Mixture Of EtOH Research Articles

Tandem Imaging of Breath Ethanol and Acetaldehyde Based on Multiwavelength Enzymatic Biofluorometry.

Highly sensitive and selective imaging of human-borne volatile organic compounds (VOCs) enables an intuitive understanding of their concentrations and release sites. While multi-VOC imaging methods have the potential to facilitate step-by-step metabolic tracking and improve disease screening accuracy, no such system currently exists. In this study, we achieved simultaneous imaging of ethanol (EtOH) and acetaldehyde (AcH), the starting molecule and an intermediate metabolite of alcohol metabolism, using a multiwavelength VOC imaging system. The system employed alcohol dehydrogenase-catalyzed substrate oxidation (ADHOX) and reduction (ADHRD) reactions. The oxidation of EtOH by ADHOX in the presence of NAD+ produced NADH, which was subsequently oxidized by diaphorase (DP) with resazurin, leading to the resorufin formation, characterized by red fluorescence (excitation at 560 nm and fluorescence at 590 nm). Reduction of AcH by ADHRD consumed NADH, leading to a decrease in blue fluorescence (ex. 340 nm, fl. 490 nm). Meshes incorporating ADHOX-DP or ADHRD were arranged in tandem in front of a camera. Fluorescence images were captured, while a mixture of gaseous EtOH and AcH was applied by switching between two bandpass filters at 1 Hz. Each mesh exhibited selective responses to the target VOCs, with no significant impact on the dynamic range observed in either the single or tandem configurations (EtOH 1-300 ppm, AcH 0.2-5 ppm). The 90% response time was close after time-domain image differential analysis (EtOH = 26 s and AcH = 15 s). Furthermore, the system enabled simultaneous and quantitative imaging of EtOH and AcH concentrations in the breath after alcohol consumption. It also distinguished differences in alcohol metabolism based on the alcohol dehydrogenase 2 (ALDH2) activity, as indicated by the EtOH/AcH ratio (ALDH2 active vs nonactive: 120.9/0.71 ppm vs 129.2/1.99 ppm).

Antioxidative Potentials of Eleutherine bulbosa Bulb and Its Utilization in Topical Cosmetic Emulsion

The Eleutherine bulbosa bulb has been reported as a potent antioxidant in food. This work aims to extract the E. bulbosa bulb for use as an antioxidative agent in cosmetics. Water, 95% ethanol (EtOH), and propylene glycol (PG), which are normally used in cosmetic formulation, were employed as green and sustainable extraction solvents. EtOH and PG displayed better candidacy to extract active components from E. bulbosa bulbs than using water, and the mixture of EtOH and PG (EtOH/PG) resulted in the extract with higher bioactive compounds and biological activities compared with using EtOH or PG. The total phenolic content of the EtOH/PG extract was 87.60 ± 2.00 mgGAE/mL which was about an 18–23% increase from when using single EtOH or PG (70.91 ± 2.30, 74.05 ± 0.67 mgGAE/mL). UHPLC-ESI-QTOF-MS/MS analysis showed that the E. bulbosa bulb extracted in EtOH/PG was composed of naphthalenes, naphthoquinones, anthraquinones, myricetin, quercetin, epicatechin, catechin, epigallocatechin, and their derivatives. The ethanolic crude extract exhibited anti-elastase and anti-collagenase activity with the IC50 of 7.76 ± 0.35 and 0.53 ± 0.23 mg/mL, respectively, and was non-cytotoxic to human dermal fibroblast cells at 0.0001–1 mg/mL. The emulsion cream containing 2%(w/w) E. bulbosa bulb concentrated extract was found cosmetically stable after a one-month stability test under 4 °C, ambient temperature (30–35 °C), 45 °C, fluorescent light, and daylight. However, exposure to sunlight during daytime caused changes in the emulsion’s color with ΔE* of 3.85 ± 0.08, and at 45 °C caused the 12% decrease in DPPH activity of emulsion. The finding of this work heightens the antioxidative and safety potentials of the E. bulbosa bulb in cosmetic preparations.

