Solventless-mixing particle coating using a high shear mixer for preparing coated pellets using dry methyl methacrylate and diethylaminoethyl methacrylate copolymer latex

Abstract

The aim of this study was to investigate the feasibility of coated pellet formulation by high shear mixing of drug pellets and polymer particles without solvent or heat. First, drug-layered pellets were prepared by high shear mixing of drug crystals and sugar-cellulose pellets. Second, aqueous methyl methacrylate and diethylaminoethyl methacrylate copolymer latex was solidified by freeze drying to produce dry latex comprising colloidal polymer.

Highlights

• Solventless coating could be achieved by high shear mixing of drug pellets and polymer particles.
• Polymer particles with fragile characteristics exhibited high coating performance.
• Promoting the pulverization of polymer particles enhanced their coating efficiency.
• Coated pellets obtained were annealed at 80 °C for 6 h and suppressed initial drug release.
• Dissolution characteristics were controllable due to the thickness of coated layers.

Finally, the resulting pellets and latex were exposed to high shear mixing, and the obtained coated pellets were characterized. The freeze-dried latex exhibited high coating performance due to its fragile characteristics, which were due to the lack of close contacts between the colloids. This latex was easily pulverized by high shear mixing with the pellets, and the resulting fragments were then deposited on the surface of the pellets.

We examined additional coatings: after high shear mixing of the drug-layered pellets and latex particles, fresh latex was added and mixed with the coated pellets. This process provided coated pellets with thick and dense polymer layers, which could suppress initial drug release after annealed at 80 °C for 6 h. The dissolution was dependent on the coating thickness, which was determined by controlling the amount of coated polymer.

Download the full article as PDF here Solventless-mixing particle coating using a high shear mixer for preparing coated pellets using dry methyl methacrylate and diethylaminoethyl methacrylate copolymer latex

or read it here

Materials

Acetaminophen (AAP) (Tokyo Chemical Industry Co., Ltd., Tokyo, Japan) was used as the model drug. Sugar-cellulose pellets (SCP) (NONPAREIL-105, size fraction: 106–212 μm, Freund Corporation, Tokyo, Japan) were used as core particles and hydrophilic fumed silica (SiO2) (AEROSIL200, Nippon Aerosil Co., Ltd., Tokyo, Japan) was used as a glidant. Aqueous latex (AL) of methyl methacrylate and diethylaminoethyl methacrylate copolymer (Kol) (Kollicoat Smartseal 30D, BASF Japan Ltd., Tokyo, Japan) and commercially available particles of Kol (Kollicoat Smartseal 100P, BASF Japan Ltd., Tokyo, Japan) were used as coating materials. The polymer exhibits gastrosoluble characteristics and is available for immediate release and taste masking. Other chemicals and solvents were analytical reagent grade (purity: >99.5 %).

Keita Kondo, Shoko Mata, Toshiyuki Niwa, Solventless-mixing particle coating using a high shear mixer for preparing coated pellets using dry methyl methacrylate and diethylaminoethyl methacrylate copolymer latex, Advanced Powder Technology, Volume 36, Issue 4, 2025, 104829, ISSN 0921-8831, https://doi.org/10.1016/j.apt.2025.104829.

Read also our interesting article on TaBlitz:

TaBlitz: A new tablet design software that strives for patient centric drug product design

DIRECT CONTACT TO TABLITZ