title: Development of lidocaine-coated microneedle product for rapid, safe, and prolonged local analgesic action.
abstract: OBJECTIVE
  To demonstrate rapid (~1 min) lidocaine delivery using 3M's solid microstructured transdermal system (sMTS) for prolonged, local analgesic action.
  
  
  METHODS
  Polymeric microneedles were fabricated via injection molding and then dip-coated using an aqueous lidocaine formulation. The amount of lidocaine coated onto the microneedles was determined by high performance liquid chromatography (HPLC). To assess drug delivery and dermal pharmacokinetics, lidocaine-coated microneedles were inserted into domestic swine. Skin punch biopsies were collected and analyzed to determine lidocaine concentration in skin using HPLC-mass spectrometry (LC-MS). Commercial lidocaine/prilocaine EMLA (Eutectic Mixture of Local Anesthetic) cream was used as comparative control.
  
  
  RESULTS
  Lidocaine dissolves rapidly off the microneedles and into skin such that the 1-min wear time achieves or exceeds lidocaine tissue levels needed to cause analgesia. This therapeutic threshold (100 ng/mg) was estimated by measuring the total amount of lidocaine and prilocaine in skin following a 1 h EMLA application. When co-formulated with 0.03 wt% vasoconstrictor-epinephrine, the concentration of lidocaine in tissue was maintained above 100 ng/mg for approximately 90 min.
  
  
  CONCLUSIONS
  3M's sMTS can be used to provide rapid delivery of lidocaine for local analgesia up to 90 min.
authors: 3M Drug Delivery Systems Division, St. Paul, Minnesota 55144, USA.
authors: Ying
authors: Y
authors: Zhang
authors: Ken
authors: K
authors: Brown
authors: Kris
authors: K
authors: Siebenaler
authors: Amy
authors: A
authors: Determan
authors: Daniel
authors: D
authors: Dohmeier
authors: Kris
authors: K
authors: Hansen
mesh_terms: D000279:Administration, Cutaneous; D000772:Anesthesia, Local; D019162:Anesthetics, Combined / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000818:Animals; D016503:Drug Delivery Systems; D004355:Drug Stability; D004837:Epinephrine / Q000008:administration & dosage / Q000493:pharmacokinetics; D005260:Female; D008012:Lidocaine / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000077442:Lidocaine, Prilocaine Drug Combination; D009339:Needles; D011318:Prilocaine / Q000008:administration & dosage / Q000493:pharmacokinetics*; D012867:Skin / Q000378:metabolism; D013552:Swine; D013997:Time Factors
chemical_list: D019162:Anesthetics, Combined; D000779:Anesthetics, Local; D000077442:Lidocaine, Prilocaine Drug Combination; D011318:Prilocaine; D008012:Lidocaine; D004837:Epinephrine