A New stability indicating RP-HPLC method for the estimation of Gefitinib tablets using an ion pairing agent

Gefitinib is an anticancer drug used for the treatment of lung cancer, breast cancer and prostate cancer. A new stability indicating RP-HPLC method was proposed for the estimation of Gefitinib in pharmaceutical dosage forms (tablets). Shimadzu Model CBM-20A/20 Alite HPLC system with PDA detector and Agilent C18 column were used for the chromatographic study. Mobile phase mixture consisting of Tetra butyl ammonium hydrogen sulphate and Methanol in the ratio 50:50, v/v with a flow rate 0.8 mL/min was chosen for the chromatographic elution of Gefitinib (Detection wavelength 340 nm). The method was linear over the concentration range 0.1-80 mg/mL with linear regression equation, y = 70782x + 6171.6 (R² = 0.9999). The LOD and LOQ were found to be 0.2931 mg/mL and 0.8947 mg/mL respectively. Stress degradation studies were performed by exposing Gefitinib to various stress conditions and the method was validated as per ICH guidelines.

Analysis of carbohydrates content in the plant components of antidiabetic herbal mixture by GC-MS

Medicinal plants and their combinations due to the wide range of biologically active substances can influence on various links of the pathogenetic mechanism of development of diabetes mellitus and its complications. One of such combinations is an antidiabetic herbal mixture (Urticae folia, Rosae frucrus, Myrtilli folia, Menthae folia and Taraxaci radices) with established hypoglycemic, hypolipidemic, antioxidant, hepatoprotective, pancreatoprotective activity in previous pharmacological study in vivo. Thus, the aim of this study was to identify and establish the content of carbohydrates in free and bound form in the plant components of antidiabetic herbal mixture. The carbohydrates were separated by gas chromatography-mass spectrometry after conversion into volatile derivatives as aldononitrile acetate. The monomeric composition of polysaccharides was studied after their hydrolysis to form monosaccharides and polyalcohols. The results of the quantitative study showed that the predominant carbohydrate in free form was saccharose in Urticae folia, L-fructose in Myrtilli folia, Rosae frucrus, Taraxaci radices and Menthae folia, L-glucose in Rosae frucrus. Concerning the determination of monomers of polysaccharides after hydrolysis, L-glucose prevailed in all plant components of antidiabetic herbal mixture. The chromatographic study revealed a number of polyalcohols that are important for the treatment and prevention of progression of diabetes mellitus and its complications, namely, mannitol and myo-inositol.

Assessing the homogeneity of Actimask® acetaminophen and N-acetyl glucosamine mixture to predict further steps in the development of orodispersible tablets

One of the main problems in the production of tablets, which has significant negative consequences, is the segregation of the tablet mixture leading to inhomogeneity of dosage units, material losses in the manufacturing process and improperness of the specified pharmaceutical technical characteristics of the mixture. The aim of the research. This work aims at the pharmaceutical technical study of the substances N-acetyl-D-glucosamine and Actimask® Acetaminophen and determination the uniformity of the powder mixture of active pharmaceutical ingredients (APIs) to predict the optimal technology for obtaining a pharmaceutical formulation with the acceptable properties. Materials and methods. N-acetyl-D-glucosamine (Zhejiang Candorly Pharmaceutical, China) and Actimask® Acetaminophen (SpiPharma, USA) were used. Scanning probe microscope Solver P47N-PRO ("NT-MDT", Russia), optical microscope, flowability tester VP-12A, laser diffraction particle size analyzer SALD-2201 ("Shimadzu", Japan), liquid chromatograph Agilent 1260 Infinity II with Diode Array Detector (Agilent Technologies, USA), spectrophotometers Shimadzu UV-1800 ("Shimadzu", Japan) were used. The study of API pharmaceutical technical properties (microscopic characteristics, moisture absorption capacity, flowability, bulk volume and tapped volume, particle size distribution by sieve analysis and laser diffraction), as well as vibration simulation and following chromatographic study were carried out in this work. Results and discussion. The shape of the particles N-acetyl-D-glucosamine and Actimask® Acetaminophen, which was determined by microscopic analysis, demonstrated the possibility of N-acetyl-D-glucosamine particles to stick to Actimask® Acetaminophen ones. The experimental study allowed to reveal the hygroscopicity of both APIs; poor flowability, unsatisfactory Hausner ratio, and Carr index for N-acetyl-D-glucosamine; excellent flowability, Hausner ratio, and Carr index for Actimask®. Vibration caused segregation of the powder mixture. It was found that all layers do not meet the requirements and an excessive content of Actimask® is registered, which indicates the stratification of the powder mixture. Conclusions. The physical properties of the substances were determined and found to have significant differences in their particle size distribution. Segregation of the mixture after vibration was confirmed by laser diffraction and assay analysis. In order to solve the segregation problem, the granulation of N-acetyl-D-glucosamine may be proposed.

