanomaterial consisting of cyanostilbene 3 and CB [7] to af luorescence" turn-on" biological sensort hrough a dynamic competitive guest exchange reaction. Because biological fluorescence sensors based on the dynamic competitive guest exchanger eactionu sing CB [7] in aqueouss olution are commonly "turn-off" sensors exploiting the fluorescence quenching phenomenon, [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] materializing fluorescence" turnon" biological sensorinthis work is to be noted as asignificant progress as well.…”