title: Split calibration curve: an approach to avoid repeat analysis of the samples exceeding ULOQ.
abstract: BACKGROUND
  The current practice of using calibration curves with narrow concentration ranges during bioanalysis of new chemical entities has some limitations and is time consuming. In the present study we describe a split calibration curve approach, where sample dilution and repeat analysis can be avoided without compromising the quality and integrity of the data obtained.
  
  
  RESULTS
  A split calibration curve approach is employed to determine the drug concentration in plasma samples with accuracy and precision over a wide dynamic range of approximately 0.6 to 15,000 ng/ml for dapsone and approximately 1 to 25,000 ng/ml for cyclophosphamide and glipizide. A wide dynamic range of concentrations for these three compounds was used in the current study to construct split calibration curves and was successfully validated for sample analysis in a single run.
  
  
  CONCLUSIONS
  Using this method, repeat analysis of samples can be avoided. This is useful for the bioanalysis of toxicokinetic studies with wide dose ranges and studies where the sample volume is limited.
authors.affiliation: Department of DMPK & Toxicology, Sai Advantium Pharma Ltd, Building 1, Plot 2, Chrysalis Enclave, International Biotech Park, Phase 2, Hinjewadi, Pune, 411057, India. basu.sudipta@gmail.com
authors.forename: Sudipta
authors.initials: S
authors.lastname: Basu
authors.forename: Abdul
authors.initials: A
authors.lastname: Basit
authors.forename: Selvan
authors.initials: S
authors.lastname: Ravindran
authors.forename: Vandana B
authors.initials: VB
authors.lastname: Patel
authors.forename: Subrahmanyam
authors.initials: S
authors.lastname: Vangala
authors.forename: Hitesh
authors.initials: H
authors.lastname: Patel
mesh_terms: D000284:Administration, Oral; D000818:Animals; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000592:standards; D003520:Cyclophosphamide / Q000097:blood* / Q000493:pharmacokinetics / Q000592:standards; D003622:Dapsone / Q000097:blood* / Q000493:pharmacokinetics / Q000592:standards; D005913:Glipizide / Q000097:blood* / Q000493:pharmacokinetics / Q000592:standards; D006207:Half-Life; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D053719:Tandem Mass Spectrometry / Q000592:standards
chemical_list: D003520:Cyclophosphamide; D003622:Dapsone; D005913:Glipizide