High-efficiency Liquid Chromatography Research Articles

Standardization and validation of a high-efficiency liquid chromatography with a diode-array detector (HPLC-DAD) for voriconazole blood level determination.

A specialized service for antifungal blood level determination is not available in Colombia. This service is essential for the proper follow-up of antifungal therapies. To standardize and validate a simple, sensitive, and specific protocol based on high-performance liquid chromatography with a diode array detector for voriconazole blood level quantification. We used an Agilent HPLC™ series-1200 equipment with a UVdiode array detector with an analytical column Eclipse XDB-C18 and pre-column Eclipse- XDB-C18 (Agilent). We used voriconazole as the primary control and posaconazole as an internal control. We performed the validation following the Food and Drug Administration (FDA) recommendations. The best chromatographic conditions were: Column temperature of 25°C, UV variable wavelength detection at 256 nm for voriconazole and 261 nm for posaconazole (internal standard); 50 μl of injection volume, 0,8 ml/min volume flow, 10 minutes of run time, and mobile phase of acetonitrile:water (60:40). Finally, retention times were 3.13 for voriconazole and 5.16 minutes for posaconazole. Quantification range varied from 0.125 μg/ml to 16 μg/ml. The selectivity and chromatographic purity of the obtained signal, the detection limits, and the standardized quantification make this method an excellent tool for the therapeutic monitoring of patients treated with voriconazole.

Phytochemical screening and identification of metabolites by LC-ESI-IT-MS/MS and FIA-ESI- IT-MS of the hydroalcoholic extract of Annona exsucca DC leaves

This work studies the chemical composition of the leaves of the plant species Annona exsucca DC. Through phytochemical tests and analysis by high efficiency liquid chromatography coupled to mass spectrometer with electrospray ionization source (LC-ESI-IT-MS/MS) and ion trap type analyzer in addition to direct infusion experiments (FIA-ESI- IT-MS) it was possible to determine the classes of secondary metabolites present in the leaves of this species and to characterize some of these substances, respectively. The results obtained with the phytochemical tests confirmed the presence of alkaloids, flavonoids, steroids, tannins and saponins. While the results obtained by mass spectrometry allowed the characterization of some alkaloids.

On-Chip Comparison of the Performance of First- and Second-Generation Micropillar Array Columns.

Because of its dimensions, the recently introduced micropillar array columns are most suited for high-efficiency liquid chromatography separations in proteomics. Unlike the packed bed columns and capillary-based column formats, the micropillar array concept still has significant room to progress in terms of the reduction of its characteristic size (i.e., pillar diameter and interpillar distance) to open the road to even higher-efficiency separations and their applications. We report here on the on-chip comparison between first-generation (Gen 1) and second-generation (Gen 2) micropillar array columns wherein the pillar and interpillar size have been halved. Because of the on-chip measurements, the observed plate heights H represent the fundamental band broadening, devoid of any extra-column band-broadening effects. The observed reduction of H with a factor of 2 around the uopt-velocity and with a factor of 4 in the C-term dominated regime of the van Deemter-curve is in full agreement with the theoretically expected gain. This shows the pillar and interpillar size reduction could be effectuated without affecting the theoretical separation potential of the micropillar arrays. Compared to Gen 1, Gen 2 offers a 4-fold reduction of the required analysis time around the optimal velocity and about a 16-fold reduction in the C-term-dominated range.

A validated LC-MS/MS method for the quantification of bevacizumab in rat, cynomolgus monkey, and human serum

Bevacizumab is a humanized monoclonal antibody used in the treatment of advanced colorectal and non-small cell lung cancer. Our main aim was to establish a simple, economical, and high efficiency liquid chromatography tandem mass spectrometry (LC-MS/MS) method for quantifying the content of bevacizumab in various biological fluids (rat, cynomolgus monkey, and human serum). A surrogate peptide of bevacizumab, specifically FTFSLDTSK, was generated through trypsin hydrolysis, and quantified using an isotopically labeled peptide containing two amino acids, FTFSLDTSK[13C6, 15N2]ST, as an internal standard to correct for variations introduced during the enzymatic hydrolysis process and any mass spectrometry variabilities. The pre-treatment process included denaturation, disulfide bond reduction and alkylation, trypsin hydrolysis, and termination of the reaction, with a total duration of approximately 2.5–3 h. The results of the methodological validation showed that the linear range in three different biological matrices was 0.2 µg/mL to300 µg/mL, with an LLOQ of 0.2 µg/mL. The precision and accuracy of the measurements met the required standards. The validated LC-MS/MS method was used to conduct pharmacokinetic analysis in rats administered bevacizumab at a dose of 10 mg/kg intravenously.

