LEVETIRACETAM IN PLASMA BY UV – CODE Z04310 INTRODUCTION
Treatment of the epileptic patients requires a multidisciplinary medical knowledge, regarding i.e.
pharmacology, psychology and social science. In this contest the various antiepileptic drugs
(AEDs) are used to decrease the frequency and/or severity of seizures in people with epilepsy.
Monitoring of plasmatic concentrations of AEDs is important to improve patient’s theraphy.
Our method allows to determine in the same HPLC run the sieric and/or plasmatic concentration of
EUREKA srl – LAB DIVISION Head Quarter: VAT N° 01547310423 Via Enrico Fermi 25 E-mail:info@eurekaone.com 60033 Chiaravalle (AN) ITALY www.eurekaone.com Tel. +39 071 7450790 Fax + 39071 7496579 This product fulfills all the requirements of Directive 98/79/EC on in vitro diagnostic medical devices (IVD). The declaration of conformity is available upon request. Rev. N° 008 Lavetiracetam in plasma by UV March 2010 TECHNICAL FEATURES Principle of the Method : Levetiracetam is separated treating the serum/plasma with a suitable precipitant. After addition of a stabilization Reagent the solution is directly injected into HPLC. Recovery : Sensitivity : Dynamic Range of the Method :
0,2 – 200 µg/ml
Therapeutic Range in Plasma : Components of the kit :
All the components are ready-to-use. Stability: 3 years at 2–8 °C. The Calibrator is stable 24 months at 2–8°C. Reagent A – Deproteinization Sol. with Internal Standard, 1 x 20 ml Reagent B – Stabilization Solution, 1 x 20 ml Reagent C – Test Solution, 1 x 5 ml Reagent D – Plasma Calibrator lyophil., 1 x 1 ml See Warnings Reagent M – Mobile Phase, 2 x 500 ml Minimum Instrumental equipment required:
Isocratic HPLC System with loop of 50 µl Spectrophotometric Detector UV λ=205 nm Chromatograms Recorder Optional Equipment: Whole Blood Collection Procedure:
Collect 3 ml of blood in a suitable test tube without gel and with anticoagulant Heparin. Centrifuge at 4000 rpm for 5 minutes. Separate the serum and store at – 20 °C. Stable 4 weeks.
PREANALYTICAL PROCEDURE Pipette in a tube :
• 50 µl of Reagent C - Test Solution
INJECTION :
• Inject 50 µl of this solution in the chromatographic system.
Verify that the Test Solution has retention time similar to fig. 1. If the Test is all right you can start with the analytical procedure; if not, check the functionality of the analytical system.
Important : Don’t use this solution to calibrate! ANALYTICAL PROCEDURE STEP 1 : Samples Preparation Pipette in a suitable tube with cap : Calibrator Water HPLC grade Reagent D - Calibrator Reagent A – Deproteinization with Warning: deproteinize directly on Vortex for at least 10 seconds STEP 2: Centrifuge at 5000 rpm for 5 min. STEP 3 : Pipette in a tube 200 µl of clear surnatant. • Add 200 µl of Reagent B – Stabilization Sol.
Vortex for 10 seconds N.B.: at this step, the sample is stable 3 days at 2-8 °C
INJECTION :
• Inject 50 µl of this solution in the chromatographic system. Rev. N° 008 Lavetiracetam in plasma by UV March 2010 LEVETIRACETAM - Warnings REAGENT C: TEST SOLUTION
LEVETIRACETAM Use and Reconstitution: Calibrators are used for calibration of the HPLC system. This lyophilised calibrator has to be prepared like a patient sample. Add exactly 1.0 ml HPLC water to the vial and mix for 15 min. When all material is dissolved, the solution is ready to use. Stability: 24 months if stored at 2-8 °C. After reconstitution the stability of the analytes is at least 15 days at +4°C and at least 3 months at -20° C. Don’t use after expiry date. Packaging : 1 x 1 ml Warning: The calibrator derives from human plasma, so it could be potentially infected. It must be handled with care. SPECTROPHOTOMETRIC DETECTOR PARAMETERS
INTEGRATION TIME HPLC COLUMN PROTECTION
To save the analytical column Reverse Phase GENESIS 4,6 x 150 mm, 4 µ, the use of Metasaver Precolumn Filter 0.5 um (1 x 10 pcs.) cod. ZA6005 is obligatory.
HPLC COLUMN CONDITIONING
Install a new analytical C18 Reversed-Phase column (GENESIS 150 mm x 4,6 mm, 4 µ).
Disconnect the detector and filter 30 ml of H2O: Methanol (20 : 80 v/v) solution and subsequently
30 ml of H2O per HPLC, set flow at 1,2 ml / min. Don’t recycle the washing solutions. Filter the
mobile phase with a vacuum system and a suitable filter of 0,22 µ. Condition the column with the mobile phase at a flow of 1,2 ml / min and discharge the first 30 ml. Condition further on the column for 30 min. also at recycling phase. Finally inject the Chemical Standard and verify the quality of the HPLC run. It is possible to make analysis at recycling phase, providing that you filter the same mobile phase with a filter of 0,22 µ before any analytical run. If room temperature is > 20 °C store the Mobile Phase at 2-8 °C between an analytical session and another.
COLUMN CLEANING
Disconnect ESA detector. Flux 30 ml of H2O and discharge. Flux a solution made of H2O :
Methanol or Acetonitrile (20 : 80 v/v) for 30 min and discharge. When you re-use the column, flux 30 ml of H2O before a new conditioning with the Mobile Phase.
HPLC PARAMETERS
PRESSURE INTEGRATOR HP – 3394 / 3395 / 3396 PARAMETERS
ATTENUATION OPERATIONAL COMPUTER PARAMETERS
IN CONFORMITY WITH THE SPECIFICATION OF OPERATIONAL COMPUTER SOFTWARE
ACCESSORIES AND CONSUMABLES
CODE DESCRIPTION PACKAGING
Control for Levetiracetam in plasma – Level 1
Control for Levetiracetam in plasma – Level 2
Control for Levetiracetam in plasma – Levels 1 and 2
ZFM15960E
Genesis C 18 (150 x 4,6mm -4 um) Analytical Column
Clear glass vials with reduced volume from 1,5 ml to 15 ul +
Fig. 1 : Test Solution Fig. 2 : Plasma Calibrator lyophil. Fig. 3 : Plasma Control lyophil. Level 2 Fig. 4 : Enriched Plasma Sample
LICHEN PLANUS Il líchen planus è una malattia mucocutanea di origine ímmunítaria che colpisce circa l'1% della po-polazione generale. La prevalenza delle manifestazioni orali varia tra lo 0, 1 e il 2,2%. Si osserva prevalentemente in soggetti di sesso femminile (rapporto uomini/donne 2:3) in varie fasce di età a partire dai 20 anni e con una maggiore prevalenza tra i 50 e i 70 anni.
No interaction between rivaroxaban – a novel, oral, direct Factor Xa inhibitor – and atorvastatin Dagmar Kubitza1, Wolfgang Mueck1, Michael Becka2 1Clinical Pharmacology, 2Department of Biometry, Pharmacometry, Bayer HealthCare AG, Wuppertal, Germany Introduction Rivaroxaban is an oral, once-daily, direct Factor Xa (FXa) inhibitor in advanced clinical development for the preve