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Mitoxantrone is a synthetic anthracenedione oncogenic therapy. It is often prescribed as an anticancer agent to manage a variety of cancers. A green, fast, and easy fluorimetric technique for the assay of Mitoxantrone (MXN) as a topoisomerase type II enzyme suppressor. An investigation of MXN's fluorescence behavior in various media and solvents constituted the basis for this new technique. Methanol was shown to enhance the intrinsic fluorescence considerably. After excitation at 610 nm, the highest fluorescence intensity was found at 675 nm. Various experimental parameters, such as media, solvents, and pH levels, were tested and adjusted. ICH guidelines were followed when validating procedures. It was possible to achieve linearity in the 0.02-1.50 μg ml

A new, rapid, highly sensitive, and affordable spectrofluorimetric approach has been constructed and validated for the determination of octreotide in its authentic form and pharmaceutical dosage form. Octreotide is an important synthetic analog of the naturally occurring somatostatin hormone. The developed spectrofluorimetric approach is actually dependent on the measurement of octreotide native fluorescence at emission wavelength of 342 nm after excitation at 218 nm. At optimal reaction conditions, the calibration curve has been constructed over the concentration range 200-2000 ng ml

The present work was performed in order to study the mechanism of micellar thin layer chromatography (MTLC) and to develop a new simple and sensitive simultaneous MTLC method for separation of empagliflozin, Linagliptin and metformin hydrochloride ternary mixture. The study was done using three different surfactants; sodium dodecyl sulphate (SDS), benzalkonium chloride (BAC) and polysorbate 80 (tween 80). Chromatographic procedure was performed using micellar mobile phase that composed of aqueous solution of each surfactant and methanol (6: 4 v/v) and micellar TLC determination at λmax 237 nm. Separation using SDS (anionic surfactant) and BAC (cationic surfactant) depends on ionization potential (AMI-IP), partition coefficient (logP (o/w)) and hydrogen bond donor atoms (a-don), whereas separation using tween 80 depends mainly on the lipophilicity (RM0), solvation energy (E-sol) and Van der Waals energy (E-vdw). Quantitative structure–retention relationships study was carried out, modeled, evaluated and validated using molecular operating environment software.

In the present study, a novel spectrofluorimetric approach was designed for the analysis of captopril as a thiol-containing compound. The approach is based on the formation of a ternary fluorescent compound between the target thiol compound

In this work, a direct, simple, one-pot, and green spectrofluorimetric approach was applied to measure mitoxantrone, a chemotherapeutic agent, through a green validated method. The suggested approach focused on establishing an easy association complex combining mitoxantrone and the eosin Y reagent in a slightly acidic solution. The fluorometric analysis was dependent on off-mitoxantrone action on the emission intensity of the dye (eosin Y) at 544.5 nm (excitation = 301 nm). The devised system has a linear range of 0.07-2.5 μg mL

The present work was developed to create three rapid, simple, eco-friendly, cheap spectrophotometric methods for concurrent assay of Sofosbuvir (SOF) and Simeprevir (SMV) in their pure, laboratory prepared mixture and pharmaceutical dosage form with high degree of accuracy and precision. Three methods were developed including isosbestic point, ratio subtraction and dual wavelength. The linear range of the proposed methods was 3–50 and 2–50 µg mL− 1 for SMV and SOF, respectively. The proposed methods were validated according to ICH guidelines in terms of linearity, accuracy, precision, limit of detection and limit of quantitation. The proposed approach is highly simple and the procedure is environmentally green making it suitable for the drug analysis in routine works.

A high-performance thin-layer chromatographic method was developed and validated for the concurrent determination of simeprevir (SMV) and sofosbuvir (SOF). The chromatographic separation was attained on silica gel 60 F254 as stationary phase and ethyl acetate–hexane–methanol (5.0:4.0:1.0, v/v/v) as developing solvent with UV detection at 273 nm. The RF values were 0.67±0.02 and 0.43±0.02 for SMV and SOF, respectively. The method has been validated in respect to the guidelines of the International Conference on Harmonization. Linearity was maintained between 60–1,000 and 70–1,200 ng/band for SMV and SOF, respectively, with good correlation coefficients (0.9993–0.9997) for both drugs. The suggested method was highly sensitive as the calculated detection limits were 15 and 22 ng/band, while the quantitation limits were 44 and 66 ng/ band for SMV and SOF, respectively. The suggested methodology has been effectively employed for the determination of the mentioned drugs in their pure forms and their pharmaceutical dosage forms as well as human plasma without significant interference of the pharmaceutical excipients or plasma components.

