A simple innovative spectrofluorometric method for the determination of alendronate in bulk and in pharmaceutical tablets

Abstract

Sodium alendronate is the first in a pharmacological class known as bisphosphonates, used for treatment of various bone diseases. Assay of bisphosphonates by a spectroscopic technique is very challenging due to the fact that they lack chromophores and none of them are fluorescent. In this work, a simple method is presented for determination of alendronate in bulk and in pharmaceutical tablets using spectrofluorometry by exploiting the ability of alendronate to displace salicylate from the iron(III)–salicylate chelate, forming a non‐fluorescent colorless iron(III)–alendronate complex. The liberated salicylate is fluorescent and is equivalent to the mount of alendronate added. The response was linear over the concentration range 20–90 μM and the proposed method was validated according to the guidelines of the International Conference on Harmonization. The correlation coefficient was found to be 0.995 and the limit of detection was 7.5 μM. The method was successfully applied for determination of alendronate in the commercially available Osteonate® tablets. The average percent recovery ± percent relative standard deviation was found to be 102.118 ± 2.033 which is congruent with the label claim of the dosage form. The results were also compared to a reported method using t‐test and F‐test at 95% confidence level; no significant differences were observed. The presented method is simple, fast, easy, cost‐effective and suitable for routine pharmaceutical analysis.

Tuning Ligand Density To Optimize Pharmacokinetics of Targeted Nanoparticles for Dual Protection against Tumor-Induced Bone Destruction

“…The primary amine-containing Aln was then grafted via the amine-reactive PFPA intermediate to create BTNPs with a target of 0, 2, 5, 10, and 100% Aln in the NP surface-forming polymer block. The concentration of Aln was spectrophotometrically quantified on each BTNP by adapting cation-chelation competition assays that exploit the strong and specific binding of the o -cresolphthalein complexone with Ca 2+ . − The experimental DP of Aln was found to be within two units of the theoretical DP for the 0–10% Aln polymer series (Figure B and Table S1). Fourier transform infrared (FTIR) spectra of the BTNP polymers show a stretching vibration from the P–O bond in Aln at ∼910 cm –1 , and an increase in peak intensity with increasing Aln content in polymers indicating Aln content correlated with PFPA content in the parent polymer prior to grafting (Figure C and Figure S1E).…”

“…A fully water-soluble cation-chelation assay adapted from previously established methods was developed in order to measure the polymer-bound Aln relying on the competitive chelation of Ca 2+ with the well-established calcium quantification chromagen, o -cresolphthalein complexone. − First, 10.3 mg of o -cresolphthalein complexone was dissolved into 100 mL of 0.1 M glycine buffer (pH 10) and was used to dissolve various concentration of Aln (standard curve, 0–2 mM) or Aln-containing polymers. Two hundred microliters of each was added to a well of a 96-well plate, and an absorbance reading was measured at 570 nm.…”

A highly sensitive switch-on spectrofluorometric method for determination of ascorbic acid using a selective eco-friendly approach

“…The optimization was performed to achieve the maximum difference (ΔF 411nm ) in the presence of ASC in order to attain the maximum possible sensitivity. In a previous work, different salts of iron (III) were tried with sodium salicylate [27] : iron (III) chloride, iron (III) nitrate and ammonium iron (III) sulfate. The maximum quenching effect and the highest repeatability were obtained when ammonium iron (III) sulfate was used, so that iron (III) salicylate complex was prepared using iron (III) ammonium sulfate and sodium salicylate.…”

“…A concentration of 20 mM ammonium iron (III) sulfate was prepared by weighing 0.964 g, which is then completed to 100 mL using 0.5 mM nitric acid solution. The role of nitric acid as a diluent is to increase the stability of iron (III) salicylate complex [26] , [27] . Iron (III) salicylate in a concentration of 10 mM was prepared by mixing equal volumes of each of the previously prepared solutions, then the former solution was diluted with water to prepare a working solution containing 1 mM iron (III) salicylate.…”

Analytical methods for determination of glutathione and glutathione disulfide in pharmaceuticals and biological fluids

“…Metal-ligand complexes have gained a great interest in the field of biosensing. Transition heavy metal complexes possess particular useful properties that makes them attractive in sensing applications (Taha et al, 2017;Elmalla & Mansour, 2019;Mabrouk et al 2019a;2019b). For example, they have a long lifetime that allows their emission to be distinguished by fluorescent media using time-resolved luminescence spectroscopy (Terpetschnig et al, 1995).…”