Chitosan-functionalized poly(3-hydroxybutyrate) bead as a novel biosupport for palladium in the Suzuki cross-coupling reaction

The utilization of environmentally friendly biopolymer poly(3-hydroxybutyrate) (PHB) as a support for metal catalysts is an unexplored area. Herein, exploring a stable and recyclable heterogeneous palladium (Pd) catalyst based on PHB for the Suzuki cross-coupling reaction is an attractive topic. In this study, a novel hydrophobic and hydrophilic core-shell bead supported Pd catalyst was developed by using PHB particle as a hydrophobic rigid framework and hydrophilic chitosan (CS) as the surface of the supporting matrix to fix Pd nanoparticles (NPs). The results of structural characterization showed that the Pd NPs with a small average size of 2.3±0.82 nm were uniformly distributed on the surface of the PHB-CS bead with a Pd content of 0.12 wt%. This demonstrated that the PHB-CS bead created a stable coordinated environment for Pd fixation, preventing Pd leaching. Furthermore, the Pd@PHB-CS catalyst exhibited high catalytic efficiency with 99% conversion in the Suzuki reaction under mild conditions, using a solvent mixture of EtOH and H2O (1:1) for 0.5 h. It is worth noting that the catalyst exhibits excellent stability, and reusability. It can be reused five times without a significant reduction in activity while maintaining its structural integrity. The successful construction of Pd@PHB-CS will further expand the application of PHB in the field of metal catalysts and may help establish a green and environmentally friendly multifunctional platform for the development of highly recyclable heterogeneous catalysts containing metal nanoparticles.

Synthesis, Characterization, and Anticancer Activity of Phosphanegold(i) Complexes of 3-Thiosemicarbano-butan-2-one Oxime.

Four novel phosphanegold(I) complexes of the type [Au(PR3)(DMT)].PF6 (1-4) were synthesized from 3-Thiosemicarbano-butan-2-one oxime ligand (TBO) and precursors [Au(PR3)Cl], (where R = methyl (1), ethyl (2), tert-butyl (3), and phenyl (4)). The resulting complexes were characterized by elemental analyses and melting point as well as various spectroscopic techniques, including FTIR and (1H, 13C, and 31P) NMR spectroscopy. The spectroscopic data confirmed the coordination of TBO ligands to phosphanegold(I) moiety. The solution chemistry of complexes 1-4 indicated their stability in both dimethyl sulfoxide (DMSO) and a mixture of EtOH:H2O (1:1). In vitro cytotoxicity of the complexes was evaluated relative to cisplatin using an MTT assay against three different cancer cell lines: HCT116 (human colon cancer), MDA-MB-231 (human breast cancer), and B16 (murine skin cancer). Complexes 2, 3, and 4 exhibited significant cytotoxic effects against all tested cancer cell lines and showed significantly higher activity than cisplatin. To elucidate the mechanism underlying the cytotoxic effects of the phosphanegold(I) TBO complexes, various assays were employed, including mitochondrial membrane potential, ROS production, and gene expression analyses. The data obtained suggest that complex 2 exerts potent anticancer activity against breast cancer cells (MDA-MB-231) through the induction of oxidative stress, mitochondrial dysfunction, and apoptosis. Gene expression analyses showed an increase in the activity of the proapoptotic gene caspase-3 and a reduction in the activity of the antiapoptotic gene BCL-xL, which supported the findings that apoptosis had occurred.

