Presence Of Dicyclohexylcarbodiimide Research Articles

Electrochemical sensor based on amine- and thiol-modified multi-walled carbon nanotubes for sensitive and selective determination of uranyl ions in real water samples.

Novel selective and sensitive electrochemical sensors based on the modification of a carbon paste electrode (CPE) with novel amine- and thiol-functionalized multi-walled carbon nanotubes (MWCNT) have been developed for the detection and monitoring of uranyl ions in different real water samples. Multiwalled carbon nanotubes were grafted with 2-aminothiazole (AT/MWCNT) and melamine thiourea (MT/MWCNT) via an amidation reaction in the presence of dicyclohexyl carbodiimide (DCC) as a coupling agent. This modification for multiwalled carbon nanotubes has never been reported before. The amine and thiol groups were considered to be promising functional groups due to their high affinity toward coordination with uranyl ions. The modified multi-walled carbon nanotubes were characterized using different analytical techniques including FTIR, SEM, XPS, and elemental analysis. Subsequently, 10 wt% MT/MWCNT was mixed with 60 wt% graphite powder in the presence of 30 wt% paraffin oil to obtain a modified carbon paste electrode (MT/MWCNT/CPE). The electrochemical behavior and applications of the prepared sensors were examined using cyclic voltammetry, differential pulse anodic stripping voltammetry, and electrochemical impedance spectroscopy. The MT/MWCNT/CPE sensor exhibited a good linearity for UO22+ in the concentration range of 5.0 × 10-3 to 1.0 × 10-10 mol L-1 with low limits of detection (LOD = 2.1 × 10-11 mol L-1) and quantification (LOQ = 7 × 10-11 mol L-1). In addition, high precision (RSD = 2.7%), good reproducibility (RSD = 2.1%), and high stability (six weeks) were displayed. Finally, MT-MWCNT@CPE was successfully utilized to measure the uranyl ions in an actual water sample with excellent recoveries (97.8-99.3%). These results demonstrate that MT-MWCNT@CPE possesses appropriate accuracy and is appropriate for environmental applications.

Triazine-Based Functionalized Activated Carbon Prepared from Water Hyacinth for the Removal of Hg2+, Pb2+, and Cd2+ Ions from Water.

A novel chelating adsorbent, based on the functionalization of activated carbon (AC) derived from water hyacinth (WH) with melamine thiourea (MT) to form melamine thiourea-modified activated carbon (MT-MAC), is used for the effective removal of Hg2+, Pb2+, and Cd2+ from aqueous solution. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) theory confirm the successful functionalization of AC with the melamine thiourea chelating ligand through the amidation reaction between the carboxyl groups of oxidized activated carbon (OAC) and the amino groups of melamine thiourea (MT) in the presence of dicyclohexylcarbodiimide (DCC) as a coupling agent. The prepared MT-MAC exhibited extensive potential for the adsorption of the toxic metal ions Hg2+, Pb2+, and Cd2+ from wastewater. The MT-MAC showed high capacities for the adsorption of Hg2+ (292.6 mg·g–1), Pb2+ (237.4 mg·g–1), and Cd2+ (97.9 mg·g–1) from aqueous solution. Additionally, 100% removal efficiency of Hg2+ at pH 5.5 was observed at very low initial concentrations (25–1000 ppb).The experimental sorption data could be fitted well with the Langmuir isotherm model, suggesting a monolayer adsorption behavior. The kinetic data of the chemisorption mechanism realized by the melamine thiourea groups grafted onto the activated carbon surface have a perfect match with the pseudo-second-order (PSO) kinetic model. In a mixed solution of metal ions containing 50 ppm of each ion, MT-MAC showed a removal of 97.0% Hg2+, 68% Pb2+, 45.0% Cd2+, 17.0% Cu2+, 7.0% Ni2+, and 5.0% Zn2+. Consequently, MT-MAC has exceptional selectivity for Hg2+ ions from the mixed metal ion solutions. The MT-MAC adsorbent showed high stability even after three adsorption–desorption cycles. According to the results obtained, the use of the MT-MAC adsorbent for the adsorption of Pb2+, Hg2+, and Cd2+ metal ions from polluted water is promising.

