Diethylaminoethyl Dextran Research Articles

Transport of a model diffusion probe in polyelectrolyte-surfactant hydrogels

Interactions of biopolymeric electrolytes with oppositely charged surfactants can result in micelle-like nanocontainers capable to dissolve hydrophobic substances. These micelle-like nanostructures can solve problems with hydrophobic nature of pharmaceutically active substances and be potentially usable for medical applications. In this study, two types of hydrogels were prepared: 1) based on hyaluronan and cationic surfactant septonex (carbethoxypendecinium bromide) and 2) based on diethylaminoethyl dextran and sodium dodecylsulphate. Nile red as a dye diffusion probe was incorporated into hydrogel in their preparation and then its release into surfactant solution and physiological saline was monitored. The release of NR from hydrogels was characterized by the effective diffusion coefficients of NR and structural parameters of hydrogels. The diffusion of NR in hydrogels was dependent on the molecular weight of polyelectrolyte and the ratio between charges of polyelectrolyte and surfactant. In the case of lower ratios, a bigger part of NR was probably incorporated in “pearl necklace structure” which suppressed its mobility. The increase of concentration of surfactant was connected with higher content of NR in free micelles or micelle-like aggregates and the increase in the release of NR. The formation of bigger micelles based on NR and SDS (in comparison with micelles based on NR and septonex surfactant) resulted in their lower diffusivity.

Modulation of the electroosmotic mobility using polyelectrolyte multilayer coatings for protein analysis by capillary electrophoresis

Successive multiple ionic-polymer layers (SMIL) coatings have been often used in capillary electrophoresis due to their simplicity to implement and regenerate. However, the performances of the separation are strongly dependent on the nature of the polyelectrolyte partners used to build the SMIL coating. In this work, we investigate new couples of polyelectrolytes that were not tested before: namely, polybrene (PB), quaternized diethylaminoethyl dextran (DEAEDq) and ε-poly(lysine) (ε-PLL), as polycations, in combination with poly(acrylic acid), dextran sulfate, poly(styrenesulfonate), poly(methacrylic acid) and poly(l-lysine citramide), as polyanions. Systematic study of intra- and inter-capillaries repeatabilities/reproducibilities was performed based on the determination of migration time, separation efficiency and electroosmotic mobility. Interestingly, the electroosmotic flow was found to vary with the nature of the polycation on a broad range of electroosmotic mobility decreasing in magnitude in the order of PB>ε-PLL > DEAEDq, whatever the polyanion associated. Application of the coatings to the separation of proteins is illustrated in a 0.5 M acetic acid BGE, including CE-MS separation of ribonuclease B-glycoforms of the same mass (positional or structural isomers).

Role of β-Interferon Inducer (DEAE-Dextran) in Tumorigenesis by VEGF and NOTCH1 Inhibition along with Apoptosis Induction.

As a novel target for breast cancer, interferon inducers have found its role as anti-angiogenic agents with diethylaminoethyl dextran (DEAE-Dextran) being a molecule used for centuries as a transfection agent. Our results herein offer an explanation for the emergence of DEAE-Dextran as an anti-tumor agent for TNBC with in-depth mechanistic approach as an anti-angiogenic molecule. DEAE-Dextran has found to possess cytotoxic activity demonstrated during the various in vitro cytotoxicity assays; moreover, as an anti-oxidant, DEAE-Dextran has shown to possess excellent reactive oxygen species scavenging activity. The interferon inducing capacity of DEAE-Dextran was determined qualitatively as well as quantitatively specifically demonstrating overexpression of β-interferon. As a measure of anti-proliferative activity, DEAE-Dextran exhibited reduced ki67, p53, and PCNA levels. Also, overexpression of CK5/6 and p63 in DEAE-Dextran treated animals indicated improvement in breast cell morphology along with an improvement in cell–cell adhesion by virtue of upregulation of β-catenin and E-cadherin. Anti-angiogenic property of DEAE-Dextran was concluded by the downregulation of CD31, VEGF, and NOTCH1 both in vivo and in vitro. Further, apoptosis due to DEAE-Dextran, initially determined by downregulation of Bcl2, was confirmed with flow cytometry. Overall, results are defensive of DEAE-Dextran as an emerging anti-tumor agent with mechanisms pertaining to β-interferon induction with probable VEGF and NOTCH1 inhibition as well as apoptosis which still needs to be studied in further depth.