A green spectrofluorimetric method for determining Bilastine (BIL) was described. The method is very sensitive, simple, and quick. The suggested method was depend on the measurement of the original fluorescence of BIL in 1.0 M sulfuric acid at an emission wavelength of 385 nm after an excitation at 272 nm. The method was evaluated by ICH requirements. The relationship between BIL concentrations and the fluorescence intensities was linear in a range of 10.0–500.0 ng mL− 1, and the correlation coefficient was 0.9999. The detection limit was 2.9 ng mL− 1 and quantitation limit was 8.8 ng mL− 1. The suitable sensitivity and selectivity of the suggested method enabled its application successfully in analyzing BIL in real human plasma with appropriate recoveries from 95.72% to 97.2 %, as well as in pharmaceutical preparations without any interfering effect from plasma components or pharmaceutical excipients. Additionally, the suggested method was utilized efficiently for content uniformity test.

In this study, spectrofluorimetric and resonance Rayleigh scattering techniques were applied for the first time for determination of rupatadine through two validated methods. The proposed methods were based on a facile association complex formation between rupatadine and erythrosin B reagent in acidic medium. Spectrofluorimetric determination relied on the quenching effect of rupatadine on the fluorescence intensity of erythrosin B at 556 nm (excitation = 530 nm). Conversely, the resonance Rayleigh scattering (RRS) method relied on enhancement in the resonance Rayleigh scattering spectrum of erythrosin B at 344 nm after the addition of rupatadine. The developed methods produced linear results over ranges 0.15-2.0 μg/ml and 0.1-1.5 μg/ml, with detection limits of 0.030 μg/ml and 0.018 μg/ml for the spectrofluorimetric method and the RRS method, respectively. All reaction conditions for rupatadine-erythrosin B formation were optimized experimentally and both methods were validated according to International Council for Harmonisation guidelines. The developed methods were applied to estimate rupatadine content in its pharmaceutical tablet dosage form with acceptable recoveries. Furthermore, a content uniformity test for the commercial rupatadine tablets was successfully applied by the suggested spectroscopic methods according to United States Pharmacopeia guidelines.

In the current proposed analysis, a new, feasible, and selective fluorimetric approach was designed for baclofen assay. Baclofen is a medication prescribed as a therapy for muscle spasticity that originated from multiple sclerosis or a spinal cord injury, and other cases such as hiccups. The analytical approach relies on the use of ninhydrin to form a fluorescent derivative that was monitored at λex 386 nm or λem 480 nm. Under suitable reaction conditions, the primary amino moiety in baclofen was condensed with ninhydrin and phenylacetaldehyde in the presence of Teorel buffer as a buffered medium. The method exhibited linearity when baclofen concentration was plotted against response in the range 1-10 μg ml-1 . Adjustment of the reaction variables and study of validation parameters according to ICH directives were performed correctly. An interference study was implemented to ensure that no discrepancy from the excipient had occurred. Finally, the proposed method was applied successfully for baclofen assay in dosage form and extended to test Mylobac content uniformity.

Alloxan is a toxic substance that is used as a diabetogenic agent in experimental animals and was found to be toxic to the kidney as well. Alloxan is speculated to be produced during the bleaching process of wheat flour, and there are no confirmations about its presence in the bread or other flour-derived foods. In this study, we intended to explore the presence of alloxan in all-purpose flour, as well as its extension to flour-derived food, by a highly selective, cost-effective, and fully validated spectrofluorometric method. The utilized method is based on the derivatization of alloxan with 1,2-diaminobenzene in acidic medium to produce a flavin fluorescent derivative. The structure of the formed flavin derivative was confirmed by tandem mass spectrometry. The method showed a linear response for alloxan in the range of 0.1–9.0 μg/mL, with a detection limit of 27 ng/mL. In addition, the utilized fluorometric method was found to be eco-friendly when tested with green chemistry metrics. Furthermore, the method was applied successfully for the determination of alloxan in different flour types with good recoveries that ranged from 88.1 to 96.1%. Alloxan concentrations in the bleached flour samples ranged from 0.43 to 0.83 μg/g. However, when the method was applied to flour-based food samples such as spaghetti, noodles, bread, rice, and white sugar, alloxan was not detected in all of them. This might be attributed to the destruction of alloxan during the baking and other preparation processes of these food products.