Synthesis of Flavones through NaI‐Mediated Electrochemical Cyclization of Chalcones

AbstractA mild electrochemical oxidative cyclization for the synthesis of flavones from easy‐access 2’‐hydroxychalcones was developed using an inexpensive NaI as mediator and electrolyte under ambient temperature in a mixture of EtOH and H2O as solvent. This method was successfully applied to synthesize 26 examples of flavones from a variety of functionalized 2’‐hydroxychalcones. A gram‐scale formal synthesis of bioactive scutellarein was successfully demonstrated. Control experiments were conducted to disclose a possible indirect oxidation via in situ generation of iodine. The main advantages of this reaction include its broad substrate scope, scalability, ability to operate with benign solvent, and no requirement for strong oxidizing agents and external additives.

Novel Synthesis Strategy for the Use of Silica‐Based Composites Modified With Styrene‐Acrylic Copolymer as High‐Performance Adsorbents for Cationic Dyes Removal From Aqueous Environment

AbstractAdsorption is a reliable method for removing organic pollutants from water. This article provides data on the use of hybrid composites as adsorbents for Methylene Blue (MB) and Rhodamine 6G (R6G) uptake from aqueous solutions. The organo‐inorganic spherical particles were prepared using tetraethyl orthosilicate and a styrene‐acrylic copolymer through a one‐pot sol‐gel technique. The powder structures were characterised using various methods, including elemental analysis, acid‐base titration, zeta potential measurement, IR spectroscopy, thermogravimetric analysis, low‐temperature nitrogen adsorption, and scanning electron microscopy. The results revealed that the adsorption process demonstrated a preference for a pH of 6 in the case of MB, whereas for R6G, the optimal pH for adsorption was observed to be 7. The findings indicated that the pseudo‐second‐order model accurately described the kinetic data, while the equilibrium data aligned with the Freundlich model. The maximum adsorption capacities were determined to be 212.5 mg/g for MB and 323.1 mg/g for R6G, suggesting that both chemisorption and physical adsorption occurred on the surface of the adsorbent material. The composites were found to be regenerable with an HCl:EtOH mixture up to 3 cycles. These findings suggest that silica/styrene‐acrylic copolymer composites are promising sorbents for removing MB and R6G dyes from aqueous solutions.

Electrophoretic Deposition of Rochelle Salt Nanocrystals on Aluminum Plate

A straightforward and inexpensive electrophoretic method for obtaining environment-friendly nanocrystalline piezo layers from Rochelle salt (RS) is presented here. The electrophoretic deposition process includes the formation of nanocrystals by precipitation of Rochelle salt/water solutions in ethanol (anti-solvent method) under the influence of a high electric field. A nanoporous anodic aluminum oxide membrane is used to separate the electrochemical cell into two chambers. The composition of the RS:H2O:EtOH mixture and the spatial separation of the process of precipitation from electrophoretic deposition allow control of the nanocrystal size and the uniformity of the layer. The reaction kinetics, the morphology, and the piezo response to the resulting layers are all investigated. The best samples were obtained at RS:H2O:EtOH ratio 1:22.5:37.5. Under these conditions, the nanocrystals are preferentially oriented on the aluminum substrate and form a dense and homogeneous layer. Although the obtained structure is polycrystalline, the resulting piezo effect is 1120 pC/N, which is comparable to inorganic monocrystals and piezoceramics. This allows the use of electrophoretically deposited polycrystalline piezo layers in applications such as energy harvesting.

Alternating [ML2(MeOH)2] and [ML2(EtOH)2] layers in low-temperature ferromagnets [ML2(MeOH)2][ML2(EtOH)2] (M = CoII, NiII or CoII0.5NiII0.5)

Crystallization of Co(ii) and Ni(ii) complexes with a 3-imidazoline nitroxide derivative from a mixture of MeOH and EtOH (1 : 10) leads to the formation of complexes with an ordered alternation of supramolecular MeOH- and EtOH-containing layers.

