title: [Evaluation on gelling properties of shuanghuanglian in situ gel by dynamic rheology].
abstract: OBJECTIVE
  To determine the rheological properties of shuanghuanglian in situ gel (SHL-gel) by using dynamic rheological experiments, in order to evaluate its gelling properties shuanghuanglian in situ gel and predict its gelling behavior in vivo.
  
  
  METHODS
  Rheological parameters were determined by scanning of shear rate and frequency at different temperatures. The phase transition process from liquid to semisolid was described by testing of process heating/cooling and acute heating/cooling.
  
  
  RESULTS
  SHL-gel was Newtonian fluid under the conditions of a phase angle approaching 90 degrees at low temperature or room temperature, with its viscous characteristics dominated. It was shear-thinning pseudoplastic fluid under the conditions of a low phase angle at body temperature, with its elastic characteristics dominated. During the phase transition process, the phase angle delta was getting sharp, with exponential increase of the modulus. The gelling temperature (Tg) was at (35.38 +/- 0.05) degrees C, the phase transition temperature ranged from 33.71 to 37.01%, and phase transition time was 140 s.
  
  
  CONCLUSIONS
  The dynamic rheological experiment characterizes the gelling properties of Shuanghuanglian in situ gel so precisely that it can be used as the basis of for in vitro evaluation and quality control of products.
authors.affiliation: Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China.
authors.forename: Liang-mian
authors.initials: LM
authors.lastname: Chen
authors.forename: Jin-yu
authors.initials: JY
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Tong
authors.forename: Bing-lin
authors.initials: BL
authors.lastname: Zheng
mesh_terms: D004365:Drugs, Chinese Herbal / Q000737:chemistry* / Q000592:standards; D044367:Phase Transition; D011786:Quality Control; D012212:Rheology; D013696:Temperature; D014783:Viscosity
chemical_list: D004365:Drugs, Chinese Herbal; C516400:shuang-huang-lian