RESUMEN
Metal nanoparticles (NPs) with superior physicochemical properties and biocompatibility have shown great potential in theranostics. However, metal NPs show poor stability in some harsh conditions such as strong acid, oxidation, corrosion and high-temperature conditions, which limits their extensive bioapplications. To address such issue, a variety of superstable metal graphitic nanocapsules with the metal cores confined in the nanospace of few-layer graphitic shell have been developed for biodetection and therapy in harsh conditions. In this mini-review, we summarize the recent advances in metal graphitic nanocapsules for bioapplications in harsh conditions. Firstly, their theranostic performance in non-intrinsic physiological harsh environment, including oxidation, corrosion and high-temperature conditions, is systematically discussed. Then, we highlight their theranostic performance in the harsh stomach condition that is strong acidic and pepsin-rich. It is expected that this review will offer inspiration to facilitate the exploitation of novel theranostic agents that are stable in harsh conditions.
RESUMEN
Colorectal cancer (CRC) is a prevalent and fatal cancer. Oral administration provided the potential for in situ treatment of the colorectal cancer. However, drugs couldn't be well-absorbed mainly due to its degradation in the gastric area and poor intestinal permeability. In this study, we synthesized deoxycholic acid and hydroxybutyl decorated chitosan nanoparticles (DAHBC NPs) as oral curcumin (CUR) delivery system for colorectal cancer treatment. DAHBC with lower critical solution temperature (LCST) below 37⯰C (27-33⯰C) was obtained. DAHBC NPs were correspondingly stable in simulated gastric conditions (pHâ¯1.2, 37⯰C), due to the offset of size change between pH-responsive expansion and thermo-responsive shrinkage. In simulated intestinal tract (pHâ¯7.0-7.4, 37⯰C), DAHBC NPs exhibited burst release of CUR owing to the onefold effect of thermo-responsive shrinkage. DAHBC27 NPs showed the minimum CUR leakage (~10%) in simulated gastric conditions, because a furthest temperature-sensitive shrinkage caused by the lowest LCST offset the expansion in acid environment. DAHBC27 NPs induced ~10-fold increased (Pâ¯<â¯0.05) CUR absorption by paracellular transport pathway, compared to the free CUR. Thus, DAHBC NPs stabilized in the gastric environment may be a promising oral drugs delivery system for effective in situ colorectal cancer therapy.