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Analysis on competitive interaction between arenobufagin and verapamil hydrochloride with serum albumin  [cached]
Guo-di Lu,Hong-yue Ma
Zhong Xi Yi Jie He Xue Bao , 2011,
Abstract: Objective: The present study was performed to investigate competitive interaction between arenobufagin and verapamil hydrochloride with serum albumin.Methods: Equilibrium dialysis and high-performance liquid chromatography were used to analyze the binding rates of the two medicines to serum protein. The interactions based on bovine serum albumin (BSA) and human serum albumin (HSA) were investigated by using spectrofluorimetry. The interaction mode of arenobufagin and verapamil hydrochloride binding to serum proteins was simulated by molecular docking. Results: The rate of arenobufagin (0.1 μg/mL) binding to bovine serum was (61.1±0.2)%. Verapamil hydrochloride (0.025 to 0.1 μg/mL) significantly reduced the bovine serum binding rate of arenobufagin, from (60.2±3.7)% to (36.9±3.4)%. However, arenobufagin at the tested doses had no marked effects on the binding rate of verapamil hydrochloride. Furthermore, the verapamil hydrochloride had an active effect on the arenobufagin-induced fluorescence quenching of BSA and HSA. The molecular docking results showed that verapamil hydrochloride and arenobufagin binded to HSA at site Ⅰ . Molecular interaction energy of verapamil hydrochloride binding to site Ⅰ was stronger than that of arenobufagin. Conclusion: Verapamil hydrochloride reduces the binding of arenobufagin to bovine serum. The mechanism may be a competitive interaction of arenobufagin and verapamil hydrochloride at site Ⅰ on HSA.
Spectrophotometric Determination of Ciprofloxacin Hydrochloride in Ophthalmic Solution
Advances in Analytical Chemistry , 2012, DOI: 10.5923/j.aac.20120206.01
Abstract: The objective of this study was to develop simple and rapid method for the determination of ciprofloxacin hydrochloride in ophthalmic solution using UV spectrophotometry. The intrinsic absorbance of ciprofloxacin was measured directly at 275 nm. The calibration graph was linear over the range 2.0–7.0 μg mL-1 with relative standard deviations (RSD) values ranging from 1.55 to 2.47% (n=6). The method was validated through the parameters of linearity, accuracy, precision, limit of detection, limit of quantitation,specificity and robustnessaccording to ICH. The proposed method is enabled a quantitative determination of ciprofloxacin hydrochloride in ophthalmic solution.
Spectroscopic studies on the interaction between erlotinib hydrochloride and bovine serum albumin
F Rasoulzadeh,D Asgari,A Naseri,M.R Rashidi
DARU : Journal of Pharmaceutical Sciences , 2010,
Abstract: "nBackground and the purpose of the study: The binding ability of a drug to serum albumin has influence on the pharmacokinetics of a drug. In the present study, the mutual interaction of anticancer drug erlotinib hydrochloride with bovine serum albumin (BSA) using fluorescence and UV/vis spectroscopy was investigated. "nMethods: The BSA solution (0.1 mM) was prepared daily in Tris buffer (0.05 mol l-1, pH =7.4) and treated at final concentration of 1.67×10-5 M with different amounts of erlotinib hydrochloride to obtain final concentrations of 0, 0.2, 0.4, 0.8, 1, 2, 4, 6, 8, 20 and 42 μM receptively. The mixture was allowed to stand for 5 min and the fluorescence quenching spectra were recorded at 298, 303, 308 and 313 K. "nResults: It was found that erlotinib hydrochloride caused the fluorescence quenching of BSA by the formation of a BSA-erlotinib hydrochloride complex. The mechanism of the complex formation was then analyzed by determination of the number of binding sites, apparent binding constant Ka, and calculation of the corresponding thermodynamic parameters such as the free energy (ΔG), enthalpy (ΔH) and entropy changes (ΔS) at different temperatures. Results showed that binding of erlotinib hydrochloride to BSA was spontaneous, and the hydrophobic forces played a major role in the complex formation. The distance, r, between donor (BSA) and acceptor (erlotinib hydrochloride) was found to be less than 8 nm suggesting the occurrence of non-radiative energy transferring and static quenching between these two molecules. Conclusion: The results provided preliminary information on the binding of erlotinib hydrochloride to BSA and the presence of a single binding site on BSA and Ka values for the association of BSA with erlotinib hydrochloride increased by the increase in temperature. "n "n "n "n "n.