The role of charge in the toxicity of polymer-coated cerium oxide nanomaterials to Caenorhabditis elegans

This study examined the impact of surface functionalization and charge on ceria nanomaterial toxicity to Caenorhabditis elegans. The examined endpoints included mortality, reproduction, protein expression, and protein oxidation profiles. Caenorhabditis elegans were exposed to identical 2–5nm ceria nanomaterial cores which were coated with cationic (diethylaminoethyl dextran; DEAE), anionic (carboxymethyl dextran; CM), and non-ionic (dextran; DEX) polymers. Mortality and reproductive toxicity of DEAE-CeO2 was approximately two orders of magnitude higher than for CM-CeO2 or DEX-CeO2. Two-dimensional gel electrophoresis with orbitrap mass spectrometry identification revealed changes in the expression profiles of several mitochondrial-related proteins and proteins that are expressed in the C. elegans intestine. However, each type of CeO2 material exhibited a distinct protein expression profile. Increases in protein carbonyls and protein-bound 3-nitrotyrosine were also observed for some proteins, indicating oxidative and nitrosative damage. Taken together the results indicate that the magnitude of toxicity and toxicity pathways vary greatly due to surface functionalization of CeO2 nanomaterials.

Protein adsorption onto diethylaminoethyl dextran modified anion exchanger: Effect of ionic strength and column behavior

Abstract Our previous studies on bovine serum albumin (BSA) adsorption to diethylaminoethyl dextran (DEAE dextran, DexD, grafting-ligand) and DEAE (D, surface-ligand) modified Sepharose FF resins found that all the grafted resins (FF-DexD and FF-D-DexD) exhibited extremely fast uptake rate (effective diffusivity, De, De/D0 > 1.4), which was six times greater than the ungrafted resins (De/D0 1.1) at the their working/binding IS range. Moreover, the DEAE dextran-FF resin displayed much higher adsorption capacities and De values than commercial ungrafted resin in their working condition. Furthermore, the column results of DEAE dextran-FF resins presented higher dynamic binding capacities than and similar elution ISs with DEAE Sepharose FF to achieve similar (or even higher) recoveries suggest the excellent chromatographic column performance of the DEAE dextran-FF resins. Finally, both high recovery and purity of BSA and γ-globulin could be easily achieved using the typical DEAE dextran-FF column, FF-D60-DexD160, to separate their binary mixtures, by step gradient elution. The research has provided new insights into the practical application of the series of DEAE-dextran grafted resins in protein chromatography and proved their superiority.

Interaction between polymer capsules with hydrophobic cores and a model cellular membrane at an air–water interface

Submicrocapsules have been prepared from diethylaminoethyl dextran and xanthan gum on oil cores by ultrasonic treatment. These capsules have been modified with poly-L-lysine via electrostatic adsorption. The behavior of the capsules has been investigated at an air–water interface after their introduction into the aqueous subphase. The interaction of the capsules with a 1,2-dimyristoyl-sn-glycero-3-phosphocholine monolayer formed on the water surface (model cellular membrane) has been studied both upon their introduction under the condensed monolayer and with the use of a dilute colloidal solution of the capsules as a subphase.

PH Responsive Bioactive Lead Sulfide Nanomaterials: Protein Induced Morphology Control, Bioapplicability, and Bioextraction of Nanomaterials

Precise morphologies of pH responsive bioactive lead sulfide nanoparticles (PbS NPs) were synthesized by using industrially and environmentally important proteins like zein and lysozyme (Lys), and a bioactive polymer diethylaminoethyl dextran chloride (DEAE). Though, proteins are not known morphology control agents, zein demonstrated a fine crystal growth control of PbS NPs better than Lys as well as DEAE, and even better than conventional surfactants known for their shape control behavior. Proteins and DEAE coated NPs thus obtained were highly pH responsive in terms of a color change from light gray (at low pH) to dark brown (at high pH). Bioapplicability of coated NPs was done by subjecting them to hemolysis. Both Lys and DEAE coated NPs did not induce any significant hemolysis and demonstrated their good compatibility and usability in systemic circulation. For their industrial scale uses, different extraction methods were proposed by using other industrially important biomolecules and ionic liquids. Alginic acid and xanthan gum were excellent complexing agents for an instant extraction of Lys and DEAE coated NPs from aqueous phase. Ionic liquid exhibited excellent extraction ability in both organic as well as aqueous phases.

Plaque formation of Quesland V4 lentogenic strain of Newcastle disease virus adapted in chick embryo fibroblast cells

Vaccination is one of the important methods for preventing and controlling of the Newcastle disease in Iran. Inactivated Newcastle disease vaccine is produced in the Razi Vaccine and Serum Research Institute, Iran, and is mainly used for vaccination against Newcastle disease. Clone vaccines are used in many countries nowadays. One of the ways for cloning a virus is propagation of the virus on cell cultures to obtain discrete plaques. In this study, monolayer chick embryo fibroblast (CEF) cell cultures were prepared by a standard method. Monolayer CEF cells were used for plaque production trial. Confluent monolayer CEF cells were in tissue culture plates and inoculated with avian paramyxovirus-1/chicken/Australia/Queensland/V4/1966 (QV4) (V4 seed of Newcastle vaccine) with 109.7 50 % egg infection dose. Various dilutions of the viruses were inoculated into monolayer CEF cell cultures that were supplemented with magnesium sulfate and trypsin and agar overlay medium. No plaques were observed on CEF tissue culture plates inoculated with V4 strain without adaptation. Eight discrete large and small plaques were obtained in the 10−5 dilution of adapted viruses (titer 3 × 107 plaque-forming units (PFU)/ml) with 2–4 mm diameter at 80 h post inoculation, and in the 10−7–10−10 dilution, there was no any plaque obtained. A dilution of 10−4 produced 28 plaques (1.75 × 108 PFU/ml) but not discrete plaque, and at 10−1–10−3 dilution, plaques were too much that they were not countable. Eight various plaques at 10−5 were collected and propagated for further investigations. The present assay is a useful tool for demonstration of discrete plaques using the adapted v4 of Newcastle disease virus within 3 days on monolayer CEF cell cultures covered with modified overlay media containing magnesium ions, diethylaminoethyl dextran, and ionoagar to ascertain the purity. This technique for plaque formation by v4 of Newcastle disease virus provides a method for establishing the purity of seed stock used in the production of vaccine.

Real-time monitoring of the mechanism of ibuprofen-cationic dextran crystanule formation using crystallization process informatics system (CryPRINS)

One step aqueous melt-crystallization and in situ granulation was utilized to produce ibuprofen-cationic dextran [diethylaminoethyl dextran (Ddex)] conjugate crystanules without the use of surfactants or organic solvents. This study investigates the mechanism of in situ granulation-induced crystanule formation using ibuprofen (Ibu) and Ddex. Laboratory scale batch aqueous crystallization system containing in situ monitoring probes for particle vision measurement (PVM), UV–vis measurement and focused beam reflectance measurements (FBRM) was adapted using pre-defined formulation and process parameters. Pure ibuprofen showed nucleation domain between 25 and 64°C, producing minicrystals with onset of melting at 76°C and enthalpy of fusion (ΔH) of 26.22kJ/mol. On the other hand Ibu-Ddex crystanules showed heterogeneous nucleation which produced spherical core-shell structure. PVM images suggest that internalization of ibuprofen in Ddex corona occurred during the melting phase (before nucleation) which inhibited crystal growth inside the Ddex corona. The remarkable decrease in ΔH of the crystanules from 26.22 to 11.96kJ/mol and the presence of broad overlapping DSC thermogram suggests formation of ibuprofen-Ddex complex and crystalline-amorphous transformation. However Raman and FTIR spectra did not show any significant chemical interaction between ibuprofen and Ddex. A significant increase in dissolution efficiency from 45 to 81% within 24h and reduced burst release provide evidence for potential application of crystanules in controlled drug delivery systems. It was evident that in situ granulation of ibuprofen inhibited the aqueous crystallization process. It was concluded that in situ granulation-aqueous crystallization technique is a novel unit operation with potential application in continuous pharmaceutical processing.