Synthesis, Spectral, Bio Assay, Chromatographic - Studying of New Imidazole Reagents Via Three Components Reaction

Imidazoles are part of the theophylline Reagent, found in tea leaves and coffee beans, which stimulates the central nervous system. It is found in the anti-cancer drug mercaptopurine, which fights leukemia by interfering with DNA systems. A number of prepared imidazoles, including clotrimazole, are selective inhibitors of nitric oxide synthase, which makes them interesting drug targets in inflammation, respiratory diseases and tumors of the nervous system. Other biological activities of the drug carrier imidazole relate to deregulation of the intracellular fluxes of (Ca and K) ions. Novel imidazole –heterocyclic reagents were created via cyclization process then condensation process., followed by investigation of all created new reagents via a number of spectral performances (FT.IR, H.NMR)–spectrophotometric, other physical and chemical properties, and chromatographic study with microbial studying for all new created imidazole reagents.

Insight into the Mechanisms of Low Coverage Adsorption of N-Alcohols on Single Walled Carbon Nanohorn

We report for the first time the chromatographic study of n-alcohols (from methanol to butanol) adsorption on single walled carbon nanohorn (SWCNH). Using measured temperature dependence of adsorption isotherms (373–433 K) the isosteric adsorption enthalpy is calculated and compared with the data reported for a graphite surface. It is concluded that a graphite surface is more homogeneous, and the enthalpy of adsorption on SWCNHs at zero coverage correlates well with molecular diameter and polarizability, suggesting leading role of dispersive interactions, i.e., no heteroatoms presence in the walls of SWCNH structures. Next using modern DFT approach we calculate the energy of n-alcohols interactions with a graphene sheet and with a single nanocone finally proposing a more realistic—double nanocone model. Obtained results suggest alcohols entrapping between SWCNH with OH groups located toward nanocones ends, leading to the conclusions about very promising future applications of SWCNHs in catalytic reactions with participation of n-alcohols.

A new stability indicating ultra-fast liquid chromatographic (RP-UFLC) method for the quantification of Nilotinib – A drug for blood cancer

Nilotinib hydrochloride monohydrate is a tyrosine kinase inhibitor approved for the treatment of chronic myelogenous leukemia. A new stability indicating ultra-fast liquid chromatographic (RP-UFLC) method was developed for the quantification of Nilotinib and validated. Mobile phase consisting of a mixture of sodium acetate (pH 5.0): acetonitrile (40: 60, v/v) was used with flow rate 0.8 mL/min (UV detection at 254 nm) for the chromatographic study. Nilotinib obeys Beer-Lambert’s law over the concentration range of 0.2-80 μg/mL (R2 = 0.9999) with linear regression equation y = 175336x +20675. The LOQ was found to be 0.1897 μg/mL and the LOD was found to be 0.0619 μg/mL. Forced degradation studies were performed such as acidic, alkaline, oxidation and thermal degradations and the method was validated as per ICH guidelines.