A simple, low-cost and robust capillary zone electrophoresis method with capacitively coupled contactless conductivity detection for the routine determination of four selected penicillins in money-constrained laboratories.

A simple and robust capillary zone electrophoresis method was developed and validated for the determination of amoxicillin and clavulanate, ampicillin, phenoxymethyl penicillin (Pen V) as well as flucloxacillin. Capacitively coupled contactless conductivity detection was employed as detection mode that makes CE a simple and economic tool for money-constrained laboratories. The developed method is straightforward and user-friendly. It offers good sensitivity and sufficient selectivity for the routine assay of the selected penicillins. The repeatabilities were <1.9% RSD for relative peak areas and <1% RSD for migration times for all the analytes. The method showed good linearity (R2  > 0.995) within the 80-120% range of the target concentration (0.5 mg/mL) for each antibiotic. The accuracy of the method, evaluated by standard fortification at three levels, was good for all the analytes. An extended robustness study was performed by varying ±10% of the optimum value of TRIS concentration, l-histidine concentration and temperature in a full factorial design at two levels. This was to evaluate larger than usual variability of factors on the assay value, in order to better cover potential global variance in lab conditions and equipment. Finally, the method was applied for the determination of percent (%) content of all antibiotics in available formulations.

Determination of veterinary penicillin antibiotics by fast high-resolution liquid chromatography and luminescence detection.

A chromatographic method based on the use of a fused-core column and luminescence detection is described for the determination of six penicillin antibiotics used in veterinary practice, namely amoxicillin, ampicillin, penicillin G, oxacillin, cloxacillin and nafcillin. The use of this column provides the separation of these antibiotics with retention times lower than 4.5min. The tris(2,2'-bipyridyl)ruthenium(II) [Ru(bpy)32+] - Ce(IV) system has been used as post-column derivatization reagent, obtaining a luminescence signal (λem 610nm) proportional to the analyte concentration when the system is excited at 450nm. The dynamic ranges of the calibration graphs are 100-10,000ngmL-1 for all the antibiotics assayed and the limits of detection are in the range of 44-51ngmL-1. The precision, established at two concentration levels of each analyte and expressed as the percentage of the relative standard deviation is in the range of 6.9-9.8%. The method has been satisfactorily applied to the analysis of water and pharmaceutical samples, with recoveries ranging from 88.6% to 108.5%.

Penicillin dust exposure and penicillin resistance among pharmaceutical workers in Tehran, Iran.

BACKGROUND: Antimicrobial resistance (AMR) adversely impacts the prevention and treatment of a wide range of infections and is considered as a serious threat to global public health. Occupational-related AMR is a neglected area of research. OBJECTIVE: To assess exposure to penicillin dust, penicillin active materials, and to report the frequency of penicillin resistance among pharmaceutical workers in Tehran, Iran. METHODS: A quasi-experimental study was conducted among workers on a penicillin production line in a pharmaceutical company (n = 60) and workers in a food producing company (n = 60). Data were collected via survey, air sampling, and throat swab. RESULTS: The mean overall concentrations of penicillin dust and penicillin active material were 6.6 and 4.3 mg/m3, respectively, in the pharmaceutical industry. Streptococcus pneumoniae (S. pneumoniae) was detected in 45% (27) individuals in the exposed group, 92.6% of which showed penicillin resistance. Resistance was significantly higher among workers in penicillin production line (p = 0.014). CONCLUSIONS: High level of AMR among workers in penicillin production line is a health risk for the workers as well as society as a whole through the spread of drug resistant micro-organisms.

Simultaneous determination and toxicological assessment of penicillins in different water matrices.

A multi-residue analysis method was developed for the determination of penicillins in wastewater of WWTP, surface water and groundwater in Spain. The procedure involves a solid phase extraction (SPE) and the subsequent analysis by liquid chromatography coupled to tandem mass spectrometry detection (LC-QqQ-MS/MS). The SPE processes were optimized by test of cartridges, sample pH and elution solvents. ENV+ cartridge was chosen for the extraction of penicillins from different environmental samples. The best conditions for the extraction efficiency of the targets were observed at sample pH 6, by eluting solvents of methanol and acetonitrile respectively. The method has been validated by calibration curve, corresponding regression coefficient, limit of quantification and recoveries. The results showed that the recoveries of more than 90% were presented in all the compounds, except AMOX and AMPI, which had special amino-group in the molecular structure different with others. The matrix effect was also considered in the experiment and it was concluded that different matrix effect could be found between three kinds of waters, and the low retention of AMOX and AMPI on the cartridges was attributed to the matrices interference. The real sample detection showed that the penicillins degraded fast and only AMOX appeared in the studied environmental samples. The results of toxicology test on two compounds (AMOX and AMPI) showed that bacteria V. fischeri was proved to be relatively insensitive to both targets. The decreasing order of toxicity in three environmental waters for AMOX and AMPI was: wastewater > groundwater > surface water.