Structure and Vibrational Spectroscopy of C82 Fullerenol Valent Isomers: An Experimental and Theoretical Joint Study

Gd@C82OxHy endohedral complexes for advanced biomedical applications (computer tomography, cancer treatment, etc.) were synthesized using high-frequency arc plasma discharge through a mixture of graphite and Gd2O3 oxide. The Gd@C82 endohedral complex was isolated by high-efficiency liquid chromatography and consequently oxidized with the formation of a family of Gd endohedral fullerenols with gross formula Gd@C82O8(OH)20. Fourier-transformed infrared (FTIR) spectroscopy was used to study the structure and spectroscopic properties of the complexes in combination with the DFTB3 electronic structure calculations and infrared spectra simulations. It was shown that the main IR spectral features are formed by a fullerenole C82 cage that allows one to consider the force constants at the DFTB3 level of theory without consideration of gadolinium endohedral ions inside the carbon cage. Based on the comparison of experimental FTIR and theoretical DFTB3 IR spectra, it was found that oxidation of the C82 cage causes the formation of Gd@C82O28H20, with a breakdown of the integrity of the parent C82 cage with the formation of pores between neighboring carbonyl and carboxyl groups. The Gd@C82O6(OOH)2(OH)18 endohedral complex with epoxy, carbonyl and carboxyl groups was considered the most reliable fullerenole structural model.

Quantification of 3,5,7,3'-4'-pentahydroxflavona of the aerial parts of p. Guajava

Psidium guajava is popularly known as guava. It is a very common species in South America, found most often in tropical climate. It is a plant known for its anti-inflammatory property, used in folk medicine for combating intestinal discomfort, colic, colitis, among others. The leaves of P. guajava present flavonoids in their composition, with emphasis on quercetin. The flavonoid class has antioxidant properties and acts on the central nervous system through oxidative inhibition of the endoplasmic reticulum. Thus, the objective of this study was to quantify the quercetin of the aerial parts of guava. Therefore, ethanol extraction was performed, followed by fractionation with solvents of different polarities, obtaining the hexanic, dichloromethane and ethyl acetate fractions. Then, quercetin was identified in the ethyl acetate fraction by Thin Layer Chromatography (CCD), the total flavonoid content was quantified by spectrophotometry and quercetin by High Efficiency Liquid Chromatography (HPLC). The qualitative analysis in CCD of the ethyl acetate fraction revealed the presence of flavonoids. Quantitative spectrophotometry analysis showed 46.2 mg of total flavonoids per g of the ethyl acetate fraction, being 816 μg g-1 of quercetin revealed by HPLC. With this study, it was possible to identify the presence of flavonoids, and about 2% correspond to the substance quercetin, present in the ethyl acetate fraction of P. guajava. Therefore, further studies can be carried out aiming at the isolation of quercetin for application in a pharmaceutical form acting on the central nervous system.

CHEMICAL COMPOSITION OF GERANIUM WLASSOVIANUM (GERANIACEAE)