Synthesis, antioxidant and antimicrobial activities for new 4,4'-methylenedianiline amide compounds

Free radicals are particles that have an unpaired electron. If they produced in high level in our bodies, they can produce damage to lipids, proteins, and DNA. Antioxidants are any compounds that can incorporate free radicals in a safe way, cease the reaction, and switch them to a risk-free molecule by donating a proton. On the other side, the infectious diseases are among the chief causes of death worldwide, and antimicrobial resistance has been regularly reported globally. Thus, these complications necessitate the investigation for new therapies with potential antioxidant and antimicrobial activities. This study aims to design, synthesize and evaluate the antioxidant and antimicrobial activities of new N,N'-(dialkoyl/diaroyl)-4,4'-methylenedianiline compounds. These compounds were synthesized by the reaction of carboxylic acids with 4,4'-methylenedianiline in presence of dicyclohexylcarbodiimide (DCC) as coupling agent. The structures of the synthesized compounds were characterized on the basis of the physical and spectral data. The antioxidant activity of these compounds was evaluated by testing their free radical scavenging activity of DPPH and H2O2 and their antimicrobial activity was evaluated via measuring the inhibition zones in the disk diffusion method. The tested synthesized compounds show varied antioxidant and antimicrobial activities. The hydroxyl and the amide moieties in the synthesized compound possess similar potent antioxidant activities. The fluoro-aromatic compound showed potent antibacterial and antifungal activities. While the chloro aliphatic and aromatic compounds showed only antibacterial activity. Whereas fluoro-aromatic compounds and compounds with the ether group exposed a potent antifungal activity.

Regio- and stereo-selective ring expansion of keto-aziridines to the corresponding thiomorpholines

In this research, an efficient process for the synthesis of the some novel 3-thiomorpholines from a regio- and stereo-selective reaction of ketoaziridines with 2-mercaptoacetic acid in the presence of dicyclohexyl carbodiimide is reported. A plausible mechanism has been proposed.

Melamine Thiourea Chemically Modified Activated Carbon Derived from Water Hyacinth  as an Efficient Adsorbent for the Removal of Hg(II), Pb(II) and Cd(II) Ions from Aqueous Solution

The purpose of this work was to incorporate amine and thiol groups onto the surface of activated carbon (MT-MAC) derived from water hyacinth through amidation reaction between the amino groups of melamine thiourea (MT) and the carboxyl groups of activated carbon (OAC) in presence of dicyclohexylcarbodiimide as a coupling agent. The prepared MT-MAC exhibited extensive potential for the extraction of toxic metal ions Hg(II), Pb(II) and Cd(II) from wastewater. The prepared MT-MAC was characterized by different techniques like BET, SEM, XPS, and FTIR analysis. The results displayed that the total pore volume and surface area of OAC were found to be 864.52 m2 g-1 and 0.5216 m3 g-1, respectively and decreased up on modification with melamine thiourea to 493.78 m2 g-1 and0.2916 m3 g-1.FTIR spectra confirmed the incorporation of amine and thiol groups on the surface of OAC by the appearance of new peaks at 1625 cm-1 and 3332 cm-1 corresponding to the C=O stretching vibration of the NHCO (amide), and N-H stretching vibration, respectively. XPS displayed two new peaks due to S2p and N1s in the MT-MAC survey scan. The MT-MAC adsorbent showed high capacities for the removal of Hg(II) ( 292.6 mg.g-1), Pb(II) (237.4 mg.-1) and Cd(II) (97.9 mg.g-1) from aqueous solution at pH 5.5, agitation time 60 min and 298 K.The experimental sorption data could be fitted well with Langmuir isotherm model suggesting a monolayer adsorption behavior. Chemisorption mechanism via melaminethiourea groups grafted on the surface of activated carbon is suggested based on the excellent agreement of the kinetic data with pseudo–second-order model. The MT-MAC exhibited high stability over three adsorption-desorption cycles. The results also revealed that MT-MAC is a promising adsorbent for the extraction of Hg(II), Pb(II) and Cd(II) ions from polluted water.

Comparable antibacterial effects and action mechanisms of silver and iron oxide nanoparticles on Escherichia coli and Salmonella typhimurium