Objective: A rapid and environmental friendly microemulsion liquid chromatographic method was developed for simultaneous quantification of morphine (MOR), tramadol (TRA) and lornoxicam (LOR) in biological fluids. Methods: Microemulsion used in this study was an aqueous solution containing sodium dodecyl sulfate (0.12 M), n-propanol (10%), ethyl acetate (0.75%), tri-ethyl amine (0.3%), orthophosphoric acid (0.15 %) and the pH was adjusted to 3.0 with orthophosphoric acid. Chromatographic separation was carried out on a monolithic C18 column and a mobile phase flow rate of 1.0 mL min−1 was applied throughout the analysis. The data was monitored using UV-detection mode at a wavelength of 220 nm. Results: Under the optimized conditions, all the studied drugs were well resolved and completely eluted within 6 min. The proposed method was linear over the concentration ranges of 0.5−100, 0.75−125 and 0.25−50 μg mL−1; limits of detection of 0.074, 0.086 and 0.056 μgmL−1 and limits of quantification of 0.21, 0.28 and 0.12 were recorded for TRA, LOR, and MOR, respectively. The developed method was fully validated according to the ICH guidelines. The method was successfully utilized to estimate the tested analytes in plasma and urine samples, which were directly injected into the chromatographic system after suitable dilution with the microemulsion. Conclusion: The developed method is considered to be very efficient to analyze the cited drugs in different biological fluids with low running costs and short analysis time.

A new fluorimetric procedure is described for analysis of milnacipran in its bulk, tablet dosage forms, as well as in biological human samples such as plasma and urine. The suggested method relies on the construction of a derivative with strong fluorescence called dihydropyridine derivative. This derivative resulted from the interaction of the primary amino group in the studied drug and acetylacetone/formaldehyde in McIlvaine buffer (pH 5). The fluorescent dihydropyridine derivative was measured at 470 nm. Influences of experimental variables namely pH, reagent concentration and temperature were examined and optimized. The calibration curve showed linearity over the range of 0.15-1.25 μg ml-1 of milnacipran with an R2 value of 0.9998. The detection limit was 0.02 μg ml-1 and the determination limit was 0.07 μg ml-1 . The developed procedure was successfully used in the assay of the studied drug in Avermilan® tablets with excellent selectivity. In addition, the reaction was applied to estimate the drug in spiked human plasma and urine with mean percentage recoveries of 100.04 ± 1.61 and 99.78 ± 0.81% for urine and plasma, respectively.

Alogliptin is an antidiabetic drug that belongs to a group called dipeptidyl peptidase-4 enzyme inhibitors. As the drug contains a primary amino group in its structure, it readily reacts with fluorescamine in slightly alkaline medium (borate buffer, pH 8.8) to form a highly fluorescent product. Emission of this product was measured at 477 nm (λex = 387 nm). The linear range between the fluorescence intensity and the drug concentration was 0.1-0.5 μg ml-1 with a good correlation coefficient (0.9986). Limits of detection and quantitation were 22 and 72 ng ml-1 , respectively. Guidelines of the International Conference for Harmonisation were followed to validate the developed method with acceptable results. Alogliptin content was determined successfully in its commercial dosage form using the fluorescamine method with good recovery (98.60-101.26%). The method has excellent levels of accuracy and precision compared with the reported method as assessed using Student's t-test and Fisher's exact test. The method was applied successfully for the content uniformity test with high recovery and low relative standard deviation.