The article presents the results of experimental findings concerning the study of the chemical composition of above-ground and underground parts of Geranium wlassovianum. The amount of number of tannins into the plant matter gathered during the blooming period is 19.45±0.04% in the root system and 20.93±0.03% in the above-ground part of a plant. Tannins are referred to phenolic compounds. For qualitative determination of peculiar phenolic compounds the HELC (high-efficiency liquid chromatography) method was used. This method allowed to determine 21 compounds from the aqueous extract of the above-ground parts and 11 compounds from the aqueous extract of the underground parts of the Geranium wlassovianum. 8 compounds were found both in the shoot system and in the root one, 13 substances are contained only in the grass, 3 substances were found only in the underground plant parts. During the study, the elemental composition of a plant was identified, as a result 22 chemical elements were found out. For 6 elements the root barrier index is lower than one that points at barrier-free transition of elements from a root system to an above-ground parts of a plant. The rest 16 elements meet the barrier during transition (in the range from 1 to 10), that is the concentration of these 16 elements is higher in the underground part than in the grass part. The variety of the chemical composition and quantitative content of the chemical elements in the plant matter of the species that is under the research depend on different natural factors.

Investigation of Herbicide Decomposition Efficiency by Means of Detonative Combustion

The decomposition of seven herbicides (atrazine, linuron, lenacil, chloridazon, dinoseb acetate, prometryn, and diuron) was carried out by detonative combustion. The investigated blasting material was produced on the basis of porous ammonium nitrate, which served as an oxidizer, while the pesticides played the role of the fuel. Detonative decomposition of the mixtures was carried out in blast-holes in soil. The efficiency of the decomposition process was assessed using the techniques of gas chromatography, high-efficiency liquid chromatography, and additionally by biological tests according to the grading of the European Weed Research Council. The results demonstrate an efficient decomposition of the tested herbicides. In the tested soil samples taken after the detonation decomposition of the herbicide, no symptoms of phytotoxic effects on the plants were found. This was confirmed by the lack (or at most negligible amounts) of residual herbicides in the soil samples. Only for the samples of chloradizine and diuron were large amounts of residual biologically active substance found.

Agronomic and physicochemical parameters of must and wine as a function of changes in ‘Cabernet Sauvignon’ grapevine canopy

This study aimed to evaluate the influence of vegetative canopy height on the agronomic characteristics and grape must and wine physicochemical properties of a ‘Cabernet Sauvignon’ vineyard in an espalier-trained system. The evaluated parameters comprised agronomic characteristics of ‘Cabernet Sauvignon’ grapevines and physicochemical compositions of ‘Cabernet Sauvignon’ musts and wines, as well as their phenolic compositions (anthocyanins, stilbenes, and flavonoids), and impact on wine contents of methoxypyrazines (volatile compounds that impart vegetal or earthy odors to wine, which are considered undesirable in large intensity). To that end, four heights of the vegetative canopy were tested: 60 cm (T1), 80 cm (T2), 100 cm (T3), and 120 cm (T4). The experiment was carried out in a commercial vineyard in the region of “Campanha Gaúcha” (Dom Pedrito, Rio Grande do Sul State, Brazil) during the productive cycles of 2015/16, 2016/17, 2017/18, and 2018/19. The main agronomic parameters were measured: estimated productivity per plant and hectare, and mean weight and number of clusters. All wines were elaborated by the same traditional winemaking methods. The physicochemical analyses of must and wines were performed by infrared spectroscopy using Fourier Transform Infrared Spectrometer (FTIR), and the phenolic analysis by high-efficiency liquid chromatography and UV-Vis spectrophotometry. Methoxypyrazines were quantified using headspace solid-phase microextraction (HS-SPME), followed by gas chromatography-mass spectrometry (GC-MS). The results showed that treatments did not influence agronomic parameters. However, technological maturation (sugar accumulation) had interesting results for plants managed at higher canopy heights, with respective results obtained for wine. Treatments had little influence on individual quantification of anthocyanins, although cycles had a high influence on their profile. The wines had low concentrations of methoxypyrazines and did not differ among treatments.

