Indigo Carmine Research Articles

Zn-Al layered double hydroxide nanoparticles for efficient removal of food dyes from wastewater

The ability of layered double hydroxides clay (LDH) produced from ZnAl-NO3 to remove Sunset Yellow FCF (E110), Azorubine (E122), Tartrazine (E102), and Brilliant Blue FCF (E133) from an aqueous solution was studied. The effects of various variables on adsorption were studied. The obtained results show that the adsorption of various food dyes depends on the initial concentration, dose, pH, contact time, and temperature. The adsorption capacities at an equilibrium time of 40 min for E133, E122, E110, and E102 were 18.21, 21.46, 13.19, and 20.58 mg/g, respectively. The adsorption equilibrium data for aqueous solutions were analyzed using Langmuir and Freundlich isotherms and a thermodynamic study. Adsorption kinetics data for aqueous solutions was studied using pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. The morphology for Zn-Al LDH was investigated by scanning electron microscopy (SEM) and BET (pore size = 0.004 cc/g). Equilibrium data were studied by Freundlich, Langmuir, and Temkin isotherms. As for thermodynamics, the value of ∆H° is negative, which means that the adsorption method is exothermic at a temperature range of 288–338 K. ∆S ° is a negative value indicating that the randomness is low, ∆G° is also negative means that the reaction is spontaneous. The FTIR spectroscopic analysis of LDH before and after the adsorption also confirms that the adsorption of food dyes was smooth and spontaneous on Zn-Al LDH providing an excellent and easy-to-use adsorption method for industrial application of wastewater treatment.

U-PEO:CuZnAl as a Recyclable Bifunctional Composite for Absorption/Degradation of Azo-Dyes

The catalytic activity of layered double hydroxide (LDH) and the aqueous solution absorption capacity of ureasil polyethylene oxide (U-PEO) were combined to produce an easily recyclable solidliquid (S-L) reactor (U-PEO:LDH). Scanning electron microscopy (SEM), X-ray diffraction (XRD) and small-angle X-ray scattering (SAXS) of LDH (CuZnAl), U-PEO, and U-PEO:LDH confirmed the layered structure of the catalyst and evidenced its inclusion in the free volume of U-PEO matrix. The catalytic activity of the CuZnAl in the composite prepared with different amounts of LDH, towards degradation of the Acid Blue 29 (AB29) dye by a heterogeneous Fenton-like process was investigated, and the results evidenced a maximum efficiency (96%) for composite with 10 wt.% of LDH. Recyclability assessments demonstrated that the superior performance of the U-PEO:LDH reactor was sustained over several cycles (4). The U-PEO:LDH reactor proposed in this work has excellent potential as a heterogeneous catalyst for effective dye removal in environmental applications.

Photocatalytic degradation of indigo carmine dye by hydrothermally synthesized graphene nanodots (GNDs): investigation of kinetics and thermodynamics.

Graphene nano dots (GNDs) are an intriguing emerging class of materials at the nano scale with distinctive characteristics and exciting potential applications. Graphene oxide was synthesized in a lab setting using a modified version of Hummers' approach and used as a precursor for synthesis of graphene nano dots. Graphene oxide is then treated through hydrothermal treatment to produce GNDs with exact control over their size and form. Synthesized graphene nano dots were subjected to various instruments to study morphology, crystallinity, size and other properties. UV-visible spectroscopy was used to detect the maximum absorbance of light. For functional group identification, FTIR analysis was conducted. X-ray diffraction analysis explained structural composition and various other parameters i.e., crystal size and diameter, which was further verified by Vesta software. Surface morphology of GNDs was analyzed by scanning electron microscopy. AFM analysis of GNDs demonstrates the topography of the surface. The photo degradation of the indigo carmine dye by the GNDs also demonstrates their superiority as UV-visible light driven photo catalysts. To evaluate the results, the thermodynamics and kinetics of the degradation reactions are examined. The effects of several factors, such as temperature, initial concentration, time, pH and catalyst concentration, are also investigated. The data will be analyzed statistically by regression and correlation analysis using dependent and independent variables, regression coefficient and other statistical techniques.