Physicochemical evaluation of DEAE-Dx coated liposomes for long alkyl chain lipids

The purpose of this work was to study the potential of diethylaminoethyl dextran (DEAE-Dx) coated liposomes as drug carriers.

Surface Adsorption and Molecular Modeling of Biofunctional Gold Nanoparticles for Systemic Circulation and Biological Sustainability

Fundamental aspects of protein complex coated gold nanoparticles (Au NPs) were presented for their possible use in systemic circulation in terms of pharmaceutical formulations. For this purpose, protein complexes of bovine serum albumin (BSA), lysozyme (Lys), and zein with an industrial important bioactive polymer diethylaminoethyl dextran (DEAE) were studied in the presence of Au NPs. Surface adsorption of such complexes magnified DEAE–protein interactions which were easily monitored spectroscopically under the effect of temperature and reaction time. In vitro synthesis of Au NPs allowed a simultaneous adsorption of the DEAE–protein complex on the NP surface to achieve colloidal stability, which was dramatically influenced by the nature of the DEAE–protein complex. The DEAE–BSA complex demonstrated strong favorable mainly electrostatic interactions followed by DEAE–Lys, while DEAE–zein interactions were predominantly influenced by the hydrophobic nature of zein. At the molecular level, the interactions w...

Preparation and characterization of liposomes coated with DEAE-Dextran

Abstract Liposomes as effective drug delivery vehicles have played significant role in therapeutics. However physicochemical instability of liposomes reduces its possibilities and potentials to be used in drug delivery systems. The present work describes the stabilization of liposome via electrostatic deposition of a polycationic derivative of dextran which is Diethylaminoethyl Dextran (DEAE-Dx) on soy lecithin liposome. Liposomes were prepared by thin film hydration method. The critical vesicular concentration (CVC) of lecithin was found at 0.1% (w/v) through surface tension analysis. Zeta potential and differential scanning calorimetry (DSC) measurements were obtained to study the interaction between DEAE-Dx and liposomes. The zeta potential of liposomes changed from negative value to increasingly positive after addition of DEAE-Dx. This confirmed the coating of liposomes by DEAE-Dx. Stability of the DEAE-Dx liposome suspension was studied through particle size and zeta potential measurements over a period of 35 days. DEAE-Dx liposome suspension was found more stable than the uncoated liposomes suspension. The optimum concentration of DEAE-Dx incorporated with liposome was observed at 0.02% (w/v) compared to other examined concentration of DEAE-Dx. Encapsulation efficiency of DEAE-Dx coated liposome loaded with curcumin shows slightly higher value compared to the uncoated ones.