The present study developed and validated a selective spectrofluorimetric method designed to assay fluvoxamine maleate (FLX). The validated method relied on the condensation reaction between FLX and acetylacetone/formaldehyde using acetate buffer (pH 4.2). The formed fluorescent product was measured at an emission wavelength of 479 nm after excitation at 419 nm. Parameters that influenced the reaction were studied and adjusted accurately. The constructed calibration graph was rectilinear over the range 200-2000 ng ml-1 and the estimated limit of detection was 60 ng ml-1 . Two products from an Egyptian market were assayed using the suggested method and the final results agreed with the measurements of the reported method. The selectivity of the proposed approach was evaluated using the standard addition method and results were acceptable and confirmed the reliability of this approach. Finally, directives from the International Council for Harmonisation guidelines were applied to establish the validity of the study.

Citicoline and piracetam were subjected separately to different stress conditions as recommended by the international conference on harmonization. In addition, new stability indicating thin layer chromatographic and ultra high performance liquid chromatographic methods have been developed and validated for simultaneous determination of citicoline and piracetam in presence of their degradation products. Separation on the proposed thin layer chromatographic method was carried out using a developing system containing methanol:chloroform:ammonium chloride buffer (9:1:2, v/v/v) on silica gel plates at 230 nm. On the other hand, the mobile phase in the ultra high performance liquid chromatographic method was composed of water (containing 0.1% triethylamine):ethanol (92:8, v/v). The flow rate was 1 mL/min and ultraviolet detection was at 230 nm. Moreover, results of the developed methods were statistically compared to those obtained by the reported high-performance liquid chromatography method and no significant difference between them was found. The greenness profile of ultra high performance liquid chromatographic method was assessed and compared with those of the previously published high-performance liquid chromatography methods, it was noticed that the proposed ultra high performance liquid chromatographic method more environmentally friendly and greener than other methods.

Simeprevir (SPV) is a powerful antihepatitis C virus agent that was newly introduced into the pharmaceutical market. We here established and validated an easy, simple, and sensitive spectrofluorimetric method for its estimation at λem 427 nm (λex 337 nm). The suggested procedure was based on two times enhancement in the original emission of SPV through modifying its microenvironment in buffered aqueous solution by adding Triton X-100. The relationship between the concentration of SPV and the observed fluorescence intensity was linear in the range 0.06-1.0 μg ml-1 with a correlation coefficient of 0.9997. The limits of detection and quantitation were 21 and 64 ng ml-1 , respectively. The present method was effectively applied to quantify SPV content in pharmaceutical tablets and human plasma spiked with the drug with no interference from tablet excipients or plasma components.

A validated thin-layer chromatography (TLC) method combined with fluorescence detection mode was developed for the selective determination of a recently approved anti-hepatitis C virus (HCV) drug (velpatasvir). The separation was performed on silica gel 60 F254 plates using ethylacetate:methanol:triethylamine (48:1.5:1.0, v/v/v) as a mobile phase. Plates were scanned in the fluorescence mode after excitation at 335 nm. This method provided an excellent separation of velpatasvir from sofosbuvir with RF values of 0.22 and 0.46 for velpatasvir and sofosbuvir, respectively, after scanning the developed plates in the ultraviolet detection mode at 335 nm. The calibration curve was linear over the range 4-40 ng/band with a correlation coefficient of 0.9994. The developed procedure was validated according to ICH guidelines with a detection limit of 1.30 ng/band and quantitation limit of 3.95 ng/band. The suggested method could selectively determine velpatasvir with high sensitivity in a synthetic tablet powder containing a co-formulated anti-HCV drug (sofosbuvir) without any interference from excipients or sofosbuvir. In addition, the method was successfully applied for determination of velpatasvir in spiked human plasma with adequate % recovery.

The present study describes the validation of a selective spectroscopic method for assay of fluvoxamine maleate (FXM). The validated method relies on condensation of FXM with 2,2-dihydroxyindane-1,3-dione and phenylacetaldehyde using Teorell-Stenhagen buffer (pH 6.6) to give coloured fluorescent product measured at 482 nm using 386 nm as the excitation wavelength. The parameters influencing the reaction were studied precisely and adjusted accurately. The constructed calibration graph appeared rectilinear over the following range (0.8-14 μg ml-1 ) and the estimated limit of detection was 0.25 μg ml-1 . Two pharmaceutical products from the Egyptian market were assayed using the suggested method and the final results agreed with measurements from other reported methods. Moreover, the drug was subjected to diverse stress conditions including acidic, alkaline, thermal, and photolytic degradation to examine the FXM stability. Directives from the International Conference on Harmonisation guidelines were applied to establish the validity of the work.