Simultaneous determination of sulfonamides, penicillins and coccidiostats in pork by high-performance liquid chromatography-tandem mass spectrometry.

Veterinary drugs are widely and legally used to treat and prevent disease in livestock. However, drugs are also used illegally as growth-promoting agents. To protect the health of consumers, maximum residue limits (MRL) in food of animal origin have been established and are listed in Regulation 37/2010. According to this regulation, more than 300 drugs need to be controlled regularly in laboratories for residues of veterinary drugs. A cost-effective analytical method is very important and explains why the development of multi-residual methods is becoming popular in laboratories. The aim of this work is to describe a simple, rapid and economical high-performance liquid chromatography-tandem mass spectrometry method for the simultaneous identification and quantification of 21 veterinary drugs in pork muscle samples. The sample clean-up procedure is performed with acidified dichloromethane and does not require solid phase extraction. The method is applicable to nine sulfonamides and seven coccidiostats identified within 36 min. Calculated relevant validation parameters such as recoveries (from 72.to 126 %), intra-precision and intermediate precision (relative standard deviation below 40 %) and decision limits (below 7 µg Kg(-1)) were within acceptable range and in compliance with the requirements of Commission Decision 2002/657/EC.

Comparación de la biodisponibilidad de un producto test conteniendo sultamicilia comprimidos de 375 mg de liberación inmediata de laboratorios Genven (Leti, S. A. V.) contra la sultamicilina de referencia (unasyn ®) tabletas de 375 mg de laboratorios Pfizer, luego de administrar una dosis única en voluntarios sanos / Comparison of the bioavailability of a test product containing sultamicillin tablets of 375 mg immediate release laboratorios Genven (Leti, SAV) against sultamicillin reference (Unasyn ®) 375 mg tablets of Pfizer, after single dose administration in healthy volunteers

El objetivo del estudio es evaluar la biodisponibilidad comparada entre dos formulaciones de liberación inmediata de Sultamicilina 375 mg, luego de una administración única, en un mismo grupo de voluntarios sanos. El estudio se realizó en 12 voluntarios sanos de ambos sexos. Los voluntarios recibieron de acuerdo al esquema asignado por la aleatorización y en dos períodos, una dosis única por vía oral de un comprimido de una formulación conteniendo 375 mg de Sultamicilina de Laboratorios Genven (Leti, S.A.V.), o una tableta del producto de referencia Unasyn®, de Laboratorios Pfizer. La administración se realizó en ayuno de 10 horas de duración y se mantuvo por dos horas después de suministrado el fármaco. Entre ambos períodos se realizó un lavado de tres días. Los voluntarios que recibieron el producto test en el primer período recibieron el producto de referencia y viceversa. Durante cada período del estudio se obtuvieron doce muestras de sangre: antes de la dosis (tiempo cero), a los 20, 40, 60, 80, 100, 120, 150, 180, 240, 300 y 360 minutos. Para ampicilina las variables farmacocinéticas fueron: formulación test Cmax 2.488.52+/-730.65 ng/mL y para ampicilina referencia 2.392,78+/-931,12 ng/mL; para las AUC0-6 fueron de 169.495,82+/-57506,34 ng/mL/h para la formulación test y de 178.688,42+/-85.534,02 ng/mL/h para la formulación de referencia, para la AUC0-∞ los valores resultante fueron 171.230+/-57.601,31 ng/mL/h para la formulación test y de 179.553,73+/-85.966 ng/mL/h para la formulación de referencia. Para el sulbactam las variables farmacocinéticas fueron: formulación test, Cmax: 2.176,66+/-711,57 ng/mL y para la referencia 2.097,70+/-486,17 ng/mL; las AUC0-6 fueron de 175.924,62+/-45.652,94 ng/mL/h para la formulación test y de 186.342,94+/-47.001,80 ng/mL/h para la formulación de referencia, para la AUC0-∞ los valores resultantes...