Bio-adsorption of Cationic-Cnionic Dyes from Synthetic Effluents using an Experimental Design Approach

In the current research, Cycas leaves powder (CL) as a low-cost agro-waste adsorbent was investigated for malachite green (MG) and Indigo Carmine (IC) dye removal from contaminated water. The Cycas leaves powder was characterized by Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared (FTIR) techniques. The adsorption parameters were investigated including contact time, dye concentrations, and adsorbent dosage to determine their effects on the adsorption efficiency. The I-optimal design approach was used to intimately detect the significance of adsorption parameters and their interactions by analyzing the overall statistical results. The adsorption isotherm and kinetics were analyzed using two models. The results showed that the data was well-fitted with the Freundlich isotherm model and the adsorption kinetics followed the pseudo-first-order model. The thermodynamics parameters including ΔHº, ΔSº, and ΔGº were determined, and the adsorption process was non-spontaneous, and exothermic for MG and endothermic IC dyes. The results demonstrated that Cycas leave can be exploited as an affordable inexpensive material for the treatment of industrial dyes from textile discharges.

Anomalous spectral shift of localized surface plasmon resonance.

We report the first observation of spectral blue shift of plasmon resonance of synthesized silver nanoparticles (AgNPs) due to a negative optical nonlinearity of a local ambient medium, i.e., indigo carmine (IC) solution at around 420 nm wavelength. The blue shift occurred at a larger concentration of AgNPs or at a larger concentration of IC solution, being in obvious contrast to spectral red shift which was widely witnessed in plasmon spectral shift in a linear regime. Plasmon-enhanced local fields could excite the third-order optical nonlinearity for blue shift even under continuous (non-pulsed) light illumination. We also found that the plasmon-excited nonlinearity could allow for differential nonlinear response of the IC solution to be even greater than its differential linear response, though appearing to be somewhat inconsistent with what was generally known in light-matter interaction. The demonstrated properties of such anomalous shift of plasmon spectral peaks and its accompanying properties indicated that plasmon technologies could be exploited not only in linear but also in nonlinear aspects for critical optimization in plasmon-energy harvesting systems such as in surface enhanced spectroscopy/microscopy, biomedical imaging/sensing, laser frequency conversion, ultrashort pulse generation, and all-optical switching.

Effect of Fe3O4:RGO Ratios in Magnetic Nanocomposites Applied for Dye Discoloration

Nanocomposites of magnetite anchored on reduced graphene oxide with different magnetite:reduced graphene oxide mass ratios were synthesized and evaluated in indigo carmine photo Fenton discoloration. All nanocomposites are magnetic and showed comparable amounts of magnetite and hematite with a higher level of hematite for low iron contents. The highest value of 63.6 emu g-1 was obtained for the nanocomposite with the highest magnetite content. The nanocomposites presented high dispersion of iron oxide particles, at about 12 nm on reduced graphene oxide surface sheets. The samples also showed bandgap energies below that found for bulk magnetite, showing an important effect of reduced graphene oxide. The nanocomposite with an iron nitrate precursors mass ratio of 17:1 showed the best performance (99.7% of indigo carmine discoloration (2.1 × 10-5 mol L-1) at 30 min of reaction, hydrogen peroxide(2.3 × 10-1 mol L-1), and a catalyst dosage of 0.67 g L-1). Reusability tests were performed, and this nanocomposite was shown to be active for at least three recycles. X-ray photoelectron spectrum of Fe2p3/2 showed that the FeIII/FeII ratio was maintained even after three recycles (4 runs), meaning that reduced graphene oxide is responsible for stabilizing magnetite particles, thus maintaining its photocatalytic activity.

Two cobaltous PCPs: rapid catalytic degradation of POPs coupled with remarkable antibacterial and antifungal properties.

In this work, we report the synthesis of two cobalt-based porous coordination polymers (PCPs): [Co3(BTC)2(H2O)12]n (1) and [Co3(BTC)2(DMP)8]n (2) [where BTC = 1,3,5-benzenetricarboxylate and DMP = 3,5-dimethylpyrazole]. These compounds were characterized using a range of physicochemical techniques, including UV-DRS, FT-IR, SCXRD, PXRD, TGA, and FE-SEM/EDX. The synthesized PCPs effectively catalyzed the degradation of various persistent organic pollutants (POPs) rapidly, which includes both cationic and anionic dyes such as Malachite Green (MG), Methylene Blue (MB), Indigo Carmine (IC), Methyl Orange (MO), Orange G (OG), and Eriochrome Black T (EBT). They also have excellent efficacy in degrading nitroaromatics viz. 4-nitrophenol (4-NP), 2,4-dinitrophenol (2,4-DNP), and 2,4,6-trinitrophenol (2,4,6-TNP) in the presence of NaBH4 as a reductant. In addition, these PCPs exhibited remarkable antibacterial and antifungal properties, demonstrating strong activity against bacterial strains such as Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, as well as the fungal strain Candida albicans. These results indicate that these two PCPs have considerable potential for catalyzing the rapid degradation of POPs, while also showing promising biological activities, offering substantial opportunities for future research.

Physicochemical Characteristics and Dyeing Properties of Novel Cellulosic Fibers Derived from Sustainable Agricultural Waste

Development of new innovative sustainable fibres from agricultural waste are in great demand these days. For the expansion of these fibres at commercial level, understanding about physicochemical properties of these fibres and specifically their dyeing behavior is essential. In this consequence, in the present study, a natural lignin-cellulosic fibers were extracted by a simplistic route, from lotus silk. The fibers were turn in to yarn by hand twisting and then natural as well as chemical dyeing was performed by the standard dyeing method established for cotton dyeing. Natural henna dye, C.I Reactive blue and indigo dye was used in the present study. Physico chemical properties and dyeing mechanism of the prepared fibers were studied and analyzed in detail in comparison with cotton cellulosic fibres. The lotus fibers were described for their organic construction and morphology by FT-IR spectroscopy and Scanning Electronic Microscopy respectively. Tensile strength, moisture regain and elongation percentage at break were also evaluated. The outcomes revealed that lotus fibers are cellulosic in nature same as cotton but with higher moisture absorption and lower crystallinity as compared to cotton fibers. Lotus fibers revealed higher color strength and color co-ordinates when compared to cotton fibers dyeing. Hollow and irregular fiber surface of lotus fibers along with higher moisture absorption and low crystallinity are the major reasons for higher chemical reactivity and absorption of dyes. The tensile strength and elongation observed in lotus fibers are suitable to be used these fibers in textile products. Lotus fibres from the agricultural waste can be a new source of sustainable textile products for future applications.

Bentonite/cerium-modified LDH composite catalyst for catalytic ozonation of high-concentration indigo carmine dye solution

This research tackles the pressing issue of high-concentration indigo carmine (IC) dye degradation, where concentrations reach as high as 6000 mg/L. We synthesized a novel catalyst comprising a bentonite-supported cerium-modified magnesium-aluminum layer double hydroxide (Mg-Al-Ce LDH) composite. Our investigation focused on the catalytic prowess of two versions of this catalyst in decolorizing and degrading the IC dye. Remarkably, these catalysts swiftly decolorized the dye solution within 20 min and achieved an impressive 95% Total Organic Carbon (TOC) removal in 60 min, significantly outperforming the 50% TOC reduction by ozonation without a catalyst. Bentonite's role as a support material was crucial, bolstering the catalysts' stability in demanding conditions. This study heralds a breakthrough in high-concentration dye waste treatment, marking a significant stride toward eco-friendly wastewater management practices.

An environmentally friendly indigo dyeing process using iron (II) gluconate as a reducing agent

This research paper aims to replace the ecologically harmful sodium dithionite traditionally used in the indigo dyeing process with the iron (II) gluconate reducing agent. The density functional theory (DFT) method using B3LYP 6- 311 G basis set was used to determine the optimized structures of iron (II) gluconate and indigo. The highest occupied molecular orbital (HOMO) energy and the lowest unoccupied molecular orbital (LUMO) energy were calculated, and the electronic properties dependent on HOMO-LUMO energies were determined. Furthermore, an ecological dyeing process using this reducing agent was studied. The influences of alkalinity, reduction temperature, and iron (II) gluconate concentration on the fulfilment of the dyeing process were inspected by measuring the obtained redox potential and the color strength of the dyed samples. A full factorial experiment was performed for statistical analysis and optimization of the dyeing process. The results revealed that the developed method is highly effective and capable of generating redox potential and dyeing quality comparable to those obtained with the conventional process employing sodium dithionite. Finally, the substitution of sodium dithionite by iron (II) gluconate reduced the wastewater load generated by the conventional dyeing process.

Investigation of the effect of different additives on the qualities, <i>in vitro</i> degradation, and rumen fermentation profile of indigo waste silage

<abstract> <p>Natural indigo dye production produces indigo waste as a by-product. Our purpose of this study was to examine the effects of calcium hydroxide (Ca(OH)<sub>2</sub>), cellulase (CE), molasses (MO), and their combinations on the silage quality, <italic>in vitro</italic> degradability, and rumen fermentation parameters of indigo waste silage. A completely randomized design (CRD) was used for the experiment. Indigo waste was chopped and ensiled in a small-scale silo with no additive (control), Ca(OH)<sub>2</sub>, MO, CE, Ca(OH)<sub>2</sub>:MO, Ca(OH)<sub>2</sub>:CE, MO:CE, and MO:CE:Ca(OH)<sub>2</sub>. After 30 days of storage, the silages were tested for quality and chemical composition, as well as an <italic>in vitro</italic> fermentation. The ruminal fluid inoculum was collected from two beef cattle with a body weight (BW) of 200±10 kg, and the inoculum had been pre-heated before being transported to the laboratory. Silage with MO, CE, or their combination increased the amount of lactic acid (<italic>p</italic> < 0.01). The silage pH was lowest in MO:CE (4.5) and was highest in Ca(OH)<sub>2</sub>:CE (10.6) in indigo waste (<italic>p</italic> < 0.01). In comparison to the control (19.5% CP), the CP content of all additives increased by 20.7% to 21.5% (<italic>p</italic> = 0.02). The addition of Ca(OH)<sub>2</sub>:MO and Ca(OH)<sub>2</sub>:CE resulted in a reduction of NDF content by 60.7% and 59.4%, respectively, in comparison to the control group (72.4%) (<italic>p</italic> < 0.01). Silage with additives had no effect on the cumulative gas production or gas kinetics, except that the constant rate of gas production for the insoluble fraction (c) was higher in MO (<italic>p</italic> = 0.03). <italic>In vitro</italic> dry matter degradability (IVDMD) was higher in CE and MO and highest in MO:CE-treated silage (<italic>p</italic> < 0.01). The <italic>in vitro</italic> organic matter degradability (IVOMD) increased in Ca(OH)<sub>2</sub>:MO compared with the control (<italic>p</italic> = 0.03). The additives alone or in their two combinations in silage reduced the ruminal ammonia-nitrogen (NH<sub>3</sub>-N) concentration (28.0 to 31.5 mg/dL) when compared to the control (32.7 mg/dL) (<italic>p</italic> < 0.01). In addition, the highest total volatile fatty acid (VFA) level was found in the silage of the MO (92.9 mmol/L) compared with the control (71.3 mmol/l) (<italic>p</italic> < 0.01). The proportion of propionic acid and butyric acid increased (<italic>p</italic> < 0.01) whereas acetic acid decreased (<italic>p</italic> < 0.01) in the rumen of silage with MO and CE. In summary, the addition of MO and CE has the potential to be used in the silage of indigo waste.</p> </abstract>

Reactivity Studies and Synthetic Strategies Towards the Preparation of New Hydrophilic Indirubin-Triazole-Based Compounds

Indirubin is an isomer of the blue dye indigo. It is widely used in Chinese medicine as part of therapy against many diseases and, thus, its skeleton becomes a promising candidate for new drug prototypes. Since it has low solubility, its properties could be improved through the insertion of hydrophilic and pharmacophoric groups, such as sugars bridged to 1,2,3-triazoles. Here, we report the synthesis of indirubin-based compounds evaluating two different routes: via the aldol condensation reaction of triazole-isatin derivatives with 3-acetoxyindole (pathway A) and reductive coupling of isatin, followed by N-propargylation of indirubin. We also performed reactivity studies guided by density functional theory (DFT) calculations (pathway B). As a demonstration, we simulate interactions with the glycogen synthase kinase 3β enzyme, which is associated with neurodegenerative diseases, through both molecular docking and molecular dynamics simulations.