Cefotaxime was selectively determined using a sensor based on polymeric membrane electrode. The membrane incorporated a low-cost and commercially available anion exchanger namely tridodecyl methyl ammonium bromide (TDMAB), embedded in a plasticized PVC matrix. The influence of the composition of the membrane (e.g., type and amount of ion exchanger, besides the plasticizer type) on potentiometric behavior of the synthesized membrane electrode was investigated. The optimized membrane electrode showed near-Nernstian response towards cefotaxime with slope of −53.65 mV decade−1. The linear concentration range for the quantitation of cefotaxime sodium was 0.17 – 10 mM. The calculated detection limit was 0.12 mM. The prepared TDMAB based membrane was incorporated in a tubular-type sensor. The sensor was adopted for continuous cefotaxime determination under hydrodynamic mode. The tubular-type sensor showed a near-Nernstian response (−52.90 mV decade−1) in a range of concentrations of 0.5 – 10 mM. The selectivity studies demonstrated that the optimized membrane electrode displayed high selectivity for cefotaxime over several members of anions and other cephalosporin drugs such as; cefaclor, cefadroxil, cefoperazone, cefradine and ceftazidime. The analytical utility of suggested membrane sensor was demonstrated by cefotaxime quantification in different pharmaceutical formulations using both the direct potentiometric and flow-injection methods. The calculated results were in accordance to those obtained using the reported UV–visible method in respect to precision and accuracy.

A novel selective and highly sensitive TLC densitometric method with reflectance/fluorescence detection was developed to separate and quantify montlukast (MONT) and loratadine (LOR). Separation of the studied drugs was performed on precoated silica gel TLC plates using chloroform-ethyl acetate (8 :2 v/v) as a mobile phase. MONT quantification was carried out by measuring emission using 400 nm optical filter after excitation at 340 nm. Enhancement of the week LOR fluorescence was performed through adequate spraying the chromatograms with 0.2 M perchloric acid leading to enhancing sensitivity by 17 folds compared to the reported HPTLC methods with absorbance detection. The scanner was set at 275 nm excitation wavelength and 400 nm optical filter. Detection of both drugs on the same plate separately at different pH conditions was utilized for the first time. Maximum fluorescence was achieved for each of them and this enhances detection sensitivity for both drugs. The linear regression analysis data of the studied drugs produced a good linear relationship with correlation coefficients of 0.996 for MONT and 0.998 for LOR over the concentration range of 6 - 150 ng/band for MONT and 15 - 120 ng/band for LOR. Limit of detection values were 1.7 and 4.5 ng /band for MONT and LOR respectively. The developed method enabled the detection of MONT and LOR in human plasma samples within linear concentrations ranged from 7 to 140 ng/ band and 16 to 50 ng/ band with detection limits of 1.9 and 4.8 ng/band for MONT and LOR respectively. The analytical performance of the proposed method was evaluated according to the International Council for Harmonization (ICH). The method was successfully applied for the analysis of the studied drugs in spiked human plasma and good recovery percentages were obtained indicating that there is no interference from plasma constituents. Therefore the method can be applied for in vivo analysis and pharmacokinetic study.

The antihypotensive drug heptaminol was determined using a spectrofluorimetric method and ortho-phthaladehyde as a fluorescence probe. The drug was mixed with the reagent in the presence of 2-mercaptoethanol and the reaction was carried out in slightly alkaline aqueous solution containing 0.1 M sodium hydroxide. The resulting product exhibited high fluorescence activity that was measured at 451 nm after excitation at 334 nm. The linearity range of the method was 5-100 ng ml-1 with a lower detection limit of 1.8 ng ml-1 . The procedure was evaluated according to the International Council of Harmonization guidelines. The proposed method was applied to analyze the drug in pharmaceutical tablets and oral drops. In addition, the present study represents the first spectrofluorimetric method for the determination of the cited drug in real human plasma. The method provided high recovery percentages without any interference from coexisting pharmaceutical excipients or the components of human plasma.