The current research reports the antibacterial effects of silver (Ag) and citric acid coated iron oxide (Fe3O4) NPs on Escherichia coli wild type and kanamycin-resistant strains, as well as on Salmonella typhimurium MDC1759. NPs demonstrated significant antibacterial activity against these bacteria, but antibacterial effect of Ag NPs is more pronounced at low concentrations. Ag NPs inhibited 60–90% of S. typhimurium and drug-resistant E. coli. The latter is more sensitive to Fe3O4 NPs than wild type strain: the number of bacterial colonies is decreased ~ 4-fold. To explain possible mechanisms of NPs action, H+-fluxes through the bacterial membrane and the H+-translocating FOF1-ATPase activity of bacterial membrane vesicles were studied. N,N′-Dicyclohexylcarbodiimide (DCCD)-sensitive ATPase activity was increased up to ~ 1.5-fold in the presence of Fe3O4 NPs. ATPase activity was not detected by Ag NPs even in the presence of DCCD, which confirms the bactericidal effect of these NPs. The H+-fluxes were changed by NPs and by addition of DCCD. H2 yield was inhibited by NPs; the inhibition by Ag NPs is stronger than by Fe3O4 NPs. NPs showed antibacterial effect in bacteria studied in concentration-dependent manner by changing in membrane permeability and membrane-bound enzyme activity. The FOF1-ATPase is suggested might be a target for NPs.

Development of Novel Imaging Fluorescent Agents Bearing Anti-Inflammatory Drugs: Synthesis, Structural Characterization and Evaluation of Biological Activity

A new series of 5,6-benzocoumarin derivatives carrying anti-inflammatory drugs were synthesized via alkylamide spacers, the target to develop novel imaging fluorescent agents as useful technique to cancer early discovery. Experimentally, treatment of N-Boc-1,3-propanediamine with ethyl 5,6-benzocoumarin-3-carboxlate (III) under reflux conditions followed by hydrolyzed with CF3COOH to the corresponding primary amine (V), then treatment of derivative (V) with anti-inflammatory drugs have carboxylic group in presence of DCC (N,N'-dicyclohexylcarbodiimide) as catalyst and MeCN as solvent. The structure of the synthesized compounds was confirmed by FT-IR, NMR (1H,13C) spectral data as well as elemental analysis. The fluorescence properties study was investigated spectrophotometrically in methanol and maximum emission (λem) exhibited within range 411–436 nm, meanwhile, the quantum yields were calculated comparison to Rhodamine 6G as reference. Interestingly, the compound (III) gave a higher quantum yield (ΦF = 0.96), meanwhile, compounds (VII, VIII, IX and XI) gave reasonable quantum yields (ΦF) 0.60, 0.65, 0.78 and 0.84, respectively. All synthesized compounds were screened for their anti-AChE and antimicrobial activity. Based on the results, some of the compounds showed good activity in compared to the standard drugs.

Molecular Docking, G-QSAR Studies, Synthesis and Anticancer Screening of Some New 2-Phenazinamines as Bcr-Abl Tyrosine Kinase Inhibitors.

The computational studies on 2-phenazinamines with their protein targets have been carried out to design compounds with potential anticancer activity. This strategy of designing compounds possessing selectivity over specific tyrosine kinase has been achieved through G-QSAR and molecular docking studies. The objective of this research has been to design newer 2-phenazinamine derivatives as Bcr-Abl tyrosine kinase inhibitors by G-QSAR, molecular docking studies followed by wet lab studies along with evaluation of their anticancer potential. Computational chemistry was done by using VLife MDS 4.3 and Autodock 4.2 followed by wet lab experiments for synthesizing 2- phenazinamine derivatives. The chemical structures of ligands in 2D were drawn by employing Chemdraw 2D Ultra 8.0 and were converted into 3D. These were optimised by using semiempirical method called MOPAC. The protein structure was retrieved from RCSC protein data bank as PDB file. The binding interactions of protein and ligands were done by using PYMOL. The molecular properties of the designed compounds were predicted in silico by using Osiris property explorer. Later, we synthesized novel 13 2-phenazinamine derivatives by treating parent compound with various aldehydes in the presence of dicyclohexylcarbodiimide (DCC) and urea to afford 2-(2-chlorophenyl)-3-(phenazin-2-yl) thiazolidin-4-one and another series of derivatives synthesized with different aldehydes in the presence of p-toluylsulphonic acid, diphydropyridine and benzene sulfonyl chloride to afford benzenesulfonyl-N-(2-chlorobenzyl)-phenazin-2-amine. All the derivatives were tested for invitro anticancer activity on K562 human chronic myelogenous leukemia cell line by employing MTT assay method. The developed G-QSAR models were found to be statistically significant with respect to training (r2=0.8074), cross-validation (q2=0.6521), and external validation (pred_r2=0.5892). The best developed G-QSAR model suggested that the XlogP values of phenazinamine derivatives were found to be highly influential in determining biological activity. The standard drug was found to exhibit binding energy - 6.79 kcal/mol and the derivatives 5b and 6c exhibited binding energy of - 7.46 and - 8.51; respectively. Compounds 5b, 6c were observed to possess good lipophilicity and were found to exhibit better activity than other compounds in the series, although less than standard doxorubicin. The synthesis of these 2-phenazinamine derivatives (5a-m) is reported to be obtained from 2,4- dinitrodiphenylamine by applying appropriate synthetic route. Compounds 5b and 6c showed better cytotoxic activity against K562 cancer cell line when compared to other compounds of the series, although less than standard doxorubicin.

