Measurement of Vancomycin in Renally Impaired Patient Samples Using a New High-Performance Liquid Chromatography Method with Vitamin B12 Internal Standard

Hu, Mae W.; Anne, Lakshmi; Forni, Theresa; Gottwald, Ken

doi:10.1097/00007691-199011000-00009

Cited by 56 publications

(32 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Samples were stored at -70°C until they were assayed. Vancomycin was assayed by a highperformance liquid chromatography method (13), modified for use with MHB. The samples were prepared by precipitation of 0.5 ml of vancomycin per culture with 0.25 ml of propan-2-ol and 0.25 ml of acetonitrile and then centrifuged at 2,500 rpm for 20 min (Heraeus Labofuge GL).…”

mentioning

confidence: 99%

Efficacies of different vancomycin dosing regimens against Staphylococcus aureus determined with a dynamic in vitro model

Duffull

Begg

Chambers

et al. 1994

Antimicrob Agents Chemother

View full text Add to dashboard Cite

A dynamic in vitro model was used to assess four different vancomycin dosing regimens against Staphylococcus aureus. These regimens achieved peak drug concentrations of 48 ,ug/mI (single dose) and 30 ,ug/ml (dosed every 12 h) and constant concentrations of 16 and 8 ,ig/ml. Analysis of the area under the bacterial concentration-time curve, area under the first moment of the bacterial concentration-time curve, and bacterial elimination rate constant showed no difference in the rate or extent of bacterial killing. The optimal dosing method may be that which achieves the lowest area under the curve while concentrations are maintained above the MBC. (14)(15)(16)(17)20). Similarly, most in vitro experiments using fixed concentrations of vancomycin have not demonstrated concentrationdependent killing of various microorganisms (1,18,19). These studies suggest that the best dosing strategy would be to maintain the total area under the concentration-time curve (AUC) as small as possible to reduce dose-related toxicity while still maintaining adequate efficacy.In this study we assessed the efficacy of vancomycin against Staphylococcus aureus over a 24-h period in a dynamic in vitro model using a variety of dosing regimens, including some that are common in clinical practice. These experiments were designed to compare the efficacies of three different dosing schedules with the same AUC and a schedule with a smaller AUC.The dynamic in vitro model used in this experiment has been described previously (3)(4)(5) 37°C. At time zero a bolus of vancomycin (Sigma Laboratories; lot 20H0377) was added to each central chamber to achieve the desired initial concentration. A personal computer controlled two series of pumps with a purpose-developed computer program. The first series of pumps were syringe pumps which infused broth to dilute the contents of each central chamber at a predetermined rate, resulting in a desired exponential decline of vancomycin concentrations (with a half-life of 6 h). The second series were peristaltic pumps which returned the volume of the central chamber to its original level by removing the excess volume each hour. This excess provided a sample which was used to count the number of viable CFU per milliliter. The MIC was estimated prior to the study and following exposure to vancomycin and was 0.75 ,ug/ml by the standard dilution tube technique, with an inoculum size of 2.3 x 105 CFU/ml. The test strain used for the experiments was incubated in MHB overnight and diluted 2.5 h before the experiment to produce an inoculum of _107 CFU/ml in log-phase growth.The study assessed the following vancomycin regimens: (i) a peak concentration of 48 ,ug/ml and a trough of 3 ,ug/ml at 24 h (AUC from 0 to 24 h [AUCO24] = 389 ,ug -h -ml-'); (ii) a peak concentration of 30 ,ug/ml and a trough of 7.5 ,ug/ml at 12 h, dose repeated at 12 h (AUCO24 = 389 ,ug* h * ml-1); (iii) a constant concentration of 16.2 ,ug/ml, representing a 24-h infusion (AUCO024 = 389 ,ug h ml-1); and (iv) a constant concentration of 8 ,ug/ml, repres...

show abstract

mentioning

confidence: 99%

Efficacies of different vancomycin dosing regimens against Staphylococcus aureus determined with a dynamic in vitro model