Development of methods of determination of biological liquids by high-performance liquid chromatography of acetamiprid pesticide

Acetamiprid development of moderate conditions of high-performance liquid chromatography method in the separation of biological fluids from blood and urine. The analysis (Shimadzu Corporation) was carried out on a high-performance liquid chromatograph SPD–M20A, equipped with a model LC-20 Prominence (US) diode matrix UV-detector autosamplers. The process consists of a four-channel gradient type pump designed for high-pressure operation, a spectrophotometric detector with a wavelength of 190–360 nm, and a measuring device with a volume of 20 μL – “Rheodyne” injector and a chromatographic column. The research was conducted under the following conditions: – Perfect Sil 300 ODS C18 with chromatographic steel column particle size 5 μm. Filled with the sorbent, size 150 × 4.6 mm; – excited phase acetonitrile-water 70:30; – reduction phase flow -0.75 ml/min; – Sample size for analysis – 20mkl; – detector wavelength 246 nm; – analysis time 10 minutes. Acetamiprid was weighed to 0.01 g (a.t), dissolved in a 50 mL volumetric flask with a mobile phase, and the volume of the solution was delivered by the mobile phase to the mark. From this solution, standard working solutions of acetamiprid were prepared and the separation time of acetamiprid was determined. As a result of the analysis, the retention time of acetamiprid on the chromatogram was 2.314 minutes in the blood and 2.722 minutes in the urine. The obtained results were determined by metrological analysis with 67.56% separation of acetamiprid from model blood samples with a relative error of 1.63%, with a relative error of 73.98% with acetamiprid of the model urine sample. The retention time of acetamiprid pesticide in the standard sample under the conditions developed by the HPLC method was 2,190 minutes. Chromatographic peaks were formed in the test blood sample, which lasted 2,314 minutes, and 2.722 minutes in the urine. The amount of acetamiprid isolated from model blood and urine samples was 67.56% in the blood and 73.28% in the urine during metrological analysis. Moderate conditions for the detection of acetamiprid by high-efficiency liquid chromatography have been developed. On the chromatogram, acetamiprid was identified by chromatographic peaks with a retention time of 2,190 minutes in standard samples. When the samples tested were also chromatographed, values equal to the retention time of standard acetamiprid were recorded. Under the conditions of the developed analysis, positive results were obtained and 67.56% of biological fluids were isolated from blood samples and 73.28% from urine samples. The developed methods of analysis were applied to the detection of biological fluids, and pesticides isolated from them.

Stability of vancomycin hydrochloride employed in antimicrobial seal solutions of central intravenous catheters

Objective: to verify the stability of vancomycin hydrochloride in antimicrobial seal solutions with and without association of heparin sodium according to temperature and association time. Method: an experimental study designed for the analysis of hydrogenionic potential and concentration by means of high-efficiency liquid chromatography of vancomycin hydrochloride (n=06) and vancomycin hydrochloride and heparin sodium (n=06). The solutions studied were submitted to absence of light, as well as to 22°C and 37°C. Analyses in triplicate (n=192) were performed at the initial moment (T0) and three (T3), eight (T8) and 24 hours (T24) after preparation. The data were submitted to analysis of variance (p≤0.05). Results: concentration of the antimicrobial at 22°C presented a reduction (T0-T8) and a subsequent increase (T24); hydrogenionic potential decreased significantly over time. At 37°C, the concentration increased up to T3 and decreased at T24, with a reduction of hydrogenionic potential up to 24 hours. Concentration of the vancomycin hydrochloride and heparin sodium solutions varied with a reduction at 22°C, accompanied by increased hydrogenionic potential. Precipitate formation was observed by visual inspection of the vancomycin hydrochloride-heparin sodium association (T3). Conclusion: pharmacological stability of vancomycin hydrochloride (5 mg/mL) and physical incompatibility with heparin sodium (100 IU/mL) were evidenced after three hours of association in the antimicrobial seal solutions studied.

Hygienic Monitoring of Working Area Air Pollution by Particulate Matter of ticagrelator in the Pharmaceutical Factory

