Study On 3D Printed Colonic Chlorogenic Acid Capsule Scaffold And Its Controlled Released Behavior

Fused deposition modeling is one of the most common additive manufacturing technologies.In the field of medicine,non-toxic and biodegradable thermoplastic polymers used to print tablets or capsules with various special shapes and accurate internal structures.Tablets or capsules can be prepared with various special shapes and internal accurate structures according to the needs of patients by fused deposition modeling（FDM）3D printing technology,focused on the needs of patients individual differences（age,disease status,metabolism,etc.）,to achieve personalized customization.Drawing on the idea of personalized medicine,3D printing technique has a considerable potential for personalized dietary supplements or health foods.In this paper,polylactic acid（PLA）was used to print 9-channel and 18-channel PLA capsule scaffold structures,and its 3D printing parameters were optimized by artificial neural networks.Chlorogenic acid（CGA）was prepared colon controlled-release capsules,which was the deliver functional factor target of polyphenols.CGA and hydroxypropyl methyl cellulose（HPMC）,pectin/sodium alginate were mixed and injected into the PLA capsule holder.The capsule is sealed with Eudragit water dispersion which could target the colon.The released process and law of CGA are studied in a simulated in vitro digestive environment,providing a new idea for the personalized manufacturing of dietary supplements or health foods.The research conclusions are as follows:（1）The neural network is used to optimize the 3D printing parameters of the PLA capsule scaffold.Research shows that,when the diameter of the printing nozzle diameter was 0.3 mm,and the printing speed ranged between 25 mm/s and 30 mm/s,the printing temperature ranged between 173℃and 180℃,the printing accuracy of 9-channel capsule scaffold structure was better with lower energy consumption and higher printing efficiency.When the diameter of the printing nozzle diameter was 0.3mm,and the printing speed was 20 mm/s,the printing temperature ranged between 170℃and 180℃,the printing accuracy of 18-channel capsule scaffold structure was better.When the manufactured structure was different,the automatic calculation of the structure by the slicing software will affect the path of the entire printing process,causing differences in printing parameters.When the channel side length was expanded to 1.2 mm,the actual measured value of the two capsule scaffold structure MSE is smaller than the predicted value,the optimized printing parameter range is still applicable the enlarged structure.（2）The effects of different sol delivery carriers and targeted sealing materials on the controlled release effect of CGA capsules with two channel structures were studied.Studies have shown that both capsules with two channel structures can achieve colon-targeted controlled released,and the total release rate of CGA exceeds 90%.The controlled released difference between the two sol delivery Carrier is not obvious.The sealing effect and slow down release was better than Eudragit^?S100,and the slow down release ability is stronger.The capsule released process has a high degree of fitting to the Ritger-peppas model（R² are higher than 0.98）,and the main release mechanism was super Case II transport.（3）The released process of CGA capsules with two channel structures,two targeted sealing films and different sol carriers in different simulated media was studied.The results of scanning electron microscope showed that the type of sealing film directly affects the release of CGA.In addition to the sealing film,the capsule structure,the interaction force between the CGA and the sol,and the rheology of the sol are all factors that affect the release of CGA.