Formulation studies on ibuprofen sodium–cationic dextran conjugate: effect on tableting and dissolution characteristics of ibuprofen

The effect of electrostatic interaction between ibuprofen sodium (IbS) and cationic diethylaminoethyl dextran (Ddex), on the tableting properties and ibuprofen release from the conjugate tablet was investigated. Ibuprofen exhibits poor flow, compaction (tableting) and dissolution behavior due to its hydrophobic structure, high cohesive, adhesive and viscoelastic properties therefore it was granulated with cationic Ddex to improve its compression and dissolution characteristics. Electrostatic interaction and hydrogen bonding between IbS and Ddex was confirmed with FT-IR and DSC results showed a stepwise endothermic solid–solid structural transformation from racemic to anhydrous forms between 120 and 175 °C which melted into liquid form at 208.15 °C. The broad and diffused DSC peaks of the conjugate granules as well as the disappearance of ibuprofen melting peak provided evidence for their highly amorphous state. It was evident that Ddex improved the flowability and densification of the granules and increased the mechanical and tensile strengths of the resulting tablets as the tensile strength increased from 0.67 ± 0.0172 to 1.90 ± 0.0038 MPa with increasing Ddex concentration. Both tapping and compression processes showed that the most prominent mechanism of densification were particle slippage, rearrangement and plastic deformation while fragmentation was minimized. Ddex retarded the extent of dissolution in general, indicating potentials for controlled release formulations. Multiple release mechanisms including diffusion; anomalous transport and super case II transport were noted. It was concluded that interaction between ibuprofen sodium and Ddex produced a novel formulation with improved flowability, tableting and dissolution characteristics with potential controlled drug release characteristics dictated by Ddex concentration.

Poly(n-butylcyanoacrylate) Nanoparticles as Carriers for Adenosine triphosphate

ABSTRACTAdenosine triphosphate (ATP) has numerous biological functions both intra- and extracellularly, including effects on the directed migration of cells with a regenerative potential in brain tissue. Therefore, carrier systems would be of interest that would be capable to be loaded with ATP and release it in a controlled manner. In the present study, poly(n-butylcyanoacrylate) (PBCA) nanoparticles as a potential carrier system were prepared by anionic polymerization using different polymerization media, which resulted in different zeta potential values and in some cases aggregation of nanoparticles. By decorating the particle surface with positively charged diethylaminoethyl dextran, multivalent ionic interaction allowed to load ATP to the nanoparticles by adsorption. In release experiments, an ATP release over 6 hours was observed. ATP-loaded nanoparticles may thus be suitable to explore biological effects of short-term ATP delivery for biomedical applications.

Anticancer efficacy of a supramolecular complex of a 2-diethylaminoethyl-dextran-MMA graft copolymer and paclitaxel used as an artificial enzyme.

The anticancer efficacy of a supramolecular complex that was used as an artificial enzyme against multi-drug-resistant cancer cells was confirmed. A complex of diethylaminoethyl–dextran–methacrylic acid methylester copolymer (DDMC)/paclitaxel (PTX), obtained with PTX as the guest and DDMC as the host, formed a nanoparticle 50–300 nm in size. This complex is considered to be useful as a drug delivery system (DDS) for anticancer compounds since it formed a stable polymeric micelle in water. The resistance of B16F10 melanoma cells to PTX was shown clearly through a maximum survival curve. Conversely, the DDMC/PTX complex showed a superior anticancer efficacy and cell killing rate, as determined through a Michaelis–Menten-type equation, which may promote an allosteric supramolecular reaction to tubulin, in the same manner as an enzymatic reaction. The DDMC/PTX complex showed significantly higher anticancer activity compared to PTX alone in mouse skin in vivo. The median survival times of the saline, PTX, DDMC/PTX4 (particle size 50 nm), and DDMC/PTX5 (particle size 290 nm) groups were 120 h (treatment (T)/control (C), 1.0), 176 h (T/C, 1.46), 328 h (T/C, 2.73), and 280 h (T/C, 2.33), respectively. The supramolecular DDMC/PTX complex showed twice the effectiveness of PTX alone (p < 0.036). Above all, the DDMC/PTX complex is not degraded in cells and acts as an intact supramolecular assembly, which adds a new species to the range of DDS.