Counteractive Effects of Choline Geranate (CAGE) ILs and Ethanol on Insulin’s Stability—A Leap Forward towards Oral Insulin Formulation

Choline geranate (CAGE) ionic liquids (ILs) stabilize insulin, thereby aiding its oral delivery, whereas ethanol (EtOH) affects its stability by disrupting the hydrophobic interactions. In this study, cognizance of the stabilization mechanism of insulin dimer in the presence of both CAGE ILs and EtOH mixtures is achieved through biased and unbiased molecular dynamics (MD) simulations. Here, two order parameters are employed to study the insulin dimer dissociation using well-tempered metadynamics (WT-MetaD). The stability of insulin is found to be strongly maintained until a 0.20 mole fraction of EtOH. Besides, higher concentrations of EtOH marginally affect the insulin stability. Moreover, geranate anions form a higher number of H-bonding interactions with water molecules, which aids insulin stabilization. Conversely, the addition of EtOH minimizes the water-mediated H-bonding interactions of geranate. Additionally, geranate traps the EtOH molecules, thereby preventing the interactions between insulin and EtOH. Furthermore, the free energy landscape (FEL) reveals the absence of dimer dissociation along with noticeable deviations in the distances R and the number of contacts Q. The dimerization free energy of insulin was calculated to be −16.1 kcal/mol at a 0.20 mole fraction of EtOH. Moreover, increments in mole fractions of EtOH effectuate a decrease in the insulin stability. Thus, the present study represents CAGE ILs as efficient insulin dimer stabilizes at low concentrations of EtOH.

Green Synthesis of Benzoimidazopyrimidine, Benzimidazoloquinazolinone, Triazolopyrimidine and Triazoloquinazolinone Derivatives Catalyzed by Oxalic Acid Dihydrate

Abstract: Benzoimidazopyrimidine, benzimidazoloquinazolinone, triazolopyrimidine, and triazoloquinazolinone derivatives were synthesized via a one-pot multi-component reaction in the presence of a catalytic amount of oxalic acid dihydrate. The reactions were performed in the mixture of EtOH:H2O or under solvent-free conditions as green media. The advantageous features of these methodologies are inexpensive starting materials and catalyst, high atom economy and good yields, and metal-free synthesis. Moreover, all the products were obtained by simple filtration, and no need for column chromatography or tedious separation procedures, which is very important in terms of reducing environmental pollutions.

Molecular simulation of adsorption and diffusion of H2 /CO2 /CO /MeOH /EtOH mixture into the zeolitic imidazolate framework ZIF-8

The adsorption and diffusion behaviors of H2, CO2, CO, MeOH, and EtOH into ZIF-8 were studied in pure and mixtures (binary and total) states by grand canonical Monte Carlo and molecular dynamics simulation, respectively. In addition, the separation of MeOH over the other guest molecules was also investigated in the mentioned mixtures. The results of molecular dynamics simulations showed that the diffusion coefficients of pure guest molecules followed the trend of H2> CO2> CO > MeOH > EtOH. Analysis of adsorption indicated that all of the guest molecules (except H2) have S-shaped adsorption isotherms with an initial low-uptake region, which can be ascribed to the cage-filling phenomenon. However, the trend of the initial sorption plateau range is CO2> CO > MeOH > EtOH. In the mixture used guest molecules, the most separation is related to the separation of MeOH from H2 and EtOH, which is the optimal separation of MeOH from H2 at pressures less than 1584 kPa and the optimal separation of MeOH from EtOH at a pressure of 10,000 kPa.

Phase Transition of n-Heptane/Ethanol Blends from Subcritical to Supercritical Conditions