Introduction. Hygienic monitoring of air pollution at the pharmaceutical enterprise required by the law of the Russian Federation (orders, standards, methodological guidelines and guidelines). This requirement follows from the need to protect the personnel of the pharmaceutical plant from the adverse air conditions of the working area, which may contain suspended solids of active pharmaceutical ingredient (API). Despite the use of breathing equipment by staff and occupational safety requirements, the risk to workers should be minimized by regular assessment of air pollution. Aim. The purpose of the stady is to carry out hygienic monitoring of working area air tikagrelor – API of the medicinal preparation Brilinta®. Materials and methods. The subject of this research is API ticagrelor including air and flush samples from the surface of LLC «AstraZenica Industries», collected during the production of the consignment of Brilinta® (MNN – ticagrelor). Air samples of the working area were collected using air intake systems of type "IOM Sampler", using both personal and stationary systems. Flushing from the surface is done by template v printing using cotton swaps. Sampling points selected to cover. All stages of the production cycle. Subsequently, the quantification of ticagrelor in samples was carried out by the method of high-efficiency liquid chromatography with UV detection (HPLC-UV). Results and discussions. The quantitative determination showed that 4 air samples and 25 surface fluxes exceeding the allowable content of ticagrelor. Each sample was related to the time and place of sampling, and assumptions were made as to why the sample points exceeded the standard values. Conclusion. At the pharmaceutical enterprise we have carried out hygienic monitoring of the working area air for the content of API ticagrelor. The results of the measurements were obtained and processed, on the basis of which measures were proposed to reduce the concentration of ticagrelor in the air in order to protect personnel from the adverse effects of the work area. These measures include optimization of process operations and/or training of personnel in new approaches to the operation and cleaning of equipment.

In vitro effect of cocoa leachates on growth and development of Moniliophthora roreri ([Cif.] H.C. Evans et al.) isolated from Theobroma cacao (L.)

The cocoa crop is part of the peasant’s economic activity and agroforestry systems in many regions of Colombia and the world. Its yields are diminished by phytosanitary problems, being the frosty pod rot caused by the fungus Moniliophthora roreri, the most limiting disease with decreases in production of over 90%. In this study, samples of cocoa leachates from commercial producing farms were characterized and the antifungal activity of sterilized, non-sterilized, and filtered cocoa leachates against M. roreri was evaluated under in vitro conditions, at concentrations of 1, 2, 5, 10, and 15%. Monosporic isolates of the pathogen were obtained from diseased fruits collected from cocoa-producing farms in the municipality of Yacopi in Cundinamarca, Colombia. The effect of leachates on M. roreri conidial germination, mycelial growth, and inoculum production was evaluated. It was found that non-sterilized cocoa leachates at all concentrations caused 100% reduction on the three variables evaluated, while sterilized leachates generated the same effect at concentrations of 10 and 15%. Filtered leachates showed no inhibitory effect on the radial growth of the pathogen, but they caused a reduction of conidial germination of 89.9, 90.5 and 95.9% at concentrations of 5, 10, and 15%. The presence of malic, citric, and ascorbic acids, compounds such as NH4, PO4, and NO3, and elements such as Ca, K, Na, Mg, and Cl in the evaluated leachates was identified using high-efficiency liquid chromatography and physicochemical analysis. This research showed the potential of cocoa leachates, even at low concentrations, for the control of M. roreri, which can be attributed to the action of specific compounds such as those found in chromatographic tests.

Development of the stability-indicating method, structural elucidation of new photodegradation products from terconazole by LC-MS TOF, and in vitro toxicity

Terconazole (TCZ) was the first triazole antifungal drug launched in the market and has been used in the treatment of vulvovaginal candidiasis. It is also indicated to treat dermatophytosis and fungal ocular infections. However, some of the degradation products from triazole drugs have been reported to be toxic, justifying the need of further investigations about the stability of TCZ. identification of its degradation products and evaluation of their toxicity considering the new possibilities of therapeutic indications. Therefore, in this work a systematic investigation regarding photostability of TCZ was conducted. The active pharmaceutical ingredient (API) and its methanolic solution (100 µg mL−1) were kept into a photostability chamber under a UV light (200 Wh/m2; 1.2 × 106 lux/h) during 5 days and 90 min, respectively. A high-efficiency liquid chromatography method was developed for separation and identification of TCZ and its degradation products. The solid-state API remained stable throughout the test, whereas an extensive degradation was observed when in solution. In this case, four degradation products not yet reported in the literature were identified and characterized by electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (ESI-QTOF-MS). Two degradation products presented m/z of 498 and the other two of 496 and 464, respectively. The results suggest that the degradation follows a first-order kinetic and involves the loss of chlorine atoms from the 2,4-dichlrophenyl moiety. Finally, TCZ submitted to the same stress condition as the API solution, increased significantly the opacity during the bovine corneal opacity and permeability test method (BCOP) indicating a potential to cause ocular toxicity. Further studies using the pure photolysis degradation products of TCZ characterized in this work are still necessary to confirm this find.