Rivet-Inspired Modification of Aramid Fiber by Decorating with Silica Particles to Enhance the Interfacial Interaction and Mechanical Properties of Rubber Composites.

A rivet–inspired method of decorating aramid fiber (AF) with silica particles (SiO2) is proposed to produce SiO2@AF hybrid materials that have largely enhanced interfacial interaction with the rubber matrix. AF was firstly surface-modified with polyacrylic acid (PAA) to obtain PAA–AF, and SiO2 was silanized with 3-aminopropyltriethoxysilane to obtain APES–SiO2. Then, SiO2@AF was prepared by chemically bonding APES–SiO2 onto the surface of PAA–AF in the presence of dicyclohexylcarbodiimide (DCC) and 4-dimethylaminopyridine (DMAP). With the incorporation of SiO2@AF into the rubber matrix, SiO2@AF hybrid materials with high surface roughness can play a role as ‘rivets’ to immobilize large numbers of rubber chains on the surface. The tear strength and tensile strength of rubber composite that filling 4 phr SiO2@AF are dramatically increased by 97.8% and 89.3% compared to pure rubber, respectively. Furthermore, SiO2@AF has superiority in enhancing the cutting resistance of rubber composites, in contrast with unmodified AF and SiO2. SiO2@AF is suitable to be applied as a novel reinforcing filler in rubber composites for high performance.

Synthesis and characterization of pectin-chitosan conjugate for biomedical application

BackgroundPolysaccharides are extensively used in drug delivery systems due to their ability to undergo a broad range of chemical and enzymatic reactions, forming new molecules. Among these, chitosan (CS) and pectin (PEC) are widely used for designing new conjugates and biopolymers. MethodsIn this study, we synthesized pectin-chitosan conjugate (PEC-CS) by using carbodiimide crosslinking chemistry. Pectin-N-hydroxysuccinimide ester, formed in the presence of dicyclohexylcarbodiimide under anhydrous conditions, was conjugated with chitosan by linking the free carboxyl group of PEC with the primary amino group of chitosan. ResultsFourier-transform infrared spectroscopy confirmed the formation of the PEC-CS conjugate. X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and scanning electron microscopy analyses showed that the PEC-CS conjugate is amorphous in nature, has high thermostability than those of native polymers, and has no cytotoxicity. ConclusionOur results indicated that PEC-CS conjugate can be further developed for use in drug delivery systems.

Synthesis of Methylcytisine 9-Thiocarboxamides

9-Carboxamide derivatives of the quinolizidine alkaloid methylcytisine were synthesized. The synthetic pathway included nitration-reduction according to the literature that resulted in 9-amination of the 2-pyridone core of the starting alkaloid. The obtained 9-amino derivative was converted by CS2 in Py in the presence of dicyclohexylcarbodiimide (DCC) into the corresponding isothiocyanate. The synthesized 9-isothio derivative was reacted with primary and secondary amines. The yields of the obtained 9-thiocarboxamide methylcytisine derivatives were 80–98%. The structures of the synthesized compounds were established using elemental analyses and IR, PMR, 13C NMR, and 15N NMR spectroscopy.

Polyethyleneimine Nanofibers Functionalized with Tetradentate Schiff Base Complexes of Dioxomolybdenum(VI) as Efficient Catalysts for Epoxidation of Alkenes

AbstractThree tetradentate Schiff base ligands (H2L1‐3) were prepared from the reaction of 5‐sustituted‐2‐hydroxybenzaldehydes and 3,4‐diaminobenzoic acid. The obtained ligands were reacted with molybdenyl acetylacetonate in ethanol to prepare the corresponding dioxomolybdenum(VI) complexes (MoO2L1‐3) in good yields (80‐82%). Immobilization of the abovementioned complexes on polyethyleneimine (PEI) was achieved via condensation of carboxylic functional groups of the complex with amine functional groups of the polymer in presence of dicyclohexylcarbodiimide (DCC) and 4‐dimethylaminopyridine (DMAP). The obtained hybrid materials were then converted to electrospun nanofibers and used as recyclable catalysts for the epoxidation of alkenes.