A simple, sensitive, low-cost, quick and reliable square-wave anodic stripping voltammetric method is described for the determination of the antidiabetic drug Linagliptin (LNG) in pure form, tablets, and spiked human urine and plasma samples. Using a pencil graphite electrode (PGE), cyclic voltammetry (CV) was applied to study the electrochemical behavior of LNG. In a Teorell-Stenhagen buffer (pH 5.5) containing 0.1 M NaClO4 as a supporting electrolyte, the LNG yields an irreversible well-defined oxidation peak at about 1.2 V vs. Ag/AgCl electrode. The various affecting factors, such as the pH, buffer type, supporting electrolyte, accumulation potential, scan rate and accumulation time, were tested and optimized. Also, square-wave adsorptive anodic stripping voltammetric (SWAdASV) studies show that the peak current various linearly over the LNG concentration range of 0.24 - 5.20 μg mL-1 (R2 = 0.9994). The detection and quantification limits were calculated to be 0.10 and 0.33 μg mL-1, respectively. The proposed procedure exhibits a good precision, selectivity, and stability and was applied successfully to determine the LNG in pharmaceutical formulations (tablets) and biological fluids (spiked human urine and plasma samples).

Herein, a sensitive and reliable eco-friendly TLC-spectrodensitometric method has been established for the simultaneous determination of dapagliflozin (DAPA) and rosuvastatin (ROSV) for the first time. TLC separation was carried out on silica gel F254 using ethyl acetate : methanol (5 : 0.1, v/v) as a mobile phase and UV measurement at 243 nm. The method was fully validated according to ICH guidelines. Acceptable separation was achieved with Rf values of 0.23 and 0.44 for DAPA and ROSV, respectively. Regression plots revealed linear relationships in the concentration range 20–2500 ng per band and 10–2500 ng per band with LODs of 6.60 and 3.57 ng per band for both DAPA and ROSV, respectively. The relative standard deviations (RSDs%) were found to be 1.35 and 0.53 for DAPA and ROSV, respectively. Moreover, kinetic studies were conducted for measurement of degradation rate constant (k) and half life time (t1/2) of DAPA and ROSV via forced photo-degradation.

In this work, a resonance Rayleigh scattering technique and a spectrofluorimetric technique were applied to the quantification of cyclobenzaprine through two validated methods. The suggested methods are based on a facile association complex formation between cyclobenzaprine and eosin Y reagent in the acidic medium. The resonance Rayleigh scattering method relied on the enhancement in the resonance Rayleigh scattering spectrum of eosin Y at 370 nm after the addition of cyclobenzaprine. On the other hand, the spectrofluorimetric quantification relied on the quenching effect of cyclobenzaprine on the fluorescence strength of the eosin Y reagent at 545 nm (excitation wavelength at 300 nm). The suggested methods were linear over the ranges of 0.07–1.75 μg/mL and 0.15–2.0 μg/mL with detection limit values of 0.023 μg/mL and 0.048 μg/mL for the resonance Rayleigh scattering method and the spectrofluorimetric method, respectively. All reaction conditions for cyclobenzaprine–eosin Y formation were experimentally evaluated and optimized. In addition, both methods were validated based on ICH rules. Furthermore, the developed methods were practically applied to the analysis of cyclobenzaprine in its commercial tablet dosage form with acceptable recoveries. Moreover, the content uniformity test of the commercial cyclobenzaprine tablets was successfully applied using the proposed spectroscopic methods based on USP rules.

