Amount Of Ampicillin Research Articles

Highly efficient modified lead oxide electrode using a spin coating/electrodeposition mode on titanium for electrochemical treatment of pharmaceutical pollutant

In this study, Ti/TiO2/PbO2 anodes consisting of a PbO2 coating growth on the TiO2 interlayer deposited on titanium substrates were prepared combining different deposition technics: electrochemical method using anodization (Anod), electrodeposition (EL), and sol gel spin coating (SG). Different kinds of anodes have been tested for the removal of ampicillin, a pharmaceutical pollutant, from water. The structure and the surface morphology of the prepared multiple coatings were characterized by scanning electron microscopy and Energy-Dispersive X-ray spectroscopy respectively. Electrochemical impedance spectroscopy was also investigated in order to study the electrocatalytic activity of the anodes. The performance of the electrodes was evaluated through high performance liquid chromatography and chemical oxygen demand (COD) measurements. It was noticed that ampicillin could be mineralized by anodic oxidation process using Ti/TiO2/PbO2 anodes. The best results were obtained for Ti/TiO2SG/PbO2EL as anode with a 64% of COD removal after 300 min of treatment and a fast decrease in the amount of ampicillin was reached after almost one hour. Experimental results demonstrate that Ti/TiO2SG/PbO2EL anode presents the best ability for the degradation of ampicillin through anodic oxidation compared to the Ti/TiO2SG/PbO2SG and Ti/TiO2Anod/PbO2EL electrodes.

Fluorogenic pH-Sensitive Polydiacetylene (PDA) Liposomes as a Drug Carrier

A crucial issue for current liposomal carriers in clinical applications is the sustained-release property of the encapsulated drugs. We have developed novel fluorogenic pH-sensitive polymerized liposomes composed of polydiacetylene (PDA) lipids and other types of lipids. Unilamellar liposomes containing 10,12-pentacosadiynoic acid (PCDA), 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), and N-palmitoyl homocysteine (PHC) were loaded with ampicillin. These liposomes fused to each other rapidly when the medium pH was lowered from 7 to 4. The polymerized liposomes were characterized in terms of particle size distribution. The liposome size increased approximately 20-fold from 110.0 +/- 19.3 nm to 2046.7 +/- 487.4 nm as the pH was lowered. Cross-linking of the diacetylene lipids prevents drug leakage and the encapsulated drug can be instantaneously released at acidic pH condition. The ampicillin was nearly completely released (74.4 +/- 3.9%) from liposomes within 4 h under acidic pH conditions and the released amounts of ampicillin were analyzed by HPLC. Finally, the therapeutic effect was observed by the appearance of plaques on a lawn of E. coli, and fluorescent images of the PDA liposomes were taken from the plaques for drug release monitoring. As a result, this research demonstrates that such novel pH-sensitive polymerized liposomes have great prospects as a drug carrier.

Laser interferometry analysis of ciprofloxacin and ampicillin diffusion from liposomal solutions to water phase

The paper presents experimental investigations of diffusion of antibiotics (ciprofloxacin or ampicillin) into the water phase from mixtures of neutral or negatively charged liposomes, and antibiotic–liposome interactions. Using the laser interferometry technique, the amounts and fluxes of released antibiotics, concentration field evolution, and the velocity of the concentration boundary layer’s “growth” were determined. To avoid the limitations of membranes, a measurement system without the artificial boundary of phases with a free water–solution interface has been proposed. It was found that the diffusion of anionic and neutral liposomes into the water phase was insignificant and mainly the diffusion of antibiotics was measured. Differences in the diffusion kinetics of ciprofloxacin and ampicillin from liposomal solutions to the water phase were observed. Ampicillin diffused more efficiently than ciprofloxacin regardless of the liposomal solution type. Moreover, the amount of ampicillin and ciprofloxacin released from the anionic liposomal phase was higher than that from the neutral one. Our results confirm that ciprofloxacin at neutral pH shows little tendency to bind neutral liposomes. Additionally, it was also observed that ciprofloxacin disrupts negatively charged liposomes as a final effect of antibiotic–lipid interactions.

