Cytotoxicity and drug release behavior of PNIPAM grafted on silica-coated iron oxide nanoparticles

The nanoparticles containing thermosensitive and magnetic properties were investigated for their potential use as a novel drug carrier for targeted and controlled release drug delivery system. These thermosensitive and magnetic nanoparticles were prepared by grafting thermosensitive poly (N-isopropylacrylamide) (PNIPAM) on the surface of silica (SiO₂)-coated Fe₃O₄ nanoparticles with the particle size of 18.8 ± 1.6 nm. Adsorption and desorption behavior of bovine serum albumin (BSA) on the surface of PNIPAM-grafted SiO₂/Fe₃O₄ nanoparticles was studied, and the results indicated that these nanoparticles were able to absorb protein at temperature above the lower critical solution temperature (LCST) and to be desorbed below the LCST. Cytotoxicity studies conducted on Chinese hamster ovary (CHO-K1) cells using methyl tetrazolium (MTT) assays revealed that cell viability of 1 mg/mL PNIPAM-grafted nanoparticles was slightly decreased after 24 h of incubation as compared to the lower concentration of nanoparticles. Furthermore, the concentration of 0.5 mg/mL PNIPAM-grafted nanoparticles was totally biocompatible for 48 h, but had low cytotoxicity after 72 h of incubation. These PNIPAM-grafted nanoparticles did not induce morphological change in their cellularity after exposure for 24 and 108 h. These results demonstrate that PNIPAM-grafted nanoparticles are biocompatible and have potential use as drug carriers.     

Rapid synthesis of SiO<Subscript>2</Subscript> by ultrasonic-assisted Stober method as controlled and pH-sensitive drug delivery

In this paper, the monodisperse silica nanoparticles were prepared by ultrasonic-assisted Stober method, and it explained that the ultrasonic cavitation effect shortened the reaction time from the original hours to f5 min. The effects of ultrasonic time, ultrasonic power, and stirring speed on the morphology, composition, and specific surface area of silica nanoparticles were investigated by field emission electron microscopy (FE-SEM). The results showed that nanoparticles with the best dispersity and the most uniform morphology were obtained under the optimized conditions (ultrasonic time is 5 min, ultrasonic power is 160 W, and the magnetic stirring speed is 999 rpm). The phase composition of SiO₂ was characterized by high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), nano-size/zeta potential analyzer, and Fourier transform infrared spectroscopy (FT-IR). It showed that all typical peaks of samples are in line with the SiO₂ spectrum, the particle size distribution and zeta potential value of the silica is 615?±?35.6 nm and 59.87?±?0.91 mv, respectively, which further verified that the spherical silica nanoparticles with good dispersity can be synthesized in a very short time. Hemolysis test showed that nano-SiO₂ had high blood compatibility and biocompatibility when its concentration was less than 1 mg/mL. Doxorubicin (DOX·HCl) was regarded as a drug model to investigate the drug loading capacity of synthesized SiO₂; the results showed that the drug loading capacity and encapsulation efficiency reached 42.6?±?1.2 and 85.2?±?2.5%, respectively. Furthermore, the drug release experiments fitted well with the Higuichi equation with correlation coefficient (R²) of 0.9984, which further confirmed that the SiO₂/DOX drug delivery system has the controlled release property, and it also displayed pH-responsive behavior (at 96 h, the cumulative release of SiO₂/DOX in PBS solution with pH 7.4, 6.5, and 5.0 was 48.33, 62.31, and 94.86%, respectively). Therefore, this paper provides the possibility for developing more effective, safer, and more targeted controlled drug carriers.     

In vitro digestion of curcuminoid-loaded lipid nanoparticles

Curcuminoid-loaded lipid nanoparticles were produced by melt homogenization. The used lipid matrices were medium chain triglycerides, trimyristin (TM), and tristearin. The mean particle size of the preparations was between 130 and 180?nm. The incorporated curcuminoids revealed a good stability over a period of 12?months. The curcuminoid-loaded lipid nanoparticles were intended for the oral delivery of curcuminoids. Therefore, the fate of the triglyceride matrix in simulated gastric and simulated intestinal media under the influence of pepsin and pancreatin, respectively, was assessed. The degradation of the triglycerides was monitored by the pH?Cstat method and with high performance thin layer chromatography in connection with spectrodensitometry to quantify the different lipid fractions. The TM nanoparticles were not degraded in simulated gastric fluid (SGF), but the decomposition of the triglyceride matrix was rapid in the intestinal media. The digestion process was faster in the simulated fed state medium compared to the simulated fasted state medium. Additionally, the stability of the incorporated drug was tested in the respective physiological media. The curcuminoids showed an overall good stability in the different test media. The release of the curcuminoids from the lipid nanoparticles was determined by fluorescence imaging techniques. A slow release of the drug was found in phosphate buffer. In contrast, a more distinct release of the curcuminoids was verifiable in SGF and in simulated intestinal fluids. Overall, it was considered that the transfer of the drug into the outer media was mainly triggered by the lipid degradation and not by drug release.     

Core–shell-structured nanothermites synthesized by atomic layer deposition

Chitosan was conjugated with folic acid (FA) and the resulting chitosan derivatives with a FA-substitution degree of around 6 % was used to synthesize FA-conjugated chitosan–polylactide (FA–CH–PLA) copolymers to build a drug carrier with active targeting characteristics for the anticancer drug of paclitaxel (PTX). Selected FA–CH–PLAs with various polylactide percentages of about 40 wt% or lower were employed to fabricate nanoparticles using sodium tripolyphosphate as a crosslinker, and different types of nanoparticles were endued with similar average particle-sizes located in a range between 100 and 200 nm. Certain types of PTX-loaded FA–CH–PLA nanoparticles having encapsulation efficiency of around 90 % and initial load of about 12 % were able to release PTX in a controlled manner with significant regulation by polylactide content in FA–CH–PLAs. Targeting characteristic of achieved nanoparticles was confirmed using FA-receptor-expressed MCF-7 breast cancer cells. The uptake of PTX revealed that optimized FA–CH–PLA nanoparticles with an equivalent PTX-dose of around 1 μg/mL could have more than sixfold increasing abilities to facilitate intracellular paclitaxel accumulation in MCF-7 cells after 24 h treatment as compared to free PTX. At a relatively safe equivalent PTX-dose for normal MCF-10A mammary epithelial cells, the obtained results from Hoechst 33342 staining indicated that optimized PTX-loaded FA–CH–PLA nanoparticles had more than threefold increasing abilities to induce MCF-7 cell apoptosis in comparison to free PTX.     

Scalable synthesis of palladium nanoparticle catalysts by atomic layer deposition

Potential applications in drug delivery from nanostructures composed of two oppositely charged polymethacrylates, eudragit^? L100 (EL) and eudragit^? EPO (EE), loaded with three model basic drugs (D), atenolol, propranolol, and metroclopramide were evaluated. The self-organized nanoparticles based on drug-interpolyelectrolyte complexes (DIPEC), (EL-D₅₀)?CEE_X, were obtained by mixing the aqueous dispersions of both polyelectrolytes at room temperature in an ultrasound bath. Dispersions of (EL-D₅₀) neutralized with increasing proportions of EE exhibited a rise of turbidity, particle sizes in the range of 150?C400?nm, and high negative zeta potential. The sign of zeta potential was shifted from negative to positive by changes in composition of DIPEC. Freeze dried DIPEC were easily redispersed in water yielding nearly the same parameters of fresh dispersions. In vitro release experiments using Franz cells showed that DIPEC systems behave as a drug reservoir that slowly releases the drug as water is placed in the receptor compartment. The release rate was raised by ionic exchange with counterions present in simulated physiological fluids placed in the receptor media. Delivery of D from DIPEC exhibited a remarkable robustness toward simulated physiological media of different pH. The DIPEC systems exhibit interesting properties to design nanoparticulate drug delivery systems for oral and/or topical routes.     

Synthesis and characterization of microporous hollow core-shell silica nanoparticles (HCSNs) of tunable thickness for controlled release of doxorubicin

Hollow core-shell silica nanoparticles (HCSNs) are being considered as one of the most favorable drug carriers to accomplish targeted drug delivery. In the present study, we developed a simple two-step method, employing polystyrene (PS) nanoparticles (150?±?20 nm) as a sacrificial template for the synthesis of microporous HCSNs of size 230?±?30 nm. PS core and the wall structure directing agent cetyl trimethyl ammonium bromide (CTAB) were removed by calcination. Monodispersed spherical HCSNs were synthesized by optimising the parameters like water/ethanol volume ratio, PS/tetraethyl orthosilicate (TEOS) weight ratio, concentration of ammonia, and CTAB. Transmission electron microscopy (TEM) revealed the formation of hollow core-shell structure of silica with tunable thickness from 15 to 30 nm while tailoring the concentration of silica precursor. The results obtained from the cumulative release studies of doxorubicin loaded microporous HCSNs demonstrated the dependence of shell thickness on the controlled drug release behavior. HCSNs with highest shell thickness of 30 nm and lowest surface area of 600 m²/g showed delay in the doxorubicin release, proving their application as a drug carrier in targeted drug delivery systems. The novel concept of application of microporous HCSNs of pore size ~?1.3 nm with large specific surface area in the field of drug delivery is successful.     

海藻酸改性的空心Fe3O4纳米颗粒的制备与应用

不使用任何模板一步制得空心Fe₃O₄纳米颗粒,然后将海藻酸钠嫁接在氨基化的空心Fe₃O₄表面,再利用海藻酸盐与钙离子的作用,在空心Fe₃O₄表面形成一个凝胶化层,制得海藻酸盐凝胶化的空心Fe₃O₄纳米颗粒,粒径约为400～500 nm．采用TEM、XRD、XPS、VSM等手段对纳米微球进行表征．VSM表征结果表明在室温下样品磁性材料为超顺磁性．改性Fe₃O₄纳米颗粒成功地用于柔红霉素的载负和缓释,最大载负率和载药量分别为28.4%和14.2%．缓释结果表明,海藻酸盐凝胶化层的存在,能更有效控制柔红霉素缓慢地释放．     

Particle release and control of worker exposure during laboratory-scale synthesis,handling and simulated spills of manufactured nanomaterials in fume hoods

Fume hoods are one of the most common types of equipment applied to reduce the potential of particle exposure in laboratory environments. A number of previous studies have shown particle release during work with nanomaterials under fume hoods. Here, we assessed laboratory workers’ inhalation exposure during synthesis and handling of CuO, TiO₂ and ZnO in a fume hood. In addition, we tested the capacity of a fume hood to prevent particle release to laboratory air during simulated spillage of different powders (silica fume, zirconia TZ-3Y and TiO₂). Airborne particle concentrations were measured in near field, far field, and in the breathing zone of the worker. Handling CuO nanoparticles increased the concentration of small particles (<?58 nm) inside the fume hood (up to 1?×?10⁵ cm^?3). Synthesis, handling and packaging of ZnO and TiO₂ nanoparticles did not result in detectable particle release to the laboratory air. Simulated powder spills showed a systematic increase in the particle concentrations inside the fume hood with increasing amount of material and drop height. Despite powder spills were sometimes observed to eject into the laboratory room, the spill events were rarely associated with notable release of particles from the fume hood. Overall, this study shows that a fume hood generally offers sufficient exposure control during synthesis and handling of nanomaterials. An appropriate fume hood with adequate sash height and face velocity prevents 98.3% of particles release into the surrounding environment. Care should still be made to consider spills and high cleanliness to prevent exposure via resuspension and inadvertent exposure by secondary routes.     

Particle Size of X-ray Pumped UVC-Emitting Nanoparticles Defines Intracellular Localization and Biological Activity Against Cancer Cells

Effectiveness of radiation treatment for cancer is limited in hypoxic tumors. Previous data shows that UVC-emitting nanoparticles enhance cytotoxicity of X-ray irradiation in hypoxic tumor cells. This study examines the impact on cell killing, particle size, uptake into cells, incubation time, and UV emission intensity of LuPO₄:Pr³⁺,Nd³⁺. A549 cells are treated with LuPO₄:Pr³⁺,Nd³⁺ and X-rays. The surviving fraction is evaluated using the colony formation assay after treatment of cells with different particle sizes (D₅₀ = 0.16 and 5.05 µm) and after different incubation times before X-ray irradiation. Nanoparticle uptake into cells is verified by transmission electron microscopy and quantified by inductively coupled plasma mass spectrometry. The microparticles exhibit a five times higher emission intensity compared to nanoparticles. Both particle sizes show an increased cytotoxic effect after X-ray excitation with prolonged incubation times. Surprisingly, the smaller nanoparticles show a significantly higher biological effect compared to the larger particles, despite their significantly lower UVC emission. Nanoparticles accumulate more quickly and closer to the nucleus than the microparticles, resulting in higher localized UVC emission and greater lethality. The results suggest that the number of intracellular particles and their proximity to the cell DNA is more important than the emission intensity of the particles.     

One-step synthesis of dye-incorporated porous silica particles

Fluorescent nanoparticles have a variety of biomedical applications as diagnostics and traceable drug delivery agents. Highly fluorescent porous silica nanoparticles were synthesized in a water/oil phase by a microemulsion method. What is unique about the resulting porous silica nanoparticles is the combination of a single-step, efficient synthesis and the high stability of its fluorescence emission in the resulting materials. The key of the success of this approach is the choice of a lipid dye that functions as a surrogate surfactant in the preparation. The surfactant dye was incorporated at the interface of the inorganic silica matrix and organic environment (pore template), and thus insures the stability of the dye?Csilica hybrid structure. The resulting fluorescent silica materials have a number of properties that make them attractive for biomedical applications: the availability of various color of the resulting nanoparticle from among a broad spectrum of commercially dyes, the controllablity of pore size (diameters of ~5?nm) and particle size (diameters of ~40?nm) by adjusting template monomer concentration and the water/oil ratio, and the stability and durability of particle fluorescence because of the deep insertion of surfactant??s tail into the silica matrix.     

Synthesis of CaWO<Subscript>4</Subscript> nanocolloidal suspension via pulsed laser ablation and its optical properties

Pulsed laser ablation (PLA) in the liquid phase was successfully employed to synthesize calcium tungstate (CaWO₄) nanocolloidal suspension. The crystalline phase, particle morphology and laser ablation mechanism for the colloidal nanoparticles were investigated using XRD, TEM and SEM. The obtained colloidal suspension consisted of well-dispersed CaWO₄ nanoparticles which showed a spherical shape with sizes ranging from 5 to 30 nm. The laser ablation and the nanoparticle forming process were discussed under consideration of the photo-ablation mechanism, where the nanoparticles were generated by rapid condensation of the plume in high pressured ethanol vapor. The optical properties of the prepared CaWO₄ colloidal nanoparticles were analyzed in detail using XPS, Raman spectroscopy, UV-Vis spectroscopy and PL spectrophotometry. The optical band gap was estimated by Tauc and Menths law. PACS 42.62.-b; 82.70.Dd; 78.55.Hx; 81.07.Wx     

Controlled release of ketorolac through nanocomposite films of hydrogel and LDH nanoparticles

A novel nanocomposite film for sustained release of anionic ophthalmic drugs through a double-control process has been examined in this study. The film, made as a drug-loaded contact lens, consists principally of a polymer hydrogel of 2-hydroxyethyl methacrylate (HEMA), in whose matrix MgAl-layered double hydroxide (MgAl-LDH) nanoparticles intercalated with the anionic drug are well dispersed. Such nanocomposite films (hydrogel-LDH-drug) contained 0.6–0.8 mg of MgAl-LDH and 0.08–0.09 mg of the ophthalmic drug (ketorolac) in 1.0 g of hydrogel. MgAl-drug-LDH nanoparticles were prepared with the hydrodynamic particle size of 40–200 nm. TEM images show that these nanoparticles are evenly dispersed in the hydrogel matrix. In vitro release tests of hydrogel-LDH-drug in pH 7.4 PBS solution at 32 °C indicate a sustained release profile of the loaded drug for 1 week. The drug release undergoes a rapid initial burst and then a monotonically decreasing rate up to 168 h. The initial burst release is determined by the film thickness and the polymerization conditions, but the following release rate is very similar, with the effective diffusion coefficient being nearly constant (3.0 × 10⁻¹² m²/s). The drug release from the films is mechanistically attributed to anionic exchange and the subsequent diffusion in the hydrogel matrix.     

Magnetic nanoparticles for a new drug delivery system to control quercetin releasing for cancer chemotherapy

Quercetin belongs to the chemical class of flavonoids and can be found in many common foods, such as apples, nuts, berries, etc. It has been demonstrated that quercetin has a wide array of biological effects that are considered beneficial to health treatment, mainly as anticancer. However, therapeutic applications of quercetin have been restricted to oral administration due to its sparing solubility in water and instability in physiological medium. A drug delivery methodology was proposed in this work to study a new quercetin release system in the form of magnetite?Cquercetin?Ccopolymer (MQC). These materials were characterized through XRD, TEM, IR, and Thermal analysis. In addition, the magnetization curves and quercetin releasing experiments were performed. It was observed a nanoparticle average diameter of 11.5 and 32.5?nm at Fe₃O₄ and MQC, respectively. The presence of magnetic nanoparticles in this system offers the promise of targeting specific organs within the body. These results indicate the great potential for future applications of the MQC to be used as a new quercetin release system.     

Irradiation effect of low-energy ion on polyurethane nanocoating containing metal oxide nanoparticles

Irradiation effect of low-energy ion beam has been investigated on nanocoating developed with silica, titania and silica–titania core–shell nanoparticles embedded in an organic binder for nanopaint application. In this work, we have taken polyurethane as a model organic binder. Silica nanoparticles have been prepared through sol–gel synthesis with a particle size of 85?nm. Titania and core–shell nanoparticles have been prepared through both sol–gel and peptization process. Particle sizes obtained were 107?nm for titania and 240?nm for core–shell nanoparticles prepared through sol–gel process and 75?nm for TiO₂ and 144?nm for core–shell nanoparticles prepared through peptization process. The coating formulations were developed with the above nanoparticles individually and nanoparticle concentration was varied from 1 to 6?wt% and the best performance in terms of hydrophobicity was obtained with 4?wt % of the nanoparticles in polyurethane coating formulation. All the coating formulations prepared were applied on a glass substrate and dried at 100°C. The dry film thickness obtained was around 100?µm in each case. These films dried on glass substrate were irradiated by nitrogen and argon ion beam with energy of 26?keV at fluences of 10¹⁴ to 10¹⁶?ions/cm². The anti-algal property of the irradiated samples was improved and hydrophobicity was reduced.     

In Vitro Studies of Fe3O4-ZIF-8 Core–Shell Nanoparticles Designed as Potential Theragnostics

Theragnostics represent a combination of therapy and diagnosis within one system. Herein, Fe₃O₄-ZIF-8 core–shell nanoparticles are developed and suggested as candidates for theragnostic applications in cancer treatment. A drug loaded metal–organic framework ZIF-8 (zeolitic imidazolate framework-8) represents the therapeutic tool, while the Fe₃O₄ core is included to enable the material visualization by magnetic resonance imaging (MRI). A reliable synthesis of Fe₃O₄-ZIF-8 core–shell nanoparticles of an average size below 100 nm is reported. The nanoparticles are characterized by FT-IR, TGA, XRPD, TEM, STEM-EDS, DLS, ICP-OES, CHN-elemental analysis, SQUID measurements, and MRI. Moreover, their chemical stability and in vitro cytotoxicity against fibroblast and selected cancer cell lines are evaluated. As a model drug, arsenic trioxide—a promising anticancer drug—is used. The drug release can be triggered by a pH change from 7.4 to 6.0 and the nanoparticles can be visualized by MRI in vitro, thus a potential theragnostic agent for cancer treatment is developed.     

Synthesis and characterization of Rh(PVP) nanoparticles studied by XPS and NEXAFS

Rhodium nanoparticles were synthesized by the reduction of Rh³⁺ ion in ethanol solvent with use of the polyvinylpyrrolidone (PVP) of various molecular weights and the solvent of different volume ratios of water to ethanol. The formed Rh(PVP) nanoparticles have been characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and near edge X-ray absorption fine structure (NEXAFS) techniques. The TEM and AFM results show that the Rh(PVP) nanoparticles are monodispersed and do not agglomerate with each other. The particle size can be controlled by the molecular weight of PVP and/or the water/ethanol ratio of the solvent. The XPS and NEXAFS results indicate that the chlorine derived from RhCl₃(3H₂O) remains in the obtained nanoparticles but can be removed by heating.     

Synthesis and properties of magnetic and luminescent Fe3O4/SiO2/Dye/SiO2 nanoparticles

A simple and reproducible method was developed to synthesize a novel class of Fe₃O₄/SiO₂/dye/SiO₂ composite nanoparticles. As promising candidates for use in bioassays, the obtained nanoparticles have an average diameter of 30 nm, and the thickness of the outer shell of silica could be tuned by changing the concentration of the silicon precursor tetraethyl orthosilicate during the synthesis. These multifunctional nanoparticles were found to be highly luminescent, photostable and superparamagnetic. The luminescence intensity of the nanoparticles was increased as the dye concentration was increased in the preparation process. The color of the luminescence was successfully tuned by incorporating different dyes into the nanoparticles. The measurements of the emission spectra indicated that relative to the dye molecules dissolved in ethanol, the emission of the dye-doped nanoparticles exhibited either a red shift or a blue shift, to which a tentative explanation was given.     

Mesoporous silica-coated NaYF4:Yb3+, Er3+ particles for drug release

NaYF₄:Yb³⁺, Er³⁺ nanoparticles were successfully prepared by a polyol process using diethyleneglycol (DEG) as solvent. These NaYF₄:Yb³⁺, Er³⁺ nanoparticles can be coated with mesoporous silica using nonionic triblock copolymer EO₂₀PO₇₀EO₂₀ (P 123) as structure-directing agent and other materials. The composites can load ibuprofen and release the drug in the phosphate buffer solution (PBS). The composites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen absorption/desorption isotherms, fluorescence spectra, and UV/Vis absorption spectra, respectively. The composites have the mesoporous structure. In addition, the composites emit red fluorescence (from Er³⁺) under 980 nm near infrared laser excitation, which can be used as fluorescent probes in the drug-delivery system.     

Effects of temperature gradient induced nanoparticle motion on conduction and convection of fluid

The continuous synthesis of nickel nanoparticles (NiNPs) in a static microchannel T-mixer by the reduction of NiCl₂·6H₂O in the presence of ethylene glycol without a stabilizing/capping agent was investigated. The nanoparticles were formed in accordance with the modified polyol process with hydrazine used as a reducing agent and NaOH as a catalyst for nanoparticle formation. The reaction mechanism for NiNP formation was investigated in batch with the help of Fourier transform infrared spectroscopy and X-ray diffraction (XRD) techniques. Parameters were found for reducing reaction times from 60 to 1?min. The effects of temperature (60?C120?°C) and NaOH concentration (0.1 and 0.5?M) on batch-processed particle characteristics were also studied using XRD, transmission electron microscope and electron microprobe analysis. Average particle size was reduced from 9.2?±?2.9 to 5.4?±?0.9?nm at higher temperature and NaOH concentration. Adaptation of this chemistry to a static microchannel T-mixer for continuous synthesis resulted in smooth, spherical particles. Increases in the reaction temperature from 120 to 130?°C resulted in a narrow size distribution of 5.3?±?1?nm and also resulted in magnetic properties of 5.1?emu/g (saturation magnetization), 1.1?emu/g (remanent magnetization), and 62?Oe (coercivity).     

A Multifunctional Nanocrystalline CaF2:Tm,Yb@mSiO2 System for Dual‐Triggered and Optically Monitored Doxorubicin Delivery

Daunting challenges in investigating the controlled release of drugs in complicated intracellular microenvironments demand the development of stimuli‐responsive drug delivery systems. Here, a nanoparticle system, CaF₂:Tm,Yb@mSiO₂, made of a mesoporous silica (mSiO₂) nanosphere with CaF₂:Tm,Yb upconversion nanoparticles (UCNPs) is developed, filling its mesopores and with its surface‐modified with polyacrylic acid for binding the anticancer drug molecules (doxorubicin, DOX). The unique design of CaF₂:Tm,Yb@mSiO₂ enables us to trigger the drug release by two mechanisms. One is the pH‐triggered mechanism, where drug molecules are preferentially released from the nanoparticles at acidic conditions unique for the intracellular environment of cancer cells compared to normal cells. Another is the 808 nm near infrared (NIR)‐triggered mechanism, where 808 nm NIR induces the heating of the nanoparticles to weaken the electrostatic interaction between drug molecules and nanoparticles. In addition, luminescence resonance energy transfer occurs from the UCNPs (the energy donor) to the DOX drug (the energy acceptor) in the presence of 980 nm NIR irradiation, allowing us to monitor the drug release by detecting the vanishing blue emission from the UCNPs. This study demonstrates a new multifunctional nanosystem for dual‐triggered and optically monitored drug delivery, which will facilitate the rational design of personalized cancer therapy.