Dyes and their Importance: A Review

The global market for pigments and dyes is forecast to reach 9.9 million tons and $26.53 billion by the year 2017, driven by the growth in key end-use industries. Before synthetic dyes and pigments were discovered, limited number of natural colorant has been obtained from plants, animals and minerals. The classification of colorants has become mandatory due to huge increase in kind and number of colorants. For this reason, colorants are classified based on their structure, source, color, solubility and application methods. In this chapter, dyes will be investigated in two different groups as accordance with chemical structures and application methods. The basic classification groups were determined as azo, anthraquinone, indigo, phthalocyanine, sulfur, nitro and nitroso dyes by considering their chemical structures. According to application method, they were grouped as reactive, disperse, acid, basic, direct, and vat dyes. However, the classification of pigments as organic and inorganic pigments is also regarded as an appropriate way.

CINETIC STUDY OF PHOTOCATALYTIC DEGRADATION BY THE (TIO2/UV) SYSTEM OF INDIGO CARMINE DYE IN AQUEOUS SOLUTION

The persistence of synthetic dyes in the environment and the ineffectiveness of most conventional depollution techniques have led the scientific community to turn to advanced oxidation processes for eliminating these dyes from water. The aim of this work was to experiment with heterogeneous photocatalysis in the degradation of indigo dye in aqueous solution. The catalyst used was titanium dioxide in the anatase PC 500 form, irradiated by a polychromatic ultraviolet lamp with a wavelength λ= 365 nm. This technique proved effective, with a 77% degradation rate compared with photolysis, which removed only 17% of the indigo dye under the same conditions. Also, this work showed that low-concentration solutions were easily degraded with total decolourisation of the 12 mg/L molecule after 4 hours compared with 80% elimination of the 32 mg/L solution.The study of the influence of light intensity showed an increase in the rate of degradation of the molecule when the number of lamps placed in the reactor was increased. Total degradation was observed when 4 lamps were used for 120 minutes of irradiation.

Environmental Problem Solving Through Synthetic Biology

Abstract: The text explores the multifaceted applications of synthetic biology, highlighting its role in revolutionizing various industries. It delves into the production of green biopolymers through microbial engineering, the sustainable synthesis of indigo dye, and the potential of biodesign to address environmental challenges. The mention of HGP-Write underscores the initiative's significance in advancing synthetic biology. The text emphasizes the broad impact of synthetic biology across diverse sectors, from pharmaceuticals to environmental protection, urging the need for ethical considerations in this rapidly advancing field.

Coal fly ash-supported ZnO-promoted TiO2 towards UV photocatalytic degradation of anthraquinone dye: Parametric optimization, kinetics and mechanism studies

Heterogeneous photocatalysis via combination of catalyst and UV irradiation is one of the most promising advanced oxidation processes for degradation of water-soluble organic contaminants. Herein, different photocatalysts (ZnO/CFA, TiO2/CFA, and TiO2-ZnO/CFA) were synthesized via sol-gel and impregnation techniques and applied for the degradation of acid blue 25 (AB25) dye in aqueous solution under UV light in a photoreactor. Various spectroscopic techniques (XRF, XRD, BET, FTIR, UV–vis DRS, TEM and EDS) were employed to evaluate the chemical structure, functional groups, textural, and optical properties of the binary and ternary composites. TiO2-ZnO/CFA displayed rapid degradation of AB25 as compared to ZnO/CFA and TiO2/CFA, owing to the dualistic photocatalytic sites. The prepared TiO2-ZnO/CFA composite was used in synergy with the photoreactor for photocatalytic degradation process optimization, and the optimum degradation conditions in relation to initial AB25 concentration (10 mg/L), UV light intensity (18 W/m2), flow rate (12.5 L/h), and irradiation time (150 min) as input parameters were determined using Taguchi design approach. The maximum photocatalytic degradation efficiency was 98.79±0.94% under those aforementioned conditions, indicating that the synergies between the photoreactor and the TiO2-ZnO/CFA photocatalyst resulted in the effective destruction of AB25 dye molecules. Furthermore, the spent photocatalyst was easily removed from the degraded solution and reused up to nine times. After 150 mins of UV irradiation with TiO2-ZnO/CFA photocatalyst, almost complete mineralization of AB25 solution was achieved.