Objective: Evaluated the comparative bioavailability of two formulations of immediate release 375 mg Sultamicillin after a single administration in the same group of healthy volunteers.Methods: The study was conducted in 12 healthy volunteers of both sexes. The volunteers were assigned according to the randomization scheme and two periods, a single oral dose of one tablet of a formulation containing 375 mg of Sultamicillin Genven (Leti, S.A.V.) Laboratories, or the reference product Unasyn®, Pfizer Laboratories. The administration was carried out in fast of 10 hours and continued for two hours after administeringthe drug. Between the two periods was a washout period of three days. Volunteers who received the test product in the first period will receive the reference product and vice versa. During each period of twelve samples were obtained from blood: pre-dose (time zero) 20, 40, 60, 80, 100, 120, 150, 180, 240, 300 and 360 minutes.Results: For ampicillin pharmacokinetic parameters were Cmax test formulation � 2.488.52+/-730.65 ng/mLand referenceformulation 2.392,78+/-931.12 ng/mL; for AUC0-6 were 169.495,82+/-57.506,34 ng/mL/h for the test formulation and � 178.688,42+/-85.534,02 ng/mL/hfor the reference formulation,for the AUC0-∞ the resulting values were 171.230+/-57.601,31 ng/mL/h for the test formulation and 179.553,73+/-85.966 ng/mL/h for the reference formulation.For sulbactam pharmacokinetic parameters were: Cmax: test 2.176,66+/-711.57 ng/mL and reference 2.097,70+/-486.17 ng/mL; the AUC0-6 were 175.924,62+/-45.652,94 ng/mL/h for the test formulation and 186.342.94+/-47.001,80 ng/mL/h for the reference formulation, for the AUC0-∞ the resultingvalues were 176.900.54+/-45.843,65 ng/mL/hto formulationtest and 187.399,88+/-47.487,22 ng/mL/h for the reference formulation...

Application of ion-exchange cartridge clean-up in food analysis. VI. Determination of six penicillins in bovine tissues by liquid chromatography-electrospray ionization tandem mass spectrometry.

A multiresidue analytical method was developed for the quantification of benzylpenicillin (PCG), phenoxymethylpenicillin (PCV), oxacillin (MPIPC), cloxacillin (MCIPC), nafcillin (NFPC) and dicloxacillin (MDIPC) in bovine tissues using liquid chromatography- electrospray ionization tandem mass spectrometry (LC-ESI MS/MS) with a multiple reaction monitoring technique. Using the deuterated PCG and NFPC as internal standard was effective for improvement of repeatability and accuracy. We chose [M-H-141]- as a monitor ion of MRM analysis and [M-H]- as a precursor ion for each penicillin. Combination of an ion-exchange cartridge clean-up and ion-pair LC enable us to determine the residual penicillins using the standard curves made from standard solutions without the influence of sample matrix on the MS. The average recoveries of PCG, PCV, MPIPC, MCIPC, NFPC and MDIPC from bovine liver, kidney and muscle at the same concentrations as the tolerance levels of PCG (50 microg/kg) ranged from 77 to 101% with the coefficients of variation ranging from 0.7 to 4.2% (n = 5). The limits of quantification for the six penicillins were 2-10 microg/kg in bovine muscle, liver and kidney (S/N ratio >10).

Economic evaluation of risks to producers who use milk residue testing programs.

OBJECTIVE: To evaluate the decision to test for milk antimicrobial residues in milk from dairy cows treated with procaine penicillin G (PPG). DESIGN: Economic-decision analysis after stochastic simulation. SAMPLE POPULATION: 1,000 computer-simulated cows/model. PROCEDURE: Meta-analysis of the Food Animal Residue Avoidance Databank was used to generate PPG disappearance curves for cows given single PPG treatments, IM, of 6,600 U/kg (3,000 U/lb) of body weight or 26,400 U/kg (12,000 U/lb), and multiple treatments at 26,400 U/kg (12,000 U/lb), IM. These curves were entered into 1,000-replication stochastic pharmacokinetic models, generating population-level milk PPG profiles for each treatment group for each day after treatment, which were subjected to economic-decision analyses of feasibility of residue testing. The model was evaluated for changes in herd size, proportion of herd available for testing, milk production, test price, test sensitivity/specificity, and withdrawal periods. RESULTS: For both single-treatment groups, a 2-day withdrawal period avoided violative residues. However, nearly two thirds of the cows risked false identification for violative residues. For the multiple-treated group, nearly 40% had violative residues after a 5-day withdrawal period, and an additional 10 to 15% risked false identification for violative residues. Economic analysis yielded a decision against testing; mean cost was $2 (ie, 5% more than the mean cost of not testing). CLINICAL IMPLICATIONS: Complex dynamics of current milk residue tests discourage practitioners from recommending procedures to clients. In general, increases in herd size, milk production, proportion of a herd available for testing, or milk price will increase the value of testing. Increasing test sensitivity decreases its desirability to producers.

Tentative method for the qualitative detection and quantitative assessment of air contamination by drugs.

A method for detecting and measuring air contamination by drugs is described which uses an electrostatic bacterial air sampler, sprayers for micronizing drugs, and Mueller-Hinton medium seeded with a highly susceptible strain of Sarcina lutea. Three antibiotics (penicillin, tetracycline, aminosidine) and a sulfonamide (sulfapyrazine) were identified by pretreating portions of medium, showing no bacterial growth, with penicillinase or p-aminobenzoic acid solution and subsequently determining how both drug(-) susceptible and drug-resistant strains of Staphylococcus aureus were affected by this pretreatment. Quantitative determinations were also attempted by measuring the size of the inhibition zones.