Synthesis, computational evaluation and pharmacological assessment of acetylsalicylic esters as anti-inflammatory agents

A convenient approach to the synthesis of alkyl esters of aspirin (ASA-OR) has been developed. The synthesis of ASA-OR has been realized in two steps: (1) direct esterification of salicylic acid with alcohols in the presence of dicyclohexylcarbodiimide to give alkyl salicylates (SAL-OR); (2) acetylation of SAL-OR with acetyl chloride to yield ASA-OR. Molecular mechanics simulations, performed to calculate the kinetic radii of several ASA-OR, indicated that the pentyl and hexyl acetylsalicylates possess the best properties to cross cell membranes. The in vitro biological tests demonstrate their anti-inflammatory activity, superimposable to that of aspirin. The results of our study suggest that ASA-OR may be used as anti-inflammatory drugs for topical application.

Methotrexate-conjugated mPEG–PCL copolymers: a novel approach for dual triggered drug delivery

A conjugate of the antitumor drug, methotrexate (MTX), with a diblock methoxypoly(ethylene glycol)–poly(caprolactone) (mPEG–PCL) copolymer was synthesized by the reaction of the mPEG–PCL copolymer with MTX in the presence of dicyclohexylcarbodiimide and dimethylaminopyridine.

SYNTHESIS AND ANTIMICROBIAL EVALUATION OF QUINAZOLINONE PEPTIDE DERIVATIVES

Objective: The increased microbial resistance against commercially available drugs initiated the development of novel and safe antimicrobial agents in last few decades. In this view, a series of amino acid/dipeptide derivatives of quinazolin-3(4H)-one was synthesized and was evaluated for their antimicrobial potential.Method: Synthesis of amino acid/peptide derivatives were carried out by coupling 5-(2-(2-chlorophenyl)-4-oxoquinazolin-3(4H)-yl)-2-hydroxy benzoic acid with amino acid/dipeptide methyl esters in the presence of dicyclohexylcarbodiimide and N-methylmorpholine. The chemical structures of synthesized compounds were characterized by 1H nuclear magnetic resonance and infrared spectroscopy and were screened for antibacterial activity by disc diffusion method.Results: All the synthesized derivatives exhibited moderate to significant antibacterial activity against both Gram-positive and Gram-negative bacteria. The potency of compound 5d was comparable to standard drug ciprofloxacin in all the strains of bacteria used. The compound 5a was found to be more active against Streptococcus pyogenes and Staphylococcus aureus while compound 5c against Pseudomonas aeruginosa and Escherichia coli. Conclusion: Peptide derivatives of quinazolinone are promising antimicrobial agent and can be used for the synthesis of other novel compounds.

Synteza i analiza struktury kopolimerow kwasu mlekowego i kwasu cytrynowego

The processes of condensation of citric and lactic acids carried out in melt or by coupling in the presence of dicyclohexylcarbodiimide have been investigated. The obtained products were analyzed using 1H NMR, MALDI ToF and GPC techniques. It has been shown that the condensation in melt leads generally to acomplicated mixture of lactic acid copolymers and homopolymers. However, the combining of both methods allows to obtain in high yield the copolymers with branched structure, weight-average molar masses in the range 9–27 kg/mol and Mw/Mn values between 1.3 and 2.0. By using the coupling method, amphiphilic copolymers containing ahydrophobic core composed of citric and lactic acid monomeric units and hydrophilic polyoxyethylene segments were obtained as well. These products form stable colloidal aqueous dispersions with particle diameters ranging from 50 to 500 nm.

New chalcones and thiopyrimidine analogues derived from mefenamic acid: microwave-assisted synthesis, anti-HIV activity and cytotoxicity as antileukemic agents

AbstractThe development of new HIV non-nucleoside reverse transcriptase inhibitors offers the possibility of generating structures of increased potency. To this end, coupling of mefenamic acid (4) with 4-amino-acetophenone (6) in the presence of dicyclohexylcarbodiimide and dimethylaminopyridine (DMAP) reagents afforded 4-(acetyphenyl)-2-((2,3-dimethylphenyl)amino)benzamide (7). Analogously, treatment of mefenamyl chloride (5) prepared from4with6under microwave irradiation (MWI) afforded7. A new series of substituted chalconyl-incorporated amide derivatives of mefenamic acid8–13were synthesized from condensation of7with various substituted benzaldehydes via the Claisen–Schmidt reaction. Treatment of8and11with thiourea in a basic medium afforded the thiopyrimidine analogues14and15, respectively. The newly synthesized compounds were assayed against HIV-1 and HIV-2 in MT-4 cells. Compounds9and11showed cytotoxicity values of 2.17 and 2.06 μm, respectively, against mock-infected MT-4 cells (C type adult T leukemia cells), which considered to be promising antileukemic agents.