In this study, the non-equilibrium evaporation and transcritical transition processes of the n-heptane/ethanol blends under the pure nitrogen condition are firstly analyzed, and a new transcritical criterion for the multi-component mixtures is suggested based on the molecular dynamics simulation. Firstly, the employed force fields for the n-heptane/ethanol blends are validated against the measured vapor-liquid equilibrium phase diagram and density. Then, the azeotropic phenomena are captured by the macroscopic distillation experiments for the n-heptane/ethanol blends. The MD simulation reveals that the near-azeotrope can occur in the thermodynamic non-equilibrium period for the 50%EtOH mixture in the nanometer scale, but not for the 12.5/25%EtOH mixtures. Because the lifetime of the small amount of ethanol molecules is smaller than the timescale of thermodynamic equilibrium in the 12.5/25%EtOH mixtures, which suppresses the near-azeotropic occurrence. This indicates that the non-equilibrium has a large effect on the near-azeotropic occurrence possibility. Besides, it is found that the increased ethanol concentration accelerates the evaporation rate of the n-heptane/ethanol blends in nanometer scale at low pressure, but shows little effect under high pressure conditions. Finally, the classical criterion with the large density gradient and little surface tension, is found to be insufficient to identify the transcritical transition. The molecular clusters with various sizes in the vicinity of high-density fluid and the short isothermal period are suggested to couple with the classical phenomenological criterion to determine the transcritical transition.

Biphenyl-Induced Superhelix in l -Phenylalanine-Based Supramolecular Self-Assembly with Dynamic Morphology Transitions

Biphenyl-Induced Superhelix in <scp>l</scp> -Phenylalanine-Based Supramolecular Self-Assembly with Dynamic Morphology Transitions

Structural features of nickel(II) mixed ligand complexes with mefenamic acid and nitrogen donor ligands

The reaction between Ni(NO3)2.6H2O and the non-steroidal anti-inflammatory mefenamic acid (2-[(2,3-dimethylphenyl)amino]benzoic acid), in the presence of various nitrogen donor ligands (imidazole, 2-methylimidazole, pyridine, and nicotinamide) have resulted in the formation of four novel mixed ligand mononuclear Ni(II) complexes. A direct one step metal-ligand complexation method was adopted in synthesizing the complexes under similar conditions using a solvent mixture of EtOH: H2O (2:1). The synthesized complexes have the general formula; [Ni(mef)2(L)2(EtOH)2] or [Ni(mef)2(L)2(H2O)2]·2H2O, where mef is mefenamato, L is the corresponding nitrogen donor ligand. The complexes were characterized by analytical and spectroscopic methods. FTIR studies supported the complex formation and indicated that the mefenamato ligand was coordinated as monodentate through the deprotonated carboxylate oxygen atom. Single-crystal X-ray diffraction studies show that all the complexes crystallize in the triclinic space group P-1. The complexes are isostructural, and Ni(II) lies in an octahedral geometry with NiN2O4 chromophore. Parallel stacking arrangement of the ligands, similar intramolecular N-H···O, and intermolecular O-H···O interactions between the mefenamato ligand and coordinated solvent dominated the connectivity pattern in the complexes. Also, intermolecular interactions depending on the coordinated nitrogen donor ligand further stabilized the structures of the complexes. Furthermore, density functional theory (DFT) study was done to obtain the Hirshfeld charges on different atoms.

One-pot three-component reaction for facile and efficient green synthesis of chromene pyrimidine-2,4-dione derivatives and evaluation of their anti-bacterial activity

A facile and highly efficient one-pot three-component synthesis of chromene pyrimidine-2,4-dione derivatives from available substrates catalyzed by heteropoly acid (H3PW12O40) is described. In this protocol, the reaction of diverse aldehydes, 4-hydroxycoumarin, and 4-amino-1,3-dimethyluracil in the mixture of EtOH / H2O (1:2) at room temperature in the presence of heteropoly acid (H3PW12O40) as a highly efficient catalyst affords the corresponding chromene pyrimidine-2,4-dione in good to excellent yields. Operational simplicity, low cost, eco-friendly with the environment, easy workup and purification, short reaction time, high yield of products, green media of the reaction and mild conditions are the advantages of this method. The in vitro antibacterial activities of title compounds were obtained against Escherichia coli (ATTC 35218) and Staphylococcus aureus (ATCC 6538) as Gram-negative and Gram-positive bacteria, respectively, and their activities were compared to gentamycin and penicillin as reference drugs.