A simple and rapid colorimetric detection of methanol, ethanol, and isopropanol and its application toward alcohol-based hand sanitizer quality control

ABSTRACT A practical colorimetric analysis for alcohol determination was devised using a composite of food colorants, specifically a green solution of brilliant blue FCF and tartrazine at a ratio of 1:5 v/v. This colorimetric method was characterized by its simplicity, user-friendliness, environmental compatibility, cost-effectiveness, and suitability for self-measurement through visual examination. The colorimetric procedure entails admixture 1 mL of the alcohol sample with 50 µL of the green test solution and 250 µL of a 30% NaOH solution at ambient temperature. The ensuing color changes were visually assessed within 5 min. Through color sensing, methanol, ethanol, and isopropanol were identified by the manifestation of lemon yellow, orange, and biphasic solutions, respectively. Ethanol was semi-quantified based on color sensing from green to orange, with corresponding concentration ranges. The limit of detection for both methanol and ethanol was determined to be 30% v/v. The developed method demonstrated an accuracy of 93%, with the error range of 1 − 10% v/v and standard deviation of 3.9% v/v, as confirmed by the analysis of 100 commercially available alcohol-based hand sanitizers. This methodology has the potential for further expansion to encompass a wide range of rapid colorimetric analyses of products containing alcohol, including food items, alcohol raw materials, and cosmetics.

An environmentally friendly hydrophobic deep eutectic solvent dispersive liquid liquid microextraction for spectrophotometric analysis of indigo carmine (E132)

An environmentally friendly hydrophobic deep eutectic solvent dispersive liquid liquid microextraction for spectrophotometric analysis of indigo carmine (E132)

Perbandingan Efektivitas Bioaktivator MOL Kulit Pisang Kepok (Musa paradisiaca L.) dan EM4 Dalam Pengomposan Limbah Daun Srobilanthes cusia Secara Aerob

The production process of natural indigo dye from the Strobilanthes cusia plant has solid leaf waste as a by-product from maceration residue. This waste can be used to make solid organic fertilizer. This research aims to determine the effective concentration of adding local microorganism (MOL) of kepok banana peel and EM4 to bioactivators obtain good quality compost. Composting was carried out aerobically with variations in the concentration ratio of kepok banana peel MOL and EM4 bioactivators of 1%, 2%, 3%, 4% and 5% respectively. Fertilizer quality is determined by testing the C/N ratio parameter using the Walkey & Black (C-Organic) and Kjeldahl (N-Total) methods. Color, texture and odor tests were carried out organoleptically by 5 panelists. The results showed that in the concentration range of 1-5%, the MOL kepok banana peel bioactivator was more effective than EM4, as evidenced by the lower C/N ratio of the compost. The best product was obtained from the composting process with 5% MOL kepok banana peel bioactivator with a C/N ratio of 50.04%, water content of 48.74%, blackish brown color, very crumbly texture and an earthy smell. This result does not meet the standards for compost quality according to SNI 19-7030-2004, but the physical parameters such as color, texture, odor and water content meet the standards, namely blackish brown color, very crumbly texture and smells like soil.

Indigo carmine dye for detecting urinary track damage during vaginal surgery

ObjectiveUnrecognized ureteral and bladder injury increase morbidity and mortality in gynecologic surgery. The primary objective of this study is to analyze the efficiency of a systematic intra-venous (IV) injection of carmine indigo to detect bladder injury in gynecologic vaginal surgery for benign disease. The secondary objective is to analyze the cost and use of carmine indigo. Study designA retrospective, monocentric study was conducted in a tertiary hospital between January 2018 and October 2021. All patients undergoing a vaginal surgery of hysterectomy for benign disease or anterior prolapse were systematically included. Patients can be systematically included by the automatic coding of surgery. After anesthesia, during the patient's installation, an intravenous injection of 5 mL of intravenous indigo carmine (Carmyne®) diluted in 100 mL of physiological serum was systematically administered by the anesthesia team. Intraoperative cystoscopy was performed only in cases of suspected associated ureteral injury. ResultsWe recorded 443 vaginal hysterectomies for benign disease and 95 vaginal anterior prolapse surgeries. There were 6 (1,4%) bladder injuries during vaginal hysterectomies and 1 (1,1%) bladder injury during vaginal prolapse surgery. All bladder injuries were diagnosed intraoperatively. No ureteral injury was diagnosed in this series of patients. No complication related to IV indigo carmine injection was found. In this tertiary hospital, 1085 ampoules of carmine indigo were ordered during the same period, approximatively 270 per year. The total cost to the gynecology and obstetrics department was 19,600 euros, or about 4,900 euros per year. Half of the carmine indigo was used in vaginal surgery and half in laparotomy, caesarean section and endometriosis surgery for suspected bladder or ureteral injury.