ENERGY CULTURES AND SUSTAINABILITY IN BIOFUEL PRODUCTION

Energy cultures are emerging as viable renewable energy sources because they satisfy sustainability requirements. The present study involves a survey regarding the technological characteristics for sugarcane and sweet sorghum energy crops, in addition to their potential for bioethanol production. An exploratory survey was conducted regarding the agronomic and technological characteristics of cane and sorghum. Pre-inmates were produced with YPSAC 5% liquid medium, sterilized and 0.10 grams of yeasts FT858 and Pedra-2 were inoculated and incubated at 30 °C for 10 h at 250 rpm. After the production, the cells were recovered by centrifugation, at 105 rpm, resulting in a 10 mg mg-1 concentration of moist dough. This dough was subsequently inoculated in the fermentative medium consisting of a base of sorghum broth and cane without pH correction with a 22 °Brix. Ethanol was analysed by gas chromatography and amino acids by high-efficiency liquid chromatography. Sorghum broth presented a greater availability of serine, arginine, alanine, threonine, and tryptophan amino acids. Yeast hers presented fermentative efficiency for both substrates, but the largest ethanol production occurred in sorghum broth. The results demonstrated that sugar sorghum may be used for energy purposes.

Can Resveratrol Supplementation Reduce Uremic Toxin Plasma Levels From the Gut Microbiota in Nondialyzed Patients With Chronic Kidney Disease?

Uremic toxins such as indoxyl sulfate (IS), p-cresyl sulfate (pCS), and indole-3-acetic acid (IAA) produced by the gut microbiota are recognized as risk factors for many comorbidities, including cardiovascular diseases. Patients with chronic kidney disease (CKD) have an accumulation of these toxins, and nutritional strategies have been proposed to mitigate gut dysbiosis and, consequently, reduce these toxins. This study aimed to evaluate the effects of resveratrol supplementation on the plasma levels of IS, pCS, and IAA in nondialyzed patients with CKD. In this placebo-controlled crossover study, twenty nondialyzed patients were randomly divided into two groups: they received either one capsule/day containing 500mg of trans-resveratrol (63±7.5years, glomerular filtration rate [GFR]: 34±14mL/min, body mass index: 26.8±5.6kg/m2) or a placebo containing 500mg wheat flour (62±8.4years, GFR: 34±13mL/min, body mass index: 28.6±4.4kg/m2) during 4weeks. After 8weeks of washout (no supplementation), another 4weeks of supplementation with crossover was initiated. IS, IAA, and pCS plasma levels were quantified by the reverse phase high-efficiency liquid chromatography method with fluorescent detection. The mRNA expression of nuclear factor erythroid 2-related factor 2 and nuclear factor kappa B in peripheral blood mononuclear cells was evaluated by polymerase chain reaction. C-reactive protein plasma levels were also evaluated. As expected, the uremic toxin levels were negatively correlated with the GFR, but no effect of trans-resveratrol supplementation was found on levels of IS, IAA, and pCS. There was a positive correlation between IS and nuclear factor erythroid 2-related factor 2 (r=0.24, P=.03) and also between IS and C-reactive protein (r=0.21, P=.05). Supplementation with trans-resveratrol did not reduce the plasma levels of IS, pCS, and IAA in nondialyzed patients with CKD. The interactions among uremic toxins and anti-inflammatory and proinflammatory pathways deserve more studies.

Development of a Diagnostic Approach Based on the Detection of Post-Translation Modifications of Fibrinogen Associated with Oxidative Stress by the Method of High Efficiency Liquid Chromatography

Development of a Diagnostic Approach Based on the Detection of Post-Translation Modifications of Fibrinogen Associated with Oxidative Stress by the Method of High Efficiency Liquid Chromatography

Use of Caffeine for the Evaluation of the Anthropic Influence over the Upper and Middle Iguaçu River Basins

Many parameters are usually used as gauges to describe water quality worldwide, such as the concentrations of phosphorus, forms of nitrogen, dissolved oxygen (DO), among others. Though legislative limits for the concentrations of these substances are in place, such is not the case for caffeine. Caffeine is a pharmacologically active alkaloid, from the xanthine group, which can be used as a chemical tracer for anthropic influence over water resources. The objective of this study was to analyze the pollution indicators over the Igua?u River, one of the main rivers in Southern Brazil, through the examination of nutrients, DO and their correlations to caffeine. The water samples were collected from 10 sampling sites along the river course, unevenly spaced to better represent the different environmental scenarios present in its basin, extracted from 2014 to 2017. Caffeine was detected and quantified through high-efficiency liquid state chromatography. Results show that both nutrient and caffeine concentrations increased in intensely urbanized areas, specially from IG2 to IG5 sampling sites. Downstream from IG6 the contaminant concentrations decreased mainly due to higher river flows and lower population density. Caffeine was detected in 82% of the samples, indicating that most of the sampling sites were under anthropic influence.

Estabilidade do cloridrato de vancomicina empregado em soluções de selo antimicrobiano de cateteres intravenosos centrais

Abstract Objective: to verify the stability of vancomycin hydrochloride in antimicrobial seal solutions with and without association of heparin sodium according to temperature and association time. Method: an experimental study designed for the analysis of hydrogenionic potential and concentration by means of high-efficiency liquid chromatography of vancomycin hydrochloride (n=06) and vancomycin hydrochloride and heparin sodium (n=06). The solutions studied were submitted to absence of light, as well as to 22°C and 37°C. Analyses in triplicate (n=192) were performed at the initial moment (T0) and three (T3), eight (T8) and 24 hours (T24) after preparation. The data were submitted to analysis of variance (p≤0.05). Results: concentration of the antimicrobial at 22°C presented a reduction (T0-T8) and a subsequent increase (T24); hydrogenionic potential decreased significantly over time. At 37°C, the concentration increased up to T3 and decreased at T24, with a reduction of hydrogenionic potential up to 24 hours. Concentration of the vancomycin hydrochloride and heparin sodium solutions varied with a reduction at 22°C, accompanied by increased hydrogenionic potential. Precipitate formation was observed by visual inspection of the vancomycin hydrochloride-heparin sodium association (T3). Conclusion: pharmacological stability of vancomycin hydrochloride (5 mg/mL) and physical incompatibility with heparin sodium (100 IU/mL) were evidenced after three hours of association in the antimicrobial seal solutions studied.

Stability of vancomycin hydrochloride employed in antimicrobial seal solutions of central intravenous catheters.

to verify the stability of vancomycin hydrochloride in antimicrobial seal solutions with and without association of heparin sodium according to temperature and association time. an experimental study designed for the analysis of hydrogenionic potential and concentration by means of high-efficiency liquid chromatography of vancomycin hydrochloride (n=06) and vancomycin hydrochloride and heparin sodium (n=06). The solutions studied were submitted to absence of light, as well as to 22°C and 37°C. Analyses in triplicate (n=192) were performed at the initial moment (T0) and three (T3), eight (T8) and 24 hours (T24) after preparation. The data were submitted to analysis of variance (p≤0.05). concentration of the antimicrobial at 22°C presented a reduction (T0-T8) and a subsequent increase (T24); hydrogenionic potential decreased significantly over time. At 37°C, the concentration increased up to T3 and decreased at T24, with a reduction of hydrogenionic potential up to 24 hours. Concentration of the vancomycin hydrochloride and heparin sodium solutions varied with a reduction at 22°C, accompanied by increased hydrogenionic potential. Precipitate formation was observed by visual inspection of the vancomycin hydrochloride-heparin sodium association (T3). pharmacological stability of vancomycin hydrochloride (5 mg/mL) and physical incompatibility with heparin sodium (100 IU/mL) were evidenced after three hours of association in the antimicrobial seal solutions studied.