Application of the Laser Interferometry in Studies of Biophysical Model Systems

Abstract In this paper some selected applications of laser interferometry method in studies of biophysical model systems are presented. With the aid of a laser interferometric method, specific experiments were performed, which confirm that the gravitational field significantly modifies the amount of transported substance and affects the concentration profiles as well as the time evolution of the concentration field. The laser interferometry was also used to investigation of diffusion of antibiotics (ciprofloxacin or ampicillin) into the water phase from mixtures of neutral or negatively charged liposomes, and antibiotic-liposome interactions. Differences in the diffusion kinetics of ciprofloxacin and ampicillin from liposomal solutions to the water phase were observed. Moreover, the amount of ampicillin and ciprofloxacin released from the anionic liposomal phase was higher than that from the neutral one.

Stability Test of Ampicillin Sodium Solutions in the Accufuser® Elastomeric Infusion Device Using HPLC: UV Method

The stabilities of two kinds of solutions (30 mg/mL) of Ampicillin sodium in 0.9% NaCl in water (NS, normal saline) and in sterile water (SW) in the intravenous elastomeric infusion device (Accufuser?) were evaluated based on recommended solutions and storage periods. The injectable NS- and SW-Ampicillin solutions in the Accufuser? device were stored and evaluated at controlled temperature (room temperature, 25℃ ± 2℃ and cold temperature, 4℃ ± 2℃) during 7 days. Effects of the periods of storage (from 0 to 7 days) and the temperatures of storage (RT and CT) on the physico-chemical appearances and concentrations of active compounds were determined. The visual clarity, pH, and concentrations of Ampicillin were determined by stability-indicating high-performance liquid chromatography (HPLC)-ultraviolet (UV) detection. The results showed that the amount of Ampicillin in studied solutions gradually decreased with time. The Ampicillin in NS, which was stored in CT, was relatively stable, retaining 94% of its original amount up to 7 days. The solution that showed least stability was Ampicillin in SW, which was stored in RT, retaining 80% of its original amount. Generally, solutions that were stored in CT were more stable than the solutions that were stored in RT. No significant changes in physical appearance or color of the solutions were observed during the study. Particles were not detected in any solution samples. In summary, two kinds of solutions of Ampicillin sodium, in NS and SW, showed different chemical stabilities with time in intravenous infusion device without any significant physical changes and retained about 94% vs 89% and 83% vs 80% of initial concentrations after 7 days in CT and RT, respectively. We suggest that 30 mg/mL of Ampicillin sodium in NS solution in an Accufuser? infusion device which is stored in CT can be applicable for 7 days in clinical situations.

Laser interferometric determination of ampicillin and colistin transfer through cellulose biomembrane in the presence of Proteus vulgaris O25 lipopolysaccharide

Ampicillin is a beta-lactam antibiotic which inhibits transpeptidation during bacterial cell-wall peptidoglycan synthesis. Colistin (polymyxin E) is a cyclopeptide antibiotic that disrupts plasma membrane structures of sensitive Gram-negative bacteria. The first step of colistin anti-bacterial action is binding to outer membrane lipopolysaccharides (endotoxins, LPSs). The aim of this investigation was to compare the diffusion process of ampicillin and colistin in the absence and presence of Proteus vulgaris O25 native and O-deacylated forms of LPS by laser interferometry. Antibiotics and LPSs at concentrations of 4 mg/ml and 100 μg/ml, respectively, were used. The interferometric system consisted of a Mach-Zehnder interferometer with a He-Ne laser, TV-CCD camera, computerised data acquisition system, and a membrane system with two cuvettes separated by a horizontally placed cellulose membrane. Diffusion of the substance through a membrane separating solutions of different concentrations leads to the formation of concentration boundary layers (CBLs). Computer-assisted analysis of the antibiotic CBLs showed that the amount of ampicillin and colistin transported through the membrane was not influenced by the presence of O25 LPSs, in contrast to colistin diffusion, which depended on the O-deacylated form of O25 LPS. The diffusion coefficient of colistin was 1.7 times greater in the presence than in the absence of endotoxin. The ionic interaction between colistin and O25 LPSs may have facilitated the transport through the membrane.

Absorption of ester prodrugs in Caco-2 and rat intestine models.

