Construction and characterization of thiolated chitosan coated TPGSylated nanodiamonds for oral delivery of curcumin Page No: 1095-1105

By: Dandan Liu, Zhiyuan Yang, Yue Lu, Weiwei Yang

Keywords: TPGSylated nanodiamonds; thiolated chitosan; oral drug delivery; curcumin

DOI : 10.36721/PJPS.2025.38.3.REG.13223.1

Abstract: Low water solubility and poor intestinal permeability hinder the oral absorption of curcumin (CUR). To address this, we designed a core-shell structured nanoparticle based on nanodiamonds (NDs) and thiolated chitosan (TCS). First, D-?-tocopherol polyethylene glycol 1000 succinate (TPGS) covalently modified NDs were prepared and loaded with CUR (CUR@NDs-TPGS). N-acetylcysteine (NAC) was then coupled to chitosan (CS) to obtain positively charged CS-NAC, which electrostatically coated the negatively charged NDs-TPGS/CUR. Particle size (PS), zeta potential (ZP) and drug loading efficiency (DLE) were selected as screening indices to optimize the formulation and preparation process of CUR@NDs-TPGS/CS-NAC via single-factor experiments. The results showed that after coating with CS-NAC, the PS of optimized CUR@NDs-TPGS/CS-NAC increased from 183.63±5.24 nm to 245.24±3.95 nm, the ZP value flipped from -25.47±1.36 to +25.81±1.06 and the DLE value decreased slightly. Moreover, the nanoparticles adopted a spherical morphology and the cumulative release percentage of the nanocomplexes within 24 h decreased from 35.69% to 25.54% after coating. CUR@NDs-TPGS/CS-NAC remained stable within 48 h in simulated intestinal fluid. Mucin adsorption, GI retention and oral absorption of CUR@NDs-TPGS/CS-NAC were further enhanced compared to CUR@NDs-TPGS. These findings suggest that CUR@NDs-TPGS/CS-NAC is a promising carrier for oral delivery of CUR.



[View Complete Article]