Electrochemical behaviour of cationic polyelectrolytes at a polarized liquid/liquid interface

The behaviours of several cationic polyelec- trolytes (chitosan; polyquaternium-4; diethylaminoethyl dextran; polyquaternium-10, and aminoacrylmethacrylate copolymer, EudragitE100) at a polarised liquid/liquid interface are analysed and compared in the present paper. Based on the analysis of the voltammetric results, it was possible to determine some of the relationships between polymer structure and the tendency to adsorb at the inter- face. It was also possible to determine the substitution degree of a polymer comprising a chitosan main chain modified with glycidyltrimethylammonium chloride, and the values obtained are in agreement with those calculated using other methodologies. Finally, we report a compara- tive study concerning the effect of cationic (chitosan) and anionic (dextran sulphate) polyelectrolytes on the com- pactness of a phospholipid film.

Formation of polyelectrolyte complexes with diethylaminoethyl dextran: Charge ratio and molar mass effect

The formation of polyelectrolyte complexes (PECs) between carboxymethyl pullulan and DEAE Dextran, was investigated, in dilute solution, with emphasis on the effect of charge density (molar ratio or pH) and molar masses. Electrophoretic mobility measurements have evidenced that insoluble PECs (neutral electrophoretic mobility) occurs for charge ratio between 0.6 (excess of polycation) and 1 (stoichiometry usual value) according to the pH. This atypical result is explained by the inaccessibility of some permanent cationic charge when screened by pH dependant cationic ones (due to the Hoffman alkylation). Isothermal titration calorimetry (ITC) indicates an endothermic formation of PEC with a binding constant around 10(5) L mol(-1). Finally asymmetrical flow field flow fractionation coupled on line with static multi angle light scattering (AF4/MALS) evidences soluble PECs with very large average molar masses and size around 100 nm, in agreement with scrambled eggs multi-association between various polyelectrolyte chains.

Quantification of in situ granulation-induced changes in pre-compression, solubility, dose distribution and intrinsic in vitro release characteristics of ibuprofen-cationic dextran conjugate crystanules.

The direct effect of intermolecular association between ibuprofen and diethylaminoethyl dextran (Ddex) and the novel 'melt-in situ granulation-crystallization' technique on the solubility, dose distribution, in vitro dissolution kinetics and pre-compression characteristics of the ibuprofen-Ddex conjugate crystanules have been investigated using various mathematical equations and statistical moments. The research intention was to elucidate the mechanisms of ibuprofen solubilization, densification and release from the conjugate crystanules as well as its dose distribution in order to provide fundamental knowledge on important physicochemical, thermodynamic and system-specific parameters which are key indices for the optimization of drug-polymer conjugate design for the delivery of poorly soluble drugs. The process of melt-in situ-granulation-crystallization reduced the solubility slightly compared with pure ibuprofen, however, the ibuprofen-Ddex conjugate crystanules exhibited increased ibuprofen solubility to a maximum of 2.47×10(-1) mM (at 1.25×10(-4) mM Ddex) and 8.72×10(-1) mM (at 6.25×10(-4) mM Ddex) at 25 and 37 °C, respectively. Beyond these concentrations of Ddex ibuprofen solubility decreased steadily due to stronger bond strength of the conjugate crystanules. The enthalpy-entropy compensation plot suggests a dominant entropy-driven mechanism of solubilization. In the same vein, the addition of Ddex increased the rate and extent of in vitro ibuprofen release from the conjugate crystanule to 100% within 168 h at Ddex concentration of 1.56×10(-4) mM, followed by a decrease with Ddex concentration. The conjugate crystanules exhibited controlled and extended-complete release profile which appeared to be dictated by the concentration of the Ddex and its strong affinity for ibuprofen. A comparison of the real experimental with the predicted data using artificial neural network shows excellent correlation between solubility and dissolution profiles (average error=0.2348%). Heckel, Kawakita, Cooper-Eaton and Kuno equations were employed to determine the mechanism of densification during tapping process. Ddex in the crystanules consistently improved particle rearrangement in the order of 2.5-7 folds compared with pure ibuprofen and stabilized ibuprofen against fragmentation during tapping process. Primary and secondary particle rearrangements were the prominent mechanisms of densification while deformation and fragmentation did not occur. Lower concentrations of Ddex below its critical granular concentration (<6.25×10(-4) mM) hindered plastic deformation and fragmentation, however, the summation of primary and secondary rearrangement parameters was greater than unity suggesting that the overall rearrangement of the conjugate crystanules cannot be explained exclusively by these two steps. This study has demonstrated the formulation of a novel ibuprofen-polymer conjugate which exhibited improved dose distribution and pre-compression characteristics as well as controlled and extended-complete release profiles - a potential drug delivery strategy for poorly soluble drugs.

Dynamic contact angle analysis of protein adsorption on polysaccharide multilayer's films for biomaterial reendothelialization.

Atherosclerosis is a major cardiovascular disease. One of the side effects is restenosis. The aim of this work was to study the coating of stents by dextran derivates based polyelectrolyte's multilayer (PEM) films in order to increase endothelialization of injured arterial wall after stent implantation. Films were composed with diethylaminoethyl dextran (DEAE) as polycation and dextran sulphate (DS) as polyanion. One film was composed with 4 bilayers of (DEAE-DS)4 and was labeled D−. The other film was the same as D− but with an added terminal layer of DEAE polycation: (DEAE-DS)4-DEAE (labeled D+). The dynamic adsorption/desorption of proteins on the films were characterized by dynamic contact angle (DCA) and atomic force microscopy (AFM). Human endothelial cell (HUVEC) adhesion and proliferation were quantified and correlated to protein adsorption analyzed by DCA for fibronectin, vitronectin, and bovine serum albumin (BSA). Our results showed that the endothelial cell response was optimal for films composed of DS as external layer. Fibronectin was found to be the only protein to exhibit a reversible change in conformation after desorption test. This behavior was only observed for (DEAE-DS)4 films. (DEAE-DS)4 films could enhance HUVEC proliferation in agreement with fibronectin ability to easily change from conformation.

Impact of in situ granulation and temperature quenching on crystal habit and micromeritic properties of ibuprofen-cationic dextran conjugate crystanules

Ibuprofen was recrystallized in the presence of aqueous solution of cationic dextran derivative, Diethylaminoethyl Dextran (Ddex) using the melt-in situ granulation-crystallization technique in order to produce a stable amorphous ibuprofen-Ddex conjugates with improved morphological, micromeritic and thermo-analytical characteristics without the use of organic solvent. Ddex was used in this study because of its ability to form conjugates with various drug molecules and enhance their physicochemical characteristics and therapeutic activities. Cationic dextrans are also biocompatible and biodegradable. Mechanism of conjugation as well as the impact of conjugation on the ibuprofen crystal habit was investigated. Gaussian type normal particle size distribution was obtained and the size of the crystals in the crystanule conjugates decreased steadily, with increasing concentration of Ddex, to a minimum of 480 nm (440-folds reduction, p<0.05, n=20) at Ddex molar concentration of 0.01 mM. FT-IR spectra showed electrostatic interaction and hydrogen bonding between ibuprofen and Ddex which was confirmed with the (1)H NMR and (13)C NMR spectra. DSC curves exhibited single peaks from the binary ibuprofen-Ddex conjugate crystanules suggesting compatibility and formation of an eutectic product. The conjugate crystanules showed broad and diffuse endothermic peaks with a glass transition temperature (T(g)) of 58.3 and 59.14°C at Ddex molar concentrations of 1.56 × 10(-4) and 3.125 × 10(-4)mM respectively confirming the existence of ibuprofen-Ddex crystanule conjugates in amorphous state. Higher concentrations of Ddex decreased T(g) steadily. TGA curves showed first order degradation at low molar concentrations of Ddex up to 3.125 × 10(-4)mM which coincides with the critical granular concentration of the crystanules while higher concentrations exhibited second order degradation profile. This study provides the basis for the development of stable amorphous drug-polymer conjugates with potential practical application in controlled and extended drug release formulations.