Drug-Drug Interactions Between Ciprofloxacin and Captopril at Binding Sites of Bovine Serum Albumin  [PDF]
S.M. Mahbubul Alam,M. Jamil Akter,M. Nadim Reza,Fatima Israt
Pakistan Journal of Biological Sciences , 2004,
Abstract: The study of drug-drug interaction between Ciprofloxacin and Captopril at binding sites of Bovine Serum Albumin (BSA) was studied by equilibrium dialysis (ED) method. During concurrent administration of these drugs, Captopril (an ACE inhibitor) and Ciprofloxacin HCl (a broad spectrum antibacterial drug) have been found to increase the free concentration of Captopril due to Ciprofloxacin causing reduced binding to BSA. The increment in free concentration of Captopril was more prominent in presence of site-II specific probe (diazepam) than in absence of same probe. When no probe and no Ciprofloxacin was added the free concentration of Captopril was only 5% whereas this release was 23% when Ciprofloxacin was added with an increasing concentration from 1 x10-5 to 12 x10-5 M. The increment of free concentration of Captopril was from 9.5% to 43% in presence of site-II specific probe upon the addition of Ciprofloxacin with an increasing concentration from 0x10-5 to 12 x10-5 M. During concurrent administration site-to-site displacement has taken place.
Simultaneous Determination of Ciprofloxacin Hydrochloride and Dexamethasone Sodium Phosphate in Eye Drops by HPLC
Prakash Katakam,Karanam R. Sireesha
Journal of Chemistry , 2012, DOI: 10.1155/2012/187824
Abstract: A liquid chromatographic method was developed and validated for the simultaneous determination of ciprofloxacin hydrochloride and dexamethasone sodium phosphate in bulk and pharmaceutical formulations. Optimum separation was achieved in less than 5 min using a C18 column (250 mmx4.6 mm i.d, 5μ particle size) by isocratic elution. The mobile phase consisting of a mixture of mixed phosphate buffer (pH 4) and acetonitrile (65:35, v/v) was used. Column effluents were monitored at 254 nm at a flow rate of 1ml/min. Retention times of ciprofloxacin hydrochloride and dexamethasone sodium phosphate were 2.0 and 3.16 min respectively. The linearity of ciprofloxacin hydrochloride and dexamethasone sodium phosphate was in the range of 3-18 μg/ml and 1-6 μg/ml respectively. Developed method was economical in terms of the time taken and amount of solvent consumed for each analysis. The method was validated and successfully applied to the simultaneous determination of ciprofloxacin hydrochloride and dexamethasone sodium phosphate in bulk and pharmaceutical formulations.
Tetracycline Hydrochloride Binds with High Affinity to Warfarin Site (Site-I) on Bovine Serum Albumin: Temperature and pH Influence the Binding Process  [PDF]
S.M. Mahbubul Alam,M.M. Rahman,M.H. Rahman,N.N. Rahman
Pakistan Journal of Biological Sciences , 2004,
Abstract: The interaction of tetracycline hydrochloride to Bovine Serum Albumin (BSA) at various temperatures and pH values using Equilibrium Dialysis (ED) method was studied. Scatchard analysis of the binding data revealed the presence of one high affinity binding site with k1 value of 1.67x106 M-1 and six low affinity binding sites with k2 value of 1.44x105 M-1 at pH 7.4 and 25°C. Site-specific probe displacement data suggested that warfarin site (site-I) is the high affinity binding site and benzodiazepine site (site-II) is the low affinity binding site on BSA for this drug. The high affinity binding site was found to be affected by temperature and pH of the medium. The thermodynamic data indicated that the binding process of tetracycline hydrochloride to BSA is spontaneous, exothermic and entropically driven. Electrostatic forces, hydrogen bonding, hydrophobic interactions and van der Waals forces are probably involved in the overall binding process of tetracycline hydrochloride to BSA. The affinity of this drug to BSA is dependent on the conformational changes of BSA caused by N-B transition.
A First-Derivative Spectrophotometric Method for the Determination of Ciprofloxacin Hydrochloride in Ophthalmic Solution
Physical Chemistry , 2012, DOI: 10.5923/j.pc.20120206.06
Abstract: A sensitive, economical and reproducible derivative visible-spectrophotometric method for determination of ciprofloxacin hydrochloride in ophthalmic solution was developed and validated. The method is based on the development of yellow colored product due the reaction between ciprofloxacin hydrochloride and Fe (III). After the reaction, the spectra of the solutions were recorded in the range of 360-500 nm and the first-derivative spectra were obtained by instrumental electronic differentiation using a delta lambda (Δλ) of 8 nm. Analytical responses were units of distance from the central zero base line to the negative peak obtained at 386.4 nm. The method was completely validated according to the ICH guidelines, showing accuracy, precision, selectivity, robustness and linearity. The proposed method is simple, of low cost and provides reliable results in order to be used in quality control of ophthalmic solutions containing ciprofloxacin hydrochloride as active substance.
