One-step fabrication of biocompatible carboxymethyl cellulose polymeric particles for drug delivery systems

Preparation of nano(micro)particles from Cotinus coggygria scop. Extracts and investigation of their antimicrobial effects in vivo Caenorhabditis elegans model

Cotinus coggygria Scop. (Anacardiaceae) is traditionally used in Türkiye for wound and burn treatment. A series of nano/micro-sized polymeric particles were prepared from aqueous and ethanol extracts of Cotinus coggygria leaves by reverse micellar microemulsion polymerization. Optimization studies were conducted with the effect of the solvent/surfactant, crosslinker, and extract components and their amount. Thermal Gravimetric Analysis, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, and Zeta Potential measurement were conducted. In vitro antimicrobial microdilution method was utilized with minor modifications against Staphylococcus aureus ATCC 6538. Polymeric particles' toxicity and in vivo antimicrobial effect were evaluated on the life span Caenorhabditis elegans assay and C. elegans-S. aureus infection model, respectively. Synthesized microparticles (GS04) in vitro antimicrobial activity was investigated against S. aureus ATCC 6538. GS04 (Minimum Inhibitory Concentration = 62.5 μg/mL) microparticle was more effective against S. aureus, demonstrating no nematode survival changes at 500, 250, 125, 62.5, 31.25, and 15.625 μg/mL concentrations, achieving anti-infective effect at 250-15.625 μg/mL for GS04. Nanoparticles did not affect the colonization of S. aureus in the nematode model system. Therefore, concentrations of the selectively nontoxic anti-infective effect of synthesized nanoparticles from C. coggygria were identified for the first time against S. aureus ATCC 6538.

Kinetic and isotherm studies on the adsorption of ionic liquids from aqueous solutions by carboxymethyl cellulose modified with sodium methacrylate sulfonate

A novel carboxymethyl cellulose (CMC) graft copolymer (CMC-g-PSMAS) was successfully synthesized by grafting sodium methacrylate sulfonate (SMAS) onto CMC. The resulting CMC-g-PSMAS was used to absorb 1-allyl-3-methylimidazole chloride ([Amim]Cl) ionic liquid. The effects of different experimental factors such as monomer dosage, temperature and time on the grafting yield were systematically studied. Adsorption studies demonstrated that the adsorption equilibrium could be achieved within 60 min. The theoretical maximum adsorption capacity of CMC-g-PSMAS for [Amim]Cl reached 69.2 mg·g-1. Compared to several kinetic and isothermal models, the adsorption process of [Amim]Cl onto CMC-g-PSMAS could be well-described by the pseudo-second-order model (R2 = 0.991) and the Langmuir model (R2 = 0.999), which was a typical chemical adsorption process. Adsorption thermodynamics analyses at 25 °C revealed that the adsorption process was spontaneous (ΔG = -33.37 KJ·mol-1) and exothermic (ΔH = -56.52 KJ·mol-1). The adsorption capacity of CMC-g-PSMAS was 35.3 mg·g-1 after eight cycles, indicating its good stability and recyclability. As a consequence, CMC-g-PSMAS was efficient in the adsorption of [Amim]Cl, which could be a potential candidate for removing ionic liquids in aqueous environments.

Enzyme-induced degradation of natural and artificial linear polyanions

Synthetic and natural polymers are widely used for constructing drug delivery systems. Biocompatibility, water solubility and non-toxicity make polymers a convenient matrix for encapsulation, delivery and release of bioactive compounds. Coupling of a drug with a biodegraded polymer matrix is a promising way for a controlled drug delivery. Along this line, the degradation of the four polymers in the presence of two enzymes in aqueous solutions was investigated. The following polymers were used: natural polysaccharides, sodium alginate and sodium hyaluronate, artificial (modified) sodium carboxymethylcellulose and synthetic sodium polyacrylate (control); their degradation was caused by the addition of alginate lyase and hyaluronidase. The first enzyme only cleaved the specific alginate substrate and left three other intact. Contrastingly, the second enzyme degraded all three polysaccharides, including artificial carboxymethylcellulose, but did not degrade synthetic polyacrylate. The biodegradation of polymers was accompanied by decreasing the size of polymer particles in solution from 100 to 200 nm down to 20-30 nm; the latter are capable of removing from the body through the kidneys. The initial polysaccharides showed the negative surface charge in aqueous solution, which changed but retained negative after biodegradation. The initial and biodegraded polysaccharides demonstrated negligible cytotoxicity during long exposure period. The obtained results are valuable for the development of polymer carriers for drug encapsulation and delivery.

