Stability Of Dyes Research Articles

Dye stability of black cherry plum anthocyanins in the interaction with co-pigments and sucrose sweetener.

In this research, the co-pigmentation reactions between black cherry plum (Prunus cerasifera Ehrh. cv. Pissardii Nigra) anthocyanins and caffeic, gallic, 4-hydroxybenzoic, malic, and tannic acids with different concentrations (0, 120, 240, 480, and 960 mg L-1) at various temperatures (20, 40, 60, 80, and 100°C) were investigated at pH 3.5. The strongest immediate co-pigmentations resulted at 960 mg L-1, being significantly highest using tannic acid at all temperatures. In addition, the anthocyanin stability and the brown polymeric color formation were investigated in the presence of different concentrations of sucrose sweetener (0, 30, and 60%) and different pHs (2 and 3) in the range of 0-60 h. Also, the amount of furfural was measured in the presence of 0% and 30% sucrose concentrations at pH 2 after 20 h at 90°C by HPLC (high-performance liquid chromatography), and the most polymeric color formation was observed in the concentration of 60% sucrose at pH 2 after 60 h.

A novel polymer platform for endoscopic tattooing with high efficacy and safety.

Endoscopic tattooing plays a pivotal role in modern endoscopic localization of gastrointestinal lesions, facilitating further surgical intervention and aiding in the postoperative identification and repositioning of lesions. However, traditional endoscopic tattoo dyes often suffer from drawbacks such as side effects, short tattoo duration, and high overall costs. In this study, we developed polyvinylpyrrolidone (PVP)-modified polypyrrole (PPy) nanoparticles by oxidizing pyrrole in a PVP aqueous solution to create a PPy/PVP nanoparticle solution. This innovation aims to enhance endoscopic tattooing efficiency and mitigate the limitations associated with current tattooing methods. Both in vitro and in vivo evaluations confirmed the biosafety of PPy/PVP nanoparticles. Endoscopic tattooing experiments conducted in a pig model demonstrated the dye's stability within the digestive tract. Similarly, subcutaneous tissue tattooing experiments performed in a mouse model revealed the sustained stability of the PPy/PVP tattoo dye for at least 180days. With its robust stability, safety, and longevity, PPy/PVP nanoparticles hold promise as novel tattoo dyes for marking intestinal lesion sites. This advancement has the potential to enhance the accuracy of lesion localization and long-term tracking.

Aromatic vs. aliphatic linkers: impact on dye loading and stability in oligoglycerol-derived dendronized polymersomes

We report the synthesis and self-assembly of oligoglycerol-based dendronized polythiourethanes, which consist of an aliphatic or aromatic linker. Using FRET, the effect of the linker was understood and the dye exchange mechanism was unravelled.

Efficient removal of carcinogenic Rosaniline Hydrochloride (Fuchsine) dye with Mg doped FeTiO nanocomposites: Experimental and statistical evaluation

This study focuses on the synthesis of new nanostructured absorbent materials and removal of hazardous Rosaniline Hydrochloride (fuchsine) dye from polluted water. For this, Mg doped FeTiO nanocomposite (FTMO-NCs) was synthesized by co-precipitation method and thoroughly characterized to study its surface properties. The TEM image shows the FTMO-NCs are consists of crystalline particles sized in few nanometers of scale. The SAED pattern suggests the nanoscale polycrystalline nature of the FTMO-NCs. The homogeneously distributed MgO on the FeTiO-NCs further validates the spectra. Furthermore, the successful mixture of MgO with the FeTiO surface and the formation of FTMO-NCs are indicated by the well-defined elemental mapping of Fe, Ti, O, and Mg. Dye adsorption capacity, stability, and regeneration capability of the synthesized FTMO-NCs was evaluated by a series of experiments and varying parameters, such as, agitation time, nanocomposite mass, solution pH, dye concentration, etc. The pseudo-second-order kinetic model was found to be applicable based on the kinetic parameters calculated with a high correlation coefficient of 0.999. The findings indicate that the Langmuir isotherm is a better fit for the experimental data for the fuchsine adsorption on the FTMO-NPs in comparison to the other four models and shows the maximum adsorption capacity (Qmax) of 555.5 mg/g. Moreover, a double layer model was applied to study the statistical prediction of the favorability of the adsorption process of the dye on the nanocomposite. The Nm value for fuchsine adsorption was 550 mg/g, 255 mg/g, and 218 mg/g, respectively at 298 K, 308 K, and 318 K. The use of Mg-doped FeTiO nanocomposites (FTMO-NCs) for removing Rosaniline Hydrochloride (fuchsine) dye is a novel approach that brings together the unique properties of both materials. The incorporation of magnesium (Mg) into the FeTiO nanocomposite introduces new synergies and enhances the adsorption capabilities of the material. This innovation is particularly significant because Mg doping can influence the surface chemistry and electronic structure of the nanocomposite, leading to improved dye removal efficiency.

D- π-A azo dyes bearing thiazole-diphenylamine units: Synthesis, photophysical and molecular structure properties, and use for dyeing of polyester fabrics

Herein, six new thiazole-dipehenylamine-based azo dyes containing azo and thiazole bridges and diphenylamine donor with different donor/acceptor groups were synthesized. All the synthesized dyes were characterized by FT-IR, NMR and HRMS analyses. The structure of (E)-N-methyl-4-((thiazol-2-yl)diazenyl)-N-phenylaniline (4) was conclusively confirmed by single crystal X-ray diffraction analysis. Photophysical studies were performed in different solvents with various polarity. Although the three synthesized compounds can be represented as potential azo-hydrazone tautomers only the azo form was observed in all solvents used. UV/vis spectroscopic studies showed that the color changed dramatically when the dyes contain a strong electron accepting nitro substituent. Moreover, after protonation of azo dyes, with the exception of the azo dyes with nitro group, a bathochromic shift was observed. The effects of protonation on the geometry and electronic structure of the compounds were studied, and the NLO properties were also investigated using DFT calculations. In addition, the thermal stability of the azo dyes was investigated using thermal gravimetry (TGA). Dyeing performance was evaluated with these dyes on polyester fabric in an aqueous medium. All dyes except dyes 3 and 6 showed good color fastness properties. Therefore, these compounds can be used as textile dyes for polyester fabrics.

Ti3C2-MXene/NiO Nanocomposites-Decorated CsPbI3 Perovskite Active Materials under UV-Light Irradiation for the Enhancement of Crystal-Violet Dye Photodegradation

Ti3C2-MXene material, known for its strong electronic conductivity and optical properties, has emerged as a promising alternative to noble metals as a cocatalyst for the development of efficient photocatalysts used in environmental cleanup. In this study, we investigated the photodegradation of crystal-violet (CV) dye when exposed to UV light using a newly developed photocatalyst known as Ti3C2-MXene/NiO nanocomposite-decorated CsPbI3 perovskite, which was synthesized through a hydrothermal method. Our research investigation into the structural, morphological, and optical characteristics of the Ti3C2-MXene/NiO/CsPbI3 composite using techniques such as FTIR, XRD, TEM, SEM–EDS mapping, XPS, UV–Vis, and PL spectroscopy. The photocatalytic efficacy of the Ti3C2-MXene/NiO/CsPbI3 composite was assessed by evaluating its ability to degrade CV dye in an aqueous solution under UV-light irradiation. Remarkably, the Ti3C2-MXene/NiO/CsPbI3 composite displayed a significant improvement in both the degradation rate and stability of CV dye when compared to the Ti3C2-MXene/NiO nanocomposite and CsPbI3 perovskite materials. Furthermore, the UV–visible absorption spectrum of the Ti3C2-MXene/NiO/CsPbI3 composite demonstrated a reduced band gap of 2.41 eV, which is lower than that of Ti3C2-MXene/NiO (3.10 eV) and Ti3C2-MXene (1.60 eV). In practical terms, the Ti3C2-MXene/NiO/CsPbI3 composite achieved an impressive 92.8% degradation of CV dye within 90 min of UV light exposure. We also confirmed the significant role of photogenerated holes and radicals in the CV dye removal process through radical scavenger trapping experiments. Based on our findings, we proposed a plausible photocatalytic mechanism for the Ti3C2-MXene/NiO/CsPbI3 composite. This research may open up new avenues for the development of cost-effective and high-performance MXene-based perovskite photocatalysts, utilizing abundant and sustainable materials for environmental remediation.

Optimized Two‐Color Single‐Molecule Tracking of Fast‐Diffusing Membrane Receptors

AbstractSingle particle tracking (SPT) combined with total internal reflection fluorescence microscopy (TIRFm) is an outstanding approach to decipher mechanisms on the cell membrane at the nanoscale. Multicolor configurations, needed to investigate interactions, are still hindered by several challenges. This work systematically and quantitatively analyzes the impact of necessary elements of SPT‐TIRFm setups on the signal‐to‐noise ratio (SNR), which must be optimized especially in dynamic studies needing minimally invasive dyes for biomolecule labeling. Autofluorescence originating from commonly used optical glass results in the dominant limiting factor in TIRFm, and a cover glass material is tested yielding significant SNR improvements in multichannel TIRFm. Moreover, methodologies are optimized for reducing fluorophore photobleaching in multicolor implementations requiring simultaneous stabilization of multiple dyes. The developed strategies are applied to the fast p75NTR receptors labeled by two fluorophores on the membrane of living cells, achieving reliable, simultaneous two‐color SPT, contrary to configurations using standard cover glasses. This work highlights the importance of optical materials suitable for microscopy and with reduced autofluorescence for increasing sensitivity toward ultimate spatiotemporal resolutions. In particular, the present protocols can pave the way for multicolor super‐resolved localization and tracking of single molecules by TIRFm, greatly expanding the potential of SPT.

Revolutionizing Wastewater Treatment: Harnessing Metal–Organic Frameworks for Exceptional Photocatalytic Degradation of Azo-Type Dyes

Due to the high stability of azo-type dyes, conventional treatment processes such as adsorption, flocculation, and activated sludge are not efficient for decolorizing wastewater effluents. An alternative to traditional wastewater treatment is photocatalysis, which has gained significant interest because research has shown it to be a viable and cost-effective process that uses sunlight as an inexhaustible energy source. In heterogeneous photocatalysis, a photocatalyst is required, such as TiO2, ZnO, composite materials, and, more recently, metal–organic frameworks (MOFs). MOFs, also known as “coordination polymers”, exhibit photocatalytic properties and have been proven to be promising materials in the photocatalytic degradation of dyes. This study presents recent advances in using MOFs as photocatalysts to degrade recalcitrant contaminants like azo-type dyes. Recent advancements in developing photocatalysts based on MOFs are focused on two strategies. Firstly, the development of new MOFs composed of complex ligands or a mixed ligand system, and secondly, the synthesis of composite materials based on MOFs and metal oxides, metals, sulfides, nitrides, etc. Both strategies have significantly contributed to the search for new semiconductors to degrade some recalcitrate contaminants in wastewater.

Substituents-triggered modulation of structure and alkali resistance in cyano-based disperse dyes

Alkali-resistant disperse dyes have garnered significant interest due to their numerous advantages in alkaline one-bath dyeing procedures. Herein, six cyano-based disperse dyes (D1–D6) with either 2-aminobenzothiazole or 2-amino-6-nitrobenzothiazole, as well as N-substituted anilines as coupling components, were designed and synthesized to investigate the effect of substituents and π-π conjugation of the alkali-resistant stability of dyes. High-performance liquid chromatography (HPLC) was used to monitor the dye hydrolysis behavior, indicating that dyes with strong intramolecular π-π conjugation and bulky benzyl substituents on the n-phenylamine substituent exhibited good alkaline resistance. The hydrolysis processes of cyano disperse dyes under alkaline conditions were consistent with SN2 Nucleophilic substitution, and followed first-order reaction kinetics. Furthermore, PET fabrics were dyed with D1–D3 under various alkaline conditions, proving that D2 and D3 possessed good dyeing performance even under a 5 g/L NaOH dye bath. Our study contributes valuable insights into the relationship between molecular structure and alkali resistance in cyanide disperse dyes, offering practical guidance for enhancing the performance of such dyes.

Optical traps induce fluorophore photobleaching by two-photon excitation

Techniques combining optical tweezers with fluorescence microscopy have become increasingly popular. Unfortunately, the high-power, infrared lasers used to create optical traps can have a deleterious effect on dye stability. Previous studies have shown that dye photobleaching is enhanced by absorption of visible fluorescence excitation plus infrared trap photons, a process that can be significantly reduced by minimizing simultaneous exposure to both light sources. Here, we report another photobleaching pathway that results from direct excitation by the trapping laser alone. Our results show that this trap-induced fluorescence loss is a two-photon absorption process, as demonstrated by a quadratic dependence on the intensity of the trapping laser. We further show that, under conditions typical of many trap-based experiments, fluorescence emission of certain fluorophores near the trap focus can drop by 90% within 1 min. We investigate how photostability is affected by the choice of dye molecule, excitation and emission wavelength, and labeled molecule. Finally, we discuss the different photobleaching pathways in combined trap-fluorescence measurements, which guide the selection of optimal dyes and conditions for more robust experimental protocols.

Textile dye decolourisation of yeast isolated from Tuak starter culture

The textile industry is one of the largest industries in the world and contributes positively to the economic growth of a country. However, the improper disposal of textile dye effluents results in discharging of high concentrations of textile dyes into the environment. Moreover, the inherent stability of textile dyes makes them hard to remove from the environment, which can harm organisms in polluted areas. Biological decolourisation was considered as a strategy to remediate textile dyes. Microbial decolourisation of textile dyes involves using various species of bacteria and fungi from different sources that can degrade or accumulate dye molecules. Although Indonesia is a well–known country with rich biodiversity, research on microbial decolourisation is still limited. Therefore, this study explored the decolourisation potential of microbes from the starter culture of Tuak, a traditional Indonesian alcoholic beverage made from fermented sugar palm or rice. Potential microbes were screened on yeast peptone dextrose solid agar (YPD) supplemented with various textile dyes. Isolates that formed a clear zone around the colony were further examined for decolourisation activity in broth culture media, and the decrease in dye concentration was measured spectrophotometrically. The results showed that two potential yeast isolates could decolourise Congo red and malachite green. Identification of the isolates by observation of colony and cell morphology and biochemical characteristics indicated that the two isolated yeasts belonged to the genera Saccharomyces and(or) Candida.

Fabrication of Microcapsule-Type Long-Lasting Phosphorescent Sensor for Concrete Crack Monitoring

The generation and expansion of cracks in concrete structures reduce the durability and safety of structures. In order to detect cracks in concrete structures, a long-lasting phosphorescent microcapsule coating is proposed in this study. The microcapsule-based sensor is pasted on the surface of cement-based materials and solidified. The microcapsules become ruptured and cause the core material to flow out when the microcracks occur on the material, which emits strong phosphorescence at the cracked position under UV irradiation. The results indicate that the successful encapsulation of microcapsules could enhance the thermal stability of phosphorescent dye. The excitation wavelength of the phosphorescent microcapsules is also investigated. The phosphorescent microcapsules could effectively highlight unnoticeable cracks by a long-lasting phosphorescence response in the cracking region. The mechanical properties of microcapsules/epoxy resin composite coatings were studied, and the optimal content of microcapsules in the coating was determined. The as-fabricated phosphorescent microcapsules have good damage-sensing effects in conditions of different light and temperatures. The method proposed in this study will assist in the further development of damage-sensing material in the field of concrete crack monitoring.

Effect of heat and UV-irradiation on chitosan film doped with BODIPY dyes

The chitosan (CS) films modified by two photosensitive BODIPY compounds, differing in the presence of iodine atoms in the 2,6 position in the compound core, have been prepared and studied for thermal stability in an inert atmosphere as well as for photochemical resistance in air using highly energetic UV radiation. Characterization of UV exposed samples has been done by UV–Vis and FTIR spectroscopy and contact angle measurement, while the heat effect has been tested by thermogravimetric analysis. The photochemical stability of BODIPY dyes in solid CS matrix has been found to be relatively good. CS containing compound with iodine atoms in structure exhibits a little worse photostability than their counterparts without this element. The contact angle measurements indicate that the effect of UV radiation on surface properties is somewhat different than occurred in the sample bulk: BODIPYs efficiently hamper the surface photooxidation of CS. No effect of BODIPY on chitosan thermal stability was noted, while dyes decompose earlier, i.e., at lower temperatures in the presence of CS than heated alone. The mechanism of reactions caused by heat and UV radiation has been discussed. The protective effect of CS on BODIPY was found, which allows the prediction of a wide application of such systems in many industrial sectors, e.g., for the production of fluorescent labels and photo sensors.

New copper (II) complexes derived from azo pyridone dyes: Structure characterization, thermal properties, and molecular docking studies

Two azo dye ligands, bearing different substituents (chlorine atom or methoxy group) in the para‐position of the phenyl ring, were employed for the synthesis of two Cu(II) chelates. Full structural affirmation of complexes was assessed. X‐ray diffraction measurements revealed that the coordination geometry for Cu atoms in both complexes is square‐pyramidal with a ligand:metal ratio of 2:1 where dyes behave as monobasic bidentate ligands. Thermogravimetric analyses of the complexes and their starting dyes were performed to study their thermal stabilities and decomposition behavior confirming the thermal stability of both dyes and complexes. Antioxidative activity of the complexes has been assigned and compared with their parent ligands revealing that the presence of the electron–donor, methoxy group, in the phenyl ring, in both dye and complex, is responsible for the activity (IC50 values of 1.54 for the dye and 1.30 mM for the complex). It should be stated that the complexation of the methoxy‐substituted dye leads to enhanced antioxidative activity concurrent to a standard antioxidant molecule of ascorbic acid, making this molecule a promising antioxidant agent. Docking study with vascular endothelial growth factor receptor 2 and Aurora kinase A proteins indicate that complexes exhibit higher binding affinities to proteins than the starting ligand dyes. The most promising structure exhibiting the best docking potential toward both proteins is the complex‐bearing methoxy group. The presented results represent a promising start for further investigations of these compounds as potential therapeutic candidates for the treatment of various types of cancer.

Harnessing Natural Colorant From Brown Algae TURBINARIA CONOIDES ( J. AGARDH) KUETZ For Fabric Dyeing: A Sustainable Eco- Friendly Approach

The demand for natural dyes in the modern world is increasing day by day. These resources have become important for their use in food, pharmaceuticals and textiles Industries, instead of their synthetic dyes. Using these resources we can protect human health and prolong life on the earth. This research focuses on Turbinaria conoides, a brown seaweed collected from Olakuda, Ramanathapuram coast, Tamil Nadu, India (9.2876° N, 79.3129° E). A crude dye was extracted from the seaweed and used to treat cotton fabric using the pre-mordanting technique. To achieve different shades of colors, Turbinaria conoides was combined with other dye-yielding plant materials, including Vachellia nilotica, Oldenlandia umbellate, Rubia cordifolia, and Alkanna tinctoria. The phytochemical analysis confirmed the presence of bioactive compounds in Turbinaria conoides. Colorfastness tests were conducted to evaluate the dye's stability on the fabric. The study concludes that natural dyes hold great potential and interest, especially Turbinaria conoides. India's vast plant resource base presents opportunities for further research and documentation of natural dye usage. Sustainable and eco-friendly practices in the textile industry can be fostered through algal-sourced pigments, contributing to environmental protection and an eco-aware society. Future aspects include a focus on environment-friendly dyes, affordable production methods, and exploring the full potential of natural dyestuffs for various applications, including waste utilization and job creation.

Confinement of Organic Dyes in UiO-66-Type Metal-Organic Frameworks for the Enhanced Synthesis of [1,2,5]Thiadiazole[3,4-g]benzoimidazoles.

Organic dyes as non-noble metal photosensitizers have attracted increasing attention due to their environmental friendliness and sustainability but suffer from fast deactivation and low stability. Here, we reported a fruitful strategy by the confinement and stabilization of visible light-active signal unit organic dyes within the metal-organic frameworks (MOFs) and developed a series of heterogeneous photocatalysts dye@UiO-66s [dye = fluorescein (FL)/rhodamine B (RhB)/eosin Y (EY), UiO-66s = UiO-66, and Bim-UiO-66]. It has been demonstrated that the encapsulated dyes can effectively sensitize MOF hosts and dominate the band structures and photocatalytic activities of dye@UiO-66s regardless of the ligand functionalization of MOFs. Photocatalytic experiments showed that these dye@UiO-66s exhibit enhanced activities relative to free dyes and among them, FL@Bim-UiO-66 displays excellent efficiencies toward the green synthesis of new carbon-bridged annulations, [1,2,5]thiadiazole[3,4-g]benzoimidazoles in the yield of up to 98% at room temperature with outstanding stability and reusability. Furthermore, the intramolecular cyclization intermediate was captured and characterized by the single-crystal X-ray diffraction analysis.

Microencapsulation effect of natural dye extracts of spirulina platensis, dragon fruit peel, and pumpkin skin on antioxidant activity, color stability and particle size

The nature of natural dyes added to food raw materials is easily damaged during processing and exposure to light. This study aimed to determine the effect of microencapsulation on antioxidant activity, color stability, and particle size of the natural dyes produced. This study used three types of commodities to be extracted with the addition of a coating, i.e. spirulina platensis using maltodextrin and carrageenan; dragon fruit peel using maltodextrin and gum arabic; and pumpkin skin using maltodextrin and gelatine. The tests observed were antioxidant activity, changes in color stability with light and without light parameters, and particle size. The results showed that the antioxidant activity of natural dyes after microencapsulation increased the IC50 value. IC50 value of spirulina platensis extracts increased from 2164.75 ppm to 4026.96 ppm; dragon fruit peel extracts increased from 688.91 ppm to 2403.71 ppm, and pumpkin skin extracts increased from 1025.62 ppm to 4327.92 ppm. Color stability of spirulina extract stored for 10 days showed unstable color. Color stability of fruit peel extract storaged for 10 days showed less stable, whereas color stability of pumpkin skin extract is stable. While the color stability without the light on the Spirulina platensis extract during stored for 10 days is stable, whereas color stability of the dragon fruit peel extract and pumpkin skin extract were unstable. The particle size of each microencapsulates meet the microencapsulated particle size requirements.

Doubly Strapped Zwitterionic NIR‐I and NIR‐II Heptamethine Cyanine Dyes for Bioconjugation and Fluorescence Imaging

AbstractHeptamethine cyanine dyes enable deep tissue fluorescence imaging in the near infrared (NIR) window. Small molecule conjugates of the benchmark dye ZW800‐1 have been tested in humans. However, long‐term imaging protocols using ZW800‐1 conjugates are limited by their instability, primarily because the chemically labile C4′‐O‐aryl linker is susceptible to cleavage by biological nucleophiles. Here, we report a modular synthetic method that produces novel doubly strapped zwitterionic heptamethine cyanine dyes, including a structural analogue of ZW800‐1, with greatly enhanced dye stability. NIR‐I and NIR‐II versions of these doubly strapped dyes can be conjugated to proteins, including monoclonal antibodies, without causing undesired fluorophore degradation or dye stacking on the protein surface. The fluorescent antibody conjugates show excellent tumor‐targeting specificity in a xenograft mouse tumor model. The enhanced stability provided by doubly strapped molecular design will enable new classes of in vivo NIR fluorescence imaging experiments with possible translation to humans.

Doubly Strapped Zwitterionic NIR-I and NIR-II Heptamethine Cyanine Dyes for Bioconjugation and Fluorescence Imaging.

Heptamethine cyanine dyes enable deep tissue fluorescence imaging in the near infrared (NIR) window. Small molecule conjugates of the benchmark dye ZW800-1 have been tested in humans. However, long-term imaging protocols using ZW800-1 conjugates are limited by their instability, primarily because the chemically labile C4'-O-aryl linker is susceptible to cleavage by biological nucleophiles. Here, we report a modular synthetic method that produces novel doubly strapped zwitterionic heptamethine cyanine dyes, including a structural analogue of ZW800-1, with greatly enhanced dye stability. NIR-I and NIR-II versions of these doubly strapped dyes can be conjugated to proteins, including monoclonal antibodies, without causing undesired fluorophore degradation or dye stacking on the protein surface. The fluorescent antibody conjugates show excellent tumor-targeting specificity in a xenograft mouse tumor model. The enhanced stability provided by doubly strapped molecular design will enable new classes of in vivo NIR fluorescence imaging experiments with possible translation to humans.

Green synthesize of nano-MOF-ethylcellulose composite fibers for efficient adsorption of Congo red from water

Two novel MOF- ethyl cellulose (EC)- based nanocomposites have been designed and synthesized in water by electrospinning and applied for adsorption of congo red (CR) in water. Nano- Zeolitic Imidazolate Framework-67 (ZIF-67), and Materials of Institute Lavoisier (MIL-88A) were synthesized in aqueous solutions by a green method. To enhance the dye adsorption capacity and stability of MOFs, they have been incorporated into EC nanofiber to prepare composite adsorbents. The performance of both composites in the absorption of CR, a common pollutant in some industrial wastewaters, has then been investigated. Various parameters including initial dye concentration, the dosage of the adsorbent, pH, temperature and contact time were optimized. The results indicated 99.8 and 90.9% adsorption of CR by EC/ZIF-67 and EC/MIL-88A, respectively at pH = 7 and temperature at 25 °C after 50 min. Furthermore, the synthesized composites were separated conveniently and successfully reused five times without significant loss of their adsorption activity. For both composites, the adsorption behavior can be explained by pseudo-second-order kinetics, Intraparticular diffiusion and Elovich models demonstrated that the experimental data well matched to the pseudo-second-order kinetics. Intraparticular diffiusion model showed that the adsorption of CR on EC/ZIF-67 and EC/MIL-88a took place in one and two steps, respectively. Freundlich isotherm models and thermodynamic analysis indicated exothermic and spontaneous adsorption.