Enhanced antibacterial effect of polypyrazole-graphene oxide composite

Besides excellent physical performances, graphene oxide (GO) has been widely acknowledged as a potential antibacterial material. Chemical modification of GO was taken out with polypyrazole by facile amidation in the presence of dicyclohexylcarbodiimide (DCC) and then generated polypyrazole-graphene oxide (FGO) nanohybrid. FGO nanohybrid showed smooth and multilayer structures by scanning electron microscopy. The value of static water contact angle of FGO is 103°, suggesting FGO was a hydrophobic material. Thermo gravimetric analysis of FGO showed a 65% mass loss up 50 to 600 °C, suggesting that FGO is a thermal stability material. Inactivation efficiency test of nominal Escherichia coli cells showed that the viability greatly decreased to 7% after 4 h incubation with FGO under 37 °C, indicating an outstanding antibacterial ability of FGO much better than that of polypyrazole and GO.

Development of nitroxide-based theranostic compounds that act both as anti-inflammatory drugs and brain redox imaging probes in MRI.

Theranostic probes provide both therapeutic and diagnostic imaging capabilities in one molecule and show significant promise for use in magnetic resonance imaging (MRI) examinations. The present study describes for the first time the synthesis and utility of nitroxide-based contrast agents exhibiting a nonsteroidal anti-inflammatory drug effect. The target theranostic probes were prepared by connecting the carboxyl group of ibuprofen or ketoprofen to the hydroxyl group of 3-hydroxymethyl-2,2,5,5-tetramethylprrolidine-1-oxyl by a condensation reaction in the presence of dicyclohexylcarbodiimide and 4-dimethylaminopyridine in dichloromethane. MRI of mouse heads after administration of either synthesized theranostic probe indicated that the probes enter the brain by passing through the blood-brain barrier (BBB), resulting in T1 contrast enhancement in mouse brain. This enhancement persisted for the duration of the half-life of about 40 min, which is longer than that obtained by most of pyrrolidine nitroxide molecules. The therapeutic capacities of these theranostic probes were examined using a lipopolysaccharide (LPS)-induced brain inflammation model. The production of nitric oxide, an inflammation marker in septic mouse brain induced by LPS, was remarkably inhibited by the addition of either synthesized probe, indicating that they also act as anti-inflammatory drugs. The present results indicate that nitroxide-based theranostic probes act as both BBB-permeable redox-sensitive contrast agents and as an anti-inflammatory drug in septic mouse brain. Copyright © 2016 John Wiley & Sons, Ltd.

Drug-conjugated PLA–PEG–PLA copolymers: a novel approach for controlled delivery of hydrophilic drugs by micelle formation

A conjugate of the antihypertensive drug, lisinopril, with triblock poly(lactic acid)–poly(ethylene glycol)–poly(lactic acid) (PLA–PEG–PLA) copolymer was synthesized by the reaction of PLA–PEG–PLA copolymer with lisinopril in the presence of dicyclohexylcarbodiimide and dimethylaminopyridine. The conjugated copolymer was characterized in vitro by hydrogen nuclear magnetic resonance (HNMR), Fourier transform infrared (FTIR), differential scanning calorimetry (DSC) and gel permeation chromatography (GPC) techniques. Then, the lisinopril conjugated PLA–PEG–PLA were self-assembled into micelles in aqueous solution. The resulting micelles were characterized further by various techniques such as dynamic light scattering (DLS) and atomic force microscopy (AFM). The results revealed that the micelles formed by the lisinopril-conjugated PLA–PEG–PLA have spherical structure with the average size of 162 nm. The release behavior of conjugated copolymer, micelles and micelles physically loaded by lisinopril were compared in different media. In vitro release study showed that in contrast to physically loaded micelles, the release rate of micelles consisted of the conjugated copolymer was dependent on pH of media where it was higher at lower pH compared to the neutral medium. Another feature of the conjugated micelles was their more sustained release profile compared to the lisinopril-conjugated copolymer and physically loaded micelles.