Duffull

Begg

Chambers

et al. 1994

Antimicrob Agents Chemother

View full text Add to dashboard Cite

show abstract

“…This is a sensitive but expensive technique [6][7][8][9][10][11][12]. Reversed-phase HPLC, a frequently used method to determine drug levels in body fluids, relies on the interaction of the study molecules with the two phases -the mobile and the stationary phase (the column).…”

Section: Discussionmentioning

confidence: 99%

“…This method requires fluorescent-labeled drug and the specific antibody kit against the study drug. Though quite sensitive, FPIA is expensive [9][10][11][12].…”

Section: Introductionmentioning

confidence: 99%

Modified High-Performance Liquid Chromatography Technique for Detection of Vancomycin in Human Vitreous

Raju

Thiagarajan²,

Das³

2004

Ophthalmic Res

View full text Add to dashboard Cite

Purpose: To standardize the technique and methodology for estimating the level of vancomycin in human vitreous using a modified high-performance liquid chromatographic method. Methods: Sample preparation involved spiking the vitreous with known quantities of the drug followed by a brief treatment with 30% trichloroacetic acid. Samples were analyzed on a C18 reverse-phase column using a mobile phase of 50 mM phosphate buffer (pH 4.0) and 10% acetonitrile. Results: Vancomycin was detected at 198 nm. It showed a retention time of 2.2 min in the vitreous. A linear increase in the area under the peak corresponding to the drug was observed with increase in concentration of vancomycin in the vitreous. The method was applied to detect the vancomycin levels in vitreous of 5 patients with exogenous endophthalmitis, 24–48 h after intravitreal injection of vancomycin 1 mg/0.1 ml. The mean concentration of vancomycin in these samples was 120.022 ± 59.87 µg/ml (43.859–179.09 µg/ml). The present technique allowed a quantification limit of 1 µg/ml. Conclusion: This technique is suitable to estimate vancomycin levels in human vitreous in a variety of clinical and experimental studies. It has the added advantages of being less expensive, simple and rapid.

show abstract

“…For ceftriaxone the chromogen was linear over the range of 2.0-36 µg/ml. The separation and identification of vancomycin was done by thin-layer chromatography, normal and reverse phases chromatography [21][22][23][24] . Thus we developed a single method for the combined analysis of both drugs, saving time and other resources.…”

Section: Methods Development and Validationmentioning

confidence: 99%

Untitled

Tariq¹,

Siddiqui²,

Kumar³

et al. 2010

ScienceAsia

View full text Add to dashboard Cite

A reverse phase-liquid chromatographic method with UV detection at 280 nm is described for simultaneous determination of ceftriaxone sodium and vancomycin hydrochloride. Chromatographic separation of the two drugs was achieved on a Betasil C-1 column using a mobile phase consisting of a binary mixture of acetonitrile and triethylamine buffer adjusted to pH 3.5 ± 0.1 with orthophosphoric acid in a ratio of 20:80. The liquid chromatographic method developed offers symmetric peak shape, good resolution, and reasonable retention time for both drugs. Linearity, accuracy, and precision were found to be acceptable over the concentration ranges 125-750 ppm for ceftriaxone and 62.5-375 ppm for vancomycin. The liquid chromatographic method was successfully applied to the quality control of formulated products, plasma, and cerebrospinal fluid samples containing ceftriaxone and vancomycin.

show abstract

Measurement of Vancomycin in Renally Impaired Patient Samples Using a New High-Performance Liquid Chromatography Method with Vitamin B12 Internal Standard

Cited by 56 publications

References 0 publications

Efficacies of different vancomycin dosing regimens against Staphylococcus aureus determined with a dynamic in vitro model

Efficacies of different vancomycin dosing regimens against Staphylococcus aureus determined with a dynamic in vitro model

Modified High-Performance Liquid Chromatography Technique for Detection of Vancomycin in Human Vitreous

Untitled

Contact Info

Product

Resources

About