Helicobacter pylori (H. pylori) infection is common and can result in gastric and duodenal ulcers, and in some cases, gastric lymphoma and cancer. Omeprazole (OMP)-in combination with clarithromycin (CLR), amoxicillin (AMX), tinidazole (TND), or metronidazole (MET)-is used in double or triple combination therapy for eradication of H. pylori. However, the roles of the drugs other than OMP are not clearly understood. Therefore, in the present study, we aimed to investigate any effects of these drugs on OMP metabolism by wild-type CYP2C19 using spectroscopy and enzyme kinetics. The dissociation constants (Kd) for CYP2C19 with OMP, CLR, AMX, TND, and MET were 8.6, 126, 156, 174, and 249 µM, respectively. The intrinsic clearance of OMP was determined to be 355 mL/min/µmol of CYP2C19. Metabolism of OMP was significantly inhibited by 69, 66, 28, and 40% in the presence of CLR, TND, AMX, and MET, respectively. Moreover, the combination of CLR and TND resulted in 76% inhibition of OMP metabolism, while the combination of AMX and MET resulted in 48% inhibition of OMP metabolism. Both combinations of drugs not only have antibacterial effects, but also enhance the effect of OMP by inhibiting its metabolism by CYP2C19. These results indicate that drug-drug interactions of co-administered drugs can cause complex effects, providing a basis for OMP dose adjustment when used in combination therapy for H. pylori eradication.

Linagliptin (LNG) is a type 2 antidiabetic drug which belongs to dipeptidyl peptidase 4 inhibitors. In this paper a simple and sensitive spectrofluorometric method was developed and validated for the determination of LNG. The method employed the interaction of the primary amino group of the cited drug with fluorescamine reagent in aqueous borate buffer (pH 8.5) to produce a highly fluorescent product. The emission of the formed product was measured at 479 nm after excitation at 390 nm. Different experimental parameters that may affect the product formation or its fluorescence intensity were investigated and adjusted. The method has a good linearity in the concentration range of 0.2 – 2.0 μg mL−1of LNG with a detection limit of 0.079 μg mL−1.The performance of the developed method was evaluated according to the International Conference for Harmonization (ICH). The method was successfully applied for the analysis of tablets dosage form that contained the cited drug. The results of the analysis were compared with the reported method and indicated good accuracy and precision of the proposed procedure.

Recently approved anti-HCV drugs are a breakthrough new medication for the treatment of all genotypes hepatitis C virus infection. A selective, non-destructive and precise fourier transform infrared (FTIR) spectroscopic method was established and validated for the direct determination of daclatasvir dihydrochloride (DAC) and sofosbuvir (SOF) in pharmaceutical dosage forms. The method based on measurement the stretching bands of carbonyl group spectral range from 1695 to 1740 cm−1 for the studied drugs. The suggested procedures were completely validated through ICH guidelines with linear ranges of 0.25 −20.0 and 0.5 −20.0 mg g−1 for DAC and SOF, respectively. The values of LOQ were 0.149 and 0.172 and the values of LOD were 0.049 and 0.057 mg g−1 for DAC and SOF, respectively. Also, the analytical procedure was developed in agreement with green chemistry and the obtained results are found to be in a good agreement with that of the destructive methods. Moreover, the method was successfully applied for the direct and rapid supervision the uniformity of dosage units for the studied anti-HCV drugs in their pharmaceutical tablets dosage form.

A simple colorimetric method for the quantitative detection of two cephalosporins, cefoperazone (CFZ) and cefepime (CPM), has been developed and validated for the application in clinical and quality control laboratories. The method was based on exploiting the reducing properties of cephalosporins due to the 7-aminocephalosporanic acid dihydrothiazine and a β-lactam ring to produce gold (GNPs) or silver (AgNPs) nanoparticles from their corresponding metal solutions. The resulting nanoparticles exhibited surface plasmon resonance signals at 530–550 nm or 430 nm for GNPs or AgNPs, respectively, with an intensity dependent on drug concentration that permits the quantitative analysis. Furthermore, the resulting nanoparticles were characterised using a dynamic light scattering instrument and transmission electron microscopy. Factors influence the reaction, such as the reagents volume, pH, temperature and reaction time, have been studied and optimised. In addition, the study was validated according to the official guidelines and extended to evaluate the antimicrobial activity to assess potential drug degradation during the analysis. Overall, the method developed in this study can be used for the quantitative analysis of CFZ and CPM in pure forms and pharmaceutical preparations with relatively good sensitivity and selectivity as well as, acceptable accuracy and precision.