The aim of this study was to elucidate the absorption mechanism in Caco-2 and rat intestine models in order to improve the accuracy of prediction of oral absorption of ester prodrugs. Pivampicillin and cefcapene pivoxil hydrochloride (CFPN-PI), ester-type oral antibiotics, were chosen as model ester prodrugs. The level of esterase activity in Caco-2 cells was lower than that measured in the rat jejunum when p-nitrophenyl acetate was used as a substrate. Almost complete ester hydrolysis occurred before the ester prodrugs reached the basolateral side of the monolayer, and the disappearance of prodrugs was thought to be due to metabolism or transport after addition to the apical side of the monolayer. When pivampicillin and CFPN-PI were used, the amounts of ampicillin and cefcapene (CFPN) produced by hydrolysis of prodrugs were increased because intracellular degradation of prodrugs resulted in intracellular accumulation. On the other hand, when ampicillin or CFPN was used, only a small amount of the drug reached the basolateral side of the monolayers and no intracellular accumulation was observed. The permeability of CFPN-PI, the solubility of which is dependent on the acidity of gastric juice, across a Caco-2 monolayer or rat intestine, was also investigated by using an in vitro system that mimics the physiological state of the human gastrointestinal tract. The oral absorption of CFPN-PI in humans is predicted to be good either in the Caco-2 model or in the rat intestine model. It is concluded that our system may be a valuable tool for evaluation of oral absorption of ester prodrugs metabolized during permeation through the intestinal epithelium. Broader evaluation of such a system is warranted.

Synthesis and Properties of Dextran-Linked Ampicillin

Ampicillin was coupled to dextran of average molecular weight 9,000 or 81,200 via the cyanogen bromide method. The degree of drug substituted per glucose unit (DSG) was varied from 0.104 to 0.028 (by weight bases: 22.1–5.9%) depending on the ratio of the reactants. Water solubility of dextran-linked ampicillin increased compared with free ampicillin, and the solubility decreased as the amount of ampicillin substituted increased. Plasma concentration of ampicillin, which appeared after intravenous administration of dextran-linked ampicillin in rats, was higher than when free ampicillin was administered, and the more so, the higher the molecular weight of dextran. Plasma half-life of dextran-linked ampicillin was two times longer than that of free ampicillin in rats. Antibacterial activities of dextran-linked ampicillin were evaluated against Staphylococcus aureus, Bacillus substillis, and Escherichia coli at two concentration levels according to the cup-plate method by measuring the diameter of inhibition zone, which was comparable to that of free ampicillin.

Sustained release of antimicrobials in the middle ear using a biodegradable support.

The ototoxicity of a poly-L-lactic acid biodegradable support incorporating a therapeutically releasable amount of ampicillin was studied. This device has a shape that allows placement in the middle ear via a myringotomy incision. Once in the middle ear, it expands without mechanical interference and provides extended release of ampicillin. In vitro studies documented sustained release of ampicillin, and in vivo efficacy was demonstrated in otitis media induced in chinchillas and cats. Previous histopathologic studies showed a lack of inflammatory reaction from the device itself and documented its biodegradable characteristics. There was no evidence of ototoxicity on morphometry of the organ of Corti (hair cell counts) in chinchillas exposed to these devices for 3 weeks with and without ampicillin.

Proposed changes in interpretive criteria and potency of ampicillin and ampicillin-sulbactam disks for susceptibility tests.

The accuracy of disk susceptibility tests with ampicillin and ampicillin-sulbactam was not improved when the amount of ampicillin was increased from 10 to 20 or 30 micrograms per disk. For testing members of the family Enterobacteriaceae, ampicillin disk tests correlated better with broth microdilution tests when the zone size standards were altered from greater than or equal to 14 greater than or equal to 17 mm for susceptible and from less than or equal to 11 to less than or equal to 13 mm for resistant. The same zone size breakpoints apply to tests with ampicillin-sulbactam disks (10/10 micrograms). When Staphylococcus, Branhamella, and Haemophilus species are tested against ampicillin, interpretive breakpoints are those separating beta-lactamase-producing strains from nonproducing strains. However, when ampicillin-sulbactam is tested, beta-lactamase enzymes are efficiently inhibited by the sulbactam component, and thus zone size standards for ampicillin do not apply: zone size standards for the Enterobacteriaceae can be used for testing the combination against Staphylococcus, Branhamella, and Haemophilus species. For Streptococcus, Enterococcus, and Listeria species, only ampicillin disks need be tested, since ampicillin-sulbactam disks give essentially identical results.

Spectrophotometric determination of microgram amounts of ampicillin with chloranil

Ampicillin trihydrate (12.5–750 μg) is determined spectrophotometrically using chloranil as π-acceptor at pH 9. The method is relatively accurate (with a recovery of 100 ± 1.0%) and precise (RSD ⩽ 1.7%) and can be used successfully for capsules and ampoules.

