title: Compaction assay: a rapid and simple in vitro method to assess the responsiveness of a biopolymer matrix to enzymatic modification.
abstract: A rapid and simple in vitro method is described which measures the extent of unrecoiled solids compression when a complex biopolymer is subjected to a centrifugal force. This method, termed the compaction assay, was used to assess the response of purulent cystic fibrosis (CF) sputum samples to the addition of recombinant human deoxyribonuclease I (rhDNase). Enzyme treatment resulted in a dramatic decrease in DNA size, a redistribution of total DNA content from the pellet to supernatant, a significant decrease in that pellet volume and a decrease in elastic modulus. Sample elasticity, measured by a dynamic cone and plate viscometer, could be related to compaction assay results. These results suggest that the compaction assay may be a useful in vitro method for rapidly assessing the actions of enzymatic disruption of a complex biopolymer, such as that observed for the actions of rhDNase on purulent airway secretions.
mesh_terms: D001672:Biocompatible Materials / Q000592:standards; D001696:Biomechanical Phenomena; D001704:Biopolymers; D003001:Cloning, Molecular; D003550:Cystic Fibrosis / Q000201:enzymology / Q000473:pathology*; D004247:DNA / Q000378:metabolism; D003850:Deoxyribonuclease I / Q000235:genetics / Q000494:pharmacology*; D004587:Electrophoresis, Agar Gel; D006801:Humans; D066298:In Vitro Techniques; D008970:Molecular Weight; D011994:Recombinant Proteins / Q000235:genetics / Q000494:pharmacology; D012212:Rheology; D013183:Sputum / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D014783:Viscosity
chemical_list: D001672:Biocompatible Materials; D001704:Biopolymers; D011994:Recombinant Proteins; D004247:DNA; D003850:Deoxyribonuclease I