S-Proline Covalented Silicapropyl Modified Magnetic Nanoparticles: Synthesis, Characterization, Biological and Catalytic Activity for the Synthesis of thiazolidin-4- ones.

Thiazolidinoneones are important pharmaceutical compounds because of their biological activities. Several methods for the synthesis of 4-thiazolidinones are widely reported in the literature. The main synthetic routes to synthesize 1,3-thiazolidin-4-ones involve three components reaction between amine, a carbonyl compound and thioglycolic acid. s-Proline covalented silicapropyl modified magnetic nanoparticles (Fe3O4@SiO2-Pr @s-proline) were prepared. The antibacterial activity of synthesized nanoparticles against four bacterias was investigated that showed that 30 Mg/L of synthesized nanoparticles is a suitable concentration for bacterial inhibitory. Finally, the catalytic application of the synthesized s-Proline covalented silicapropyl modified magnetic nanoparticles for the synthesis of thiazolidinones and pyrazolyl thiazolidinones under stirring in aqueous media was evaluated. All of the synthesized organic compounds were characterized by mp, FT IR, 1H NMR, 13C NMR and elemental analysis. A combination of aldehyde (1.0 mmol), thioglycolic acid (1.0 mmol), various amines (1mmol) and 0.05 g Fe3O4@SiO2propyl@L-proline, were reacted at room temperature under stirring in 10 mL water. After completion of the reaction, as indicated by TLC (4:1 hexane: ethylacetate), the reaction mixture was filtered in the presence of an effective magnetic bar to separate the nanocatalyst. The nanocatalyst was washed with a mixture of hot EtOH: H2O two times. The crude products were collected and recrystallized from ethanol, if necessary. We present a novel avenue for the synthesis of thiazolidinones in the presence of Fe3O4@SiO2-Pr @s-proline under solvent-free conditions. In conclusion, we have synthesized Fe3O4@SiO2-Pr@s-proline nanoparticles. Their biological activity against 4 bacterias was investigated. It released that 30Mg/L is the suitable concentration of synthesized nanoparticle for bacterial inhibitory. The catalytic efficiency of the catalyst was checked in the multicomponent reaction of various aldehyde, thioglycolic acid and various amines under stirring. This nanoparticle is a new organic-inorganic hybrid nanoparticle. The operational simplicity, the excellent yields of products, ease of separation and recyclability of the magnetic catalyst, waste reduction and high selectivity are the main advantages of this catalytic method. Furthermore, this new avenue is inexpensive and environmentally benign.

Synthesis of TiO2/WO3 Composite Nanofibers by a Water-Based Electrospinning Process and Their Application in Photocatalysis.

TiO2/WO3 nanofibers were prepared in a one-step process by electrospinning. Titanium(IV) bis(ammonium lactato)dihydroxide (TiBALDH) and ammonium metatungstate (AMT) were used as water-soluble Ti and W precursors, respectively. Polyvinylpyrrolidone (PVP) and varying ratios of TiBALDH and AMT were dissolved in a mixture of H2O, EtOH and CH3COOH. The as-spun fibers were then heated in air at 1 °C min−1 until 600 °C to form TiO2/WO3 composite nanofibers. Fiber characterization was done using TG/DTA, SEM–EDX, FTIR, XRD, and Raman. The annealed composite nanofibers had a diameter range of 130–1940 nm, and the results showed a growth in the fiber diameter with an increasing amount of WO3. The photocatalytic property of the fibers was also checked for methyl orange bleaching in visible and UV light. In visible light, the photocatalytic activity increased with an increase in the ratio of AMT, while 50% TiBALDH composite fibers showed the highest activity among the as-prepared fibers in UV light.

Extraction of polyphenols and synthesis of new activated carbon from spent coffee grounds

A valorization process of spent coffee grounds (SCG) was studied. Thus, a two-stage process, the first stage of polyphenols extraction and synthesis of a carbonaceous precursor and a subsequent stage of obtaining activated carbon (AC) by means of a carbonization process from the precursor of the previous stage, was performed. The extraction was carried out with a hydro-alcoholic solution in a pressure reactor, modifying time, temperature and different mixtures EtOH:H2O. To optimize the polyphenols extraction, a two-level factorial experimental design with three replicates at the central point was used. The best results were obtained by using a temperature of 80 °C during 30 min with a mixture of EtOH:H2O 50:50 (v/v). Caffeine and chlorogenic acid were the most abundant compounds in the analysed extracts, ranging from 0.09 to 4.8 mg∙g−1 and 0.06 to 9.7 mg∙g−1, respectively. Similarly, an experimental design was realized in order to analyze the influence of different variables in the AC obtained process (reaction time, temperature and KOH:precursor ratio). The best results were 1 h, 850 °C, and a mixture of 2.5:1. The obtained activated carbons exhibit a great specific surface (between 1600 m2∙g−1 and 2330 m2∙g−1) with a microporous surface. Finally, the adsorption capacity of the activated carbons was evaluated by methylene blue adsorption.

Iodination of Cytisine and Methylcytisine Alkaloids

Iodination of the 2-pyridone core of (–)-cytisine and methylcytisine by one equivalent of ICl or N-iodosuccinimide (NIS) in acidic solution gave primarily the 9-iodo derivatives although the starting alkaloid was incompletely converted. Use of an excess of the reagents under the same conditions gave 9,11-diiodo derivatives in 72 and 76% yields. 9-Iodomethylcytisine was prepared (61% yield in two steps) by treatment of methylcytisine with an excess of NIS in trifluoroacetic acid followed by deiodination of the 9,11-diiodo derivative by Zn dust in a mixture of EtOH and aqueous HCl.

Abstract 3886: Impact of nanosuspension of CZ48, a lactone stabilized camptothecin, on the biliary excretion and enterohepatic recycling of its active moiety, camptothecin

Abstract The biliary excretions of CZ48, a lactone-stabilized camptothecin (CPT), and CPT were evaluated in bile duct-cannulated SD rats after a single oral administration of CZ48 in two different types of formulations, co-solvent solution (CoS, control, in the mixture of DMSO, PEG 400, and EtOH (2:2:1, v/v/v) at 10 mg/ml) and nanosuspension (NS with stabilizers of TW 80 and F-108, sustained release of CZ48). Enterohepatic recycling was further characterized by collecting bile intermittently or continuously to modulate the recycling system in the rats. The results demonstrated that CZ48 and CPT were secreted into the bile as their parent forms with the dominant secretion of CPT as compared to CZ48. The AUCs0-12h of CPT in bile were 213.45 ± 232.09 and 250.40 ± 134.83 ng/ml*h/[mg/kg] in CoS and NS groups, respectively, which were 18.39 and 34.16 times higher than those of CZ48 (11.61 ± 7.99 ng/ml*h/[mg/kg] in the CoS group and 7.33 ± 2.22 ng/ml*h/[mg/kg] in the NS group). On the contrary, the AUCs0-12h of CZ48 in plasma were 6.10 and 6.80 times higher than those of CPT in CoS and NS groups, respectively. There was no significant impact of NS on the plasma AUCs0-12h and biliary excretions of CZ48 and CPT. Their concentrations in plasma and biliary excretions were sustained for 8 or 12 h post oral dose. Moreover, a pharmacokinetic co-model for CZ48 and CPT in plasma and bile was developed to characterize the biliary secretion and saturable process of enterohepatic recycling of CZ48 and CPT in rats. Citation Format: Diana S-L Chow, Yu Jin Kim, Dong Dong, Xiaohui Li. Impact of nanosuspension of CZ48, a lactone stabilized camptothecin, on the biliary excretion and enterohepatic recycling of its active moiety, camptothecin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3886.