In vitro microbiological evaluation of polyvinyl alcohol-based ocular inserts of Ciprofloxacin hydrochloride  [cached]
Balasubramaniam J,Srinatha A,Pandit J,Nath Gopal
Indian Journal of Pharmaceutical Sciences , 2006,
Abstract: Soluble inserts of ciprofloxacin hydrochloride using high and low molecular weight polyvinyl alcohol alone and in various combinations were fabricated by a casting technique. The in vitro drug release from the prepared inserts was studied using a continuous flow-through model, developed in our laboratory. The antimicrobial efficacies of the prepared inserts against common ocular pathogens, viz., Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853, were evaluated using a modified in vitro microbiological model. Ciprofloxacin hydrochloride release from the inserts followed matrix diffusion kinetics showing an anomalous release mechanism (erosion-controlled) based on the calculated release exponent (n) values. Drug release increased with an increase in the proportion of high molecular weight polyvinyl alcohol in the inserts. The in vitro microbiological model demonstrated the effectiveness of the inserts against the two microorganisms. Further, the results of the in vitro release studies correlated well with that of the antimicrobial studies.
Clinical studies and antimicrobial activity of ciprofloxacin hydrochloride medicated dental gels for periodontal infection  [cached]
Raghavendra Rao N,Rao K,Muthalik S,Shivanand A
Asian Journal of Pharmaceutics , 2009,
Abstract: For the effective treatment of periodontitis, ciprofloxacin hydrochloride (HCl) medicated dental gels are prepared with different hydrophilic polymers (MC, HPMC, HPC, and HEC) in different concentrations of propylene glycol. The formulations are subjected to various physicochemical studies like pH, spreadability, extrudability, viscosity, drug content, in vitro drug release, and rheological and stability studies. During the rheological studies plots of shear rate versus viscosity showed that all the gels were non-Newtonian and exhibited pseudoplastic behavior. in vitro drug release studies were carried out in the diffusion cell using a pH 7.2 phosphate buffer as a receptor medium. Formulations exhibited an extended release of the drug for over a period of 6 hours and the release depended on the type of polymer and concentrations of propylene glycol used. Stability studies showed no significant variations ( P > 0.05) in pH, spreadability, viscosity, extrudability, and drug content. An in vitro release study concluded that hydrocolloid based ciprofloxacin hydrochloride medicated dental gels appear to be probably extend the release of ciprofloxacin hydrochloride. Optimal formulations were selected for in vivo or clinical studies. The clinical evaluation of ciprofloxacin hydrochloride gels was carried out to determine the efficacy in the treatment of periodontitis. Six groups, each containing five patients, were used in the study. All the patients were evaluated for plaque index (PI) and gingival index (GI), probing depth (PD), and bleeding on probing (BOP). In all these studies, two groups were treated with formulations alone and another two groups were treated with formulations along with scaling and root planning. One group was treated with scaling and root planning only, whereas, the last group was treated as control (No treatment). All the groups showed a similar baseline PI. However, the PI values decreased remarkably in the groups treated with formulation along with scaling and root planning when compared to the other groups. Similarly, the results of GI, BOP, and PD also showed a significant reduction ( P < 0.05) in the groups treated with formulation along with scaling and root planning compared to other groups. The above studies revealed that the adjunctive use of ciprofloxacin hydrochloride gels along with scaling and root planning results in significant benefits, in the treatment of periodontitis.
DESIGN AND EVALUATION OF POLYMERIC OCULAR DRUG DELIVERY SYSTEM FOR CONTROLLED DELIVERY OF CIPROFLOXACIN HYDROCHLORIDE  [cached]
*Pawar SD,Gadhave MV,Jadhav SL,Gaikwad DD
Journal of Drug Delivery and Therapeutics , 2012,
Abstract: The field of Ocular drug delivery is one of the interesting and challenging endeavors facing the pharmaceutical scientist. The most frequently used dosage forms i.e. ophthalmic solutions and suspensions are compromised in their effectiveness by several limitations, leading poor ocular bioavailability. Ocuserts (or) Ophthalmic inserts are sterile preparations containing drug as dispersion or as solution in the polymeric support. Ocusert helps to improve ocular bioavailability by increasing the duration of contact with corneal tissue, thereby reducing the frequency of administration. Ciprofloxacin is a fluoroquinolone antibacterial drug effective in the treatment of bacterial conjunctivitis. The ciprofloxacin hydrochloride ocuserts were then evaluated for their physicochemical parameters like uniformity of thickness, weight, drug content and in vitro release pattern. It can be concluded that this ocular inserts formulation can be a promising for controlled release formulation.
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