Correlation between microbiological and chemical assay of ampicillin in bioequivalence studies in man

Using the urinary excretion method, the bioavailability of ampicillin from two commercially available brands was investigated. The amounts of ampicillin in urine were determined chemically and microbiologically. The results indicate good agreement between the chemical and microbiological assay methods. The chemical assay was recommended as the method of choice for the assay of ampicillin in bioequivalence studies. Using this method the two brands were found not to be bioequivalent.

Penetration of ampicillin into urethral and cervical secretions after oral administration of bacampicillin.

The study comprised 24 male and 24 female patients treated either for uncomplicated gonorrhoea or as a prophylaxis. A single dose of 800 mg of bacampicillin + 1.0 g probenecid was administered orally to each patient. The concentrations of ampicillin in urethra and cervix were assayed by means of alginate swabs that were used as diffusion centres on agar diffusion plates. The inhibition zones were compared with a standard series of swabs containing known amounts of ampicillin. The amounts of secretions absorbed into the swabs were determined by weighing each swab before and after taking the specimen. The median ampicillin concentration in the male urethra one hour after the single dose of bacampicillin plus probenecid was 2.0 micrograms/ml of urethral secretion and increased to 3.2 micrograms/ml two hours after administration of the antibiotic. In the female urethra, the median concentrations of ampicillin were 1.5 micrograms/ml and 2.3 micrograms/ml of urethral secretion one and two hours, respectively, after the same dosage as above. The corresponding ampicillin concentrations in the cervical secretion were 1.6 micrograms/ml and 2.9 micrograms/ml, respectively.

Effects of subminimal inhibitory concentrations of ampicillin, chloramphenicol, and nitrofurantoin on the attachment of Escherichia coli to human uroepithelial cells in vitro.

An in vitro system with epithelial cells of the human urinary tract and Escherichia coli isolated from the urine of pateints with acute pyelonephritis was used for tests of the effect of antibacterial agents on bacterial adhesion. E. coli treated with subminimal inhibitory amounts of ampicillin attached less than untreated control bacteria. Subminimal inhibitory amounts of chloramphenicol and nitrofurantoin had no effect on adhesion of the 15 strains of E. coli tested. The combination of bacterial pretreatment with ampicillin and addition of antibodies to the adhesion test tube decreased adhesion more than did either treatment separately.

Possible .BETA.-lactamase activities detectable in infective clinical specimens.

Biological beta-lactam antibiotic-inactivating activities were detected in bacteriuria and suppurating pleural fluids. Clinical specimens were sterilized with membrane filters and the amounts of ampicillin and/or cephalothin which were being inactivated by 1 ml of each filtrate were determined. In general, filtrates which originally yielded Klebsiella sp. tended to show activity against ampicillin; whereas those yielding Enterobacter sp. and Pseudomonas aeruginosa showed activity against cephalothin.

Biliary excretion of ampicillin: experimental and clinical study.

The biliary excretion of ampicillin was studied in various conditions. Using an isolated perfused rabbit liver preparation, 4.1% of the amount of ampicillin added to the circulating blood (10 mg) was recovered in the bile where the maximum antibiotic activity (mean: 104 +/- microng/ml) was 4 times higher than in the serum (mean: 24.1 +/- 3.4 microng/ml). In man, provided with T-tube drain, the oral or intravenous administration of 500 mg ampicillin resulted in a biliary excretion of 0.10% of the administered dose. The biliary concentrations thus obtained equalled or exceeded for several hours the minimal inhibitory concentration of the organisms included in the antibacterila spectrum of ampicillin justifying thus the use of this antibiotic in the treatment of biliary tract infections. Per-operatory assays showed that in patients with gallbladder disease or with cystic duct obstruction, ampicillin levels in the gallbladder bile were markedly lower than in the common duct bile.

The ampicillin concentration in prostatic tissue and prostatic fluid.

The concentration of ampicillin in prostatic fluid, prostatic tissue, blood and urine was determined in different groups of patients and dogs using bioassays. The concentration found in prostatic fluid was as high as that of blood and in patients with chronic prostatitis slightly higher. It is shown that this is probably due to contamination of prostatic fluid with urine, even if care had been taken to minimize this possibility. The importance of considering this factor in similar experiments is stressed. Only insignificant amounts of ampicillin were found in prostatic tissue removed at open prostatic surgery. Ampicillin was not found in therapeutic concentration in prostatic fluid of a patient with ureterosigmoidostomy and of dogs in which a prostatic fistula previously had been made. It is concluded that ampicillin is not found in prostatic tissue and prostatic fluid in therapeutic concentrations and therefore doubtful whether ampicillin will benefit patients with chronic prostatitis.