Innovative color jet 3D printing of levetiracetam personalized paediatric preparations

3D printing is a promising technology used in the fabrication of complex oral dosage delivery pharmaceuticals.This study first reports an innovative color jet 3D printing(CJ-3DP)technology to produce colorful cartoon levetiracetam pediatric preparations with high accuracy and reproducibility.For this study,the ideal printing ink consisted of 40%(v/v)isopropanol aqueous solution containing 0.05%(w/w)polyvinylpyrrolidone and 4%(w/w)glycerin,which was satisfied with scale-up of the production.The external and internal spatial structures of the tablets were designed to control the appearance and release,and cartoon tablets with admirable appearances and immediate release characteristics were printed.The dosage model showed a good linear relationship between the model volume and the tablet strength(r>0.999),which proved the potential of personalized administration.The surface roughness indicated that the appearance of the CJ-3DP tablets was significantly better than the first listed 3D printed drug(Spritam R).Moreover,the scanning electron microscopy and porosity results further showed that the tablets have a structure of loose interior and tight exterior,which could ensure good mechanical properties and rapid dispersion characteristics simultaneously.In conclusion,the innovative CJ-3DP technology can be used to fabricate personalized pediatric preparations for improved compliance.Due to the stable formulation and fabrication process,this technology has the potential in scale-up production.

Electrohydrodynamic direct-writing of conductor–insulator–conductor multi-layer interconnection

A multi-layer interconnection structure is a basic component of electronic devices, and printing of the multi-layer interconnection structure is the key process in printed electronics. In this work, electrohydrodynamic direct-writing （EDW） is utilized to print the conductor-insulator--conductor multi-layer ~nterconne^ction structure. Silver ink is chosen to print the conductor pattern, and a polyvinylpyrrolidone （PVP） solution is util^zed to f^bricate the insulator layer between the bottom and top conductor patterns. The influences of EDW process parameters on the line width of the printed conductor and insulator patterns are studied systematically. The obtained ~es^l~s show that the line width of the printed structure increases with the increase of the flow rate, but decreases with the increase of applied voltage and PVP content in the solution. The average resistivity values of the bottom and top silver conductor tracks are determined to be 1.34 × 10-7 Ω.m and 1.39×10-7 Ω.m, respectively. The printed PVP layer between the two conductor tracks is well insulated, which can meet the insulation requirement of the electronic devices. This study offers an alternative, fast, and cost-effective method of fabricating conductor-insulator-conductor multi-layer interconnections in the electronic industry.

Fabrication of micro/nano-structures by electrohydrodynamic jet technique

Electrohydrodynamicjet （E-Jet） is an approach to the fabrication of micro/nano-structures by the use of electrical forces. In this process, the liquid is subjected to electrical and mechanical forces to form a liquid jet, which is further disintegrated into droplets. The major advantage of the E-Jet technique is that the sizes of the jet formed can be at the nanoscale far smaller than the nozzle size, which can realize high printing resolution with less risk of nozzle blockage. The E-Jet technique, which mainly includes E-Jet deposition and E-Jet printing, has a wide range of applications in the fabrication ofmicro/nano-structures for micro/nano-electromechanical system devices. This tech- nique is also considered a micro/nano-fabrication method with a great potential for commercial use. This study mainly reviews the E-Jet deposition/printing fundamentals, fabrication process, and applications.