Preparation And Release Kinetics Of Multi-Functional Mothproofing Sustained-release Tablets Based On Eupatorium Powders As A Carrier

The mothproofing sustained-release tablets were prepared by themethod of direct compression using eupatorium powders as a carriermaterial, lavender flavor and empenthrin as active agents, and appropriateabsorbents and additives as formulation percipients.The flavors appropriately incorporated into the tablets wereevaluated by using sniffing method and in vitro release experiment; Theabsorbents appropriately incorporated into the tablets were selected byusing maximum absorption experiment, compression formulationexperiment and in vitro release experiment; The influence of thecompositions of the tablets and formulation conditions on the releasekinetics was investigated using in vitro dynamic release experiments; Theefficacies of eupatorium powders-based mothproofing sustained-release tablets were evaluated using the black carpet beetles as test insects.The results of formulation conditions of the tablets showed that:(1)The incorporation of a certain amount of fragrant agent with the flavorsuch as lavender, jasmine, lemon, osmanthus into the tablets could notonly mask the unpleasant smell of eupatorium powders but also prolongthe release time of flavor from the sustained-release tablets;(2)Micro-silica powders, which had high oil-absorbing ability goodcompressibility and controlled-release effect, were validated as anappropriate absorbent for lavender flavor oil to incorporate into thetablets; The maximum amount of lavender flavor oil absorbed onto theabsorbent of micro-silica powders was up to13%(m/m);(3) The additionof1%(m/m) magnesium stearate into the tablets could significantlyimprove the formulation properties of the tablets and shortening the timeof formulation. Based on the above conclusions, the sustained-releasetablets could be successfully prepared by using eupatorium powderswhich were in the mesh size between120and140as a carrier and theformulation pressure of10MPa. The maximum amount of eupatoriumpowders could reach76%(m/m) of the tablet. The obtained lavenderflavor-containing eupatorium-based tablets had good appearance, and noloosen, cracking, and oil seepage phenomena, and the release of lavenderflavor from the tablets sustained more than3months. The abovepreparation conditions could also be applied to make mikania micrantha powders-based sustained release tablets.The results of the influence of the compositions of the tablets on therelease profiles showed that:(1) The use of micro-silica with differentmesh sizes and different pre-treatment as an absorbent incorporated intothe tablets had no significant effects on the release rates of tablets;(2)The release rates of lavender flavor from the tablets increased with theincrease in the lavender flavor loading when the amount of micro-silicaincorporated in the tablets were kept constant, and decreased with thereduction in the amount of micro-silica when the amount of lavenderflavor oil incorporated into the tablet was constant, also remarkablyreduced with the increasing amount of micro-silica and magnesiumstearate;(3) The release rate of flavor from the tablets prepared by usingleave powders of eupatorium adenophorum was about10%lower thanthat from the tablets prepared by using stem powders of eupatorium, butthe tablets prepared by using eupatorium adenophorum obtained fromdifferent habitats had no significant effects on the release rates of flavorfrom the tablets.The results of FT-IR Spectra showed that there was physicaladsorption between micro-silica and lavender flavor; lavender flavor andempenthrin could be used together because there was no chemicalreaction between lavender flavor and empenthrin.The results of the evaluation of packaging materials for the tablets showed that the three-layer non-woven had best controlled-release effect,and the release rates of flavor from the tablets decreased significantlyafter packaging either under dynamic or static condition. After packaging,the release of the active ingredient in empenthrin/lavender flavor/eupatorium tablets became linear release pattern. The unpleasant smell ofeupatorium powders could be successfully masked when the amount ofdaily release was up to4mg, also the release of lavender flavor from thetablets could be sustained more than3months.The results of efficacy test showed that The fabric damage degreecould be achieved grade≦≦when the mass fraction of lavender flavorand empenthrin were13%(m/m) and0.67%(m/m) respectively in themothproofing sustained-release tablets; The efficacy increased withincreasing amount of empenthrin incorporated into the tablets; Theincorporation of a certain amount of lavender flavor into the tablets couldnot only mask the bad smell of eupatorium dry powders but also improvethe mothproofing efficacy of the tablets.