title: Skin sample preparation by collagenase digestion for diclofenac quantification using LC-MS/MS after topical application.
abstract: BACKGROUND
  Skin is the target site to evaluate the pharmacokinetic parameters of topical applications. Sample preparation is one of the influential steps in the bioanalysis of drugs in the skin. Evaluation of dermatopharmacokinetics at preclinical stage is challenging due to lack of proper sample preparation method. There is a need for an efficient sample preparation procedure for quantification of drugs in the skin using LC-MS/MS.
  
  
  RESULTS
  The skin samples treated with collagenase followed by homogenization using a bead beater represents a best-fit method resulting in uniform homogenate for reproducible results.
  
  
  CONCLUSIONS
  A new approach involving enzymatic treatment and mechanical homogenization techniques were evaluated for efficient sample preparation of skin samples in the bioanalysis.
authors.affiliation: Biopharmaceuticals Research, Suven Life Sciences Ltd, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500034, India.
authors.forename: Ramakrishna
authors.initials: R
authors.lastname: Nirogi
authors.affiliation: Biopharmaceuticals Research, Suven Life Sciences Ltd, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500034, India.
authors.forename: Naga Surya Prakash
authors.initials: NS
authors.lastname: Padala
authors.affiliation: Biopharmaceuticals Research, Suven Life Sciences Ltd, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500034, India.
authors.forename: Rajesh Kumar
authors.initials: RK
authors.lastname: Boggavarapu
authors.affiliation: Biopharmaceuticals Research, Suven Life Sciences Ltd, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500034, India.
authors.forename: Ilayaraja
authors.initials: I
authors.lastname: Kalaikadhiban
authors.affiliation: Biopharmaceuticals Research, Suven Life Sciences Ltd, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500034, India.
authors.forename: Devender Reddy
authors.initials: DR
authors.lastname: Ajjala
authors.affiliation: Biopharmaceuticals Research, Suven Life Sciences Ltd, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500034, India.
authors.forename: Gopinadh
authors.initials: G
authors.lastname: Bhyrapuneni
authors.affiliation: Biopharmaceuticals Research, Suven Life Sciences Ltd, Serene Chambers, Road-5, Avenue-7, Banjara Hills, Hyderabad 500034, India.
authors.forename: Nageswara Rao
authors.initials: NR
authors.lastname: Muddana
mesh_terms: D000287:Administration, Topical; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000493:pharmacokinetics*; D002853:Chromatography, Liquid / Q000379:methods; D017364:Collagenases / Q000378:metabolism*; D004008:Diclofenac / Q000008:administration & dosage / Q000493:pharmacokinetics*; D008297:Male; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000378:metabolism*; D012869:Skin Absorption; D013048:Specimen Handling / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D004008:Diclofenac; D017364:Collagenases
keywords: LC–MS; NSAIDs; bead lysis; collagenase; collagenase digestion; dermal PK; enzymatic digestion; skin; skin sample bioanalysis; ultrasonic homogenization