A review of recent advances of cellulose-based intelligent-responsive hydrogels as vehicles for controllable drug delivery system

To realize the maximum therapeutic activity of medicine and protect the body from the adverse effects of active ingredients, drug delivery systems (DDS) featured with targeted transportation sites and controllable release have captured extensive attention over the past decades. Hydrogels with unique three-dimensional (3D) porous structures present tunable capacity, controllable degradation, various stimuli sensitivity, therapeutic agents encapsulation, and loaded drugs protection properties, which endow hydrogels with bred-in-the-bone advantages as vehicles for drug delivery. In recent years, with the impressive consciousness of the "back-to-nature" concept, biomass materials are becoming the 'rising star' as the hydrogels building blocks for controlled drug release carriers due to their biodegradability, biocompatibility, and non-toxicity properties. In particular, cellulose and its derivatives are promising candidates for fabricating hydrogels as their rich sources and high availability, and various smart cellulose-based hydrogels as targeted carriers under exogenous such as light, electric field, and magnetic field or endogenous such as pH, temperature, ionic strength, and redox gradients. In this review, we summarized the main synthetic strategies of smart cellulose-based hydrogels including physical and chemical cross-linking, and illustrated the detailed intelligent-responsive mechanism of hydrogels in DDS under external stimulus. Additionally, the ongoing development and challenges of cellulose-based hydrogels in the biomedical field are also presented.

The Recent Progress of the Cellulose-Based Antibacterial Hydrogel

Cellulose-based antibacterial hydrogel has good biocompatibility, antibacterial performance, biodegradability, and other characteristics. It can be very compatible with human tissues and degradation, while its good water absorption and moisturizing properties can effectively absorb wound exudates, keep the wound moist, and promote wound healing. In this paper, the structural properties, and physical and chemical cross-linking preparation methods of cellulose-based antibacterial hydrogels were discussed in detail, and the application of cellulose-based hydrogels in the antibacterial field was deeply studied. In general, cellulose-based antibacterial hydrogels, as a new type of biomaterial, have shown good potential in antimicrobial properties and have been widely used. However, there are still some challenges, such as optimizing the preparation process and performance parameters, improving the antibacterial and physical properties, broadening the application range, and evaluating safety. However, with the deepening of research and technological progress, it is believed that cellulose-based antibacterial hydrogels will be applied and developed in more fields in the future.

Dual-functional porous and cisplatin-loaded polymethylmethacrylate cement for reconstruction of load-bearing bone defect kills bone tumor cells

Malignant bone tumors are usually treated by resection of tumor tissue followed by filling of the bone defect with bone graft substitutes. Polymethylmethacrylate (PMMA) cement is the most commonly used bone substitute in clinical orthopedics in view of its reliability. However, the dense nature of PMMA renders this biomaterial unsuitable for local delivery of chemotherapeutic drugs to limit the recurrence of bone tumors. Here, we introduce porosity into PMMA cement by adding carboxymethylcellulose (CMC) to facilitate such local delivery of chemotherapeutic drugs, while retaining sufficient mechanical properties for bone reconstruction in load-bearing sites. Our results show that the mechanical strength of PMMA-based cements gradually decreases with increasing CMC content. Upon incorporation of ≥3% CMC, the PMMA-based cements released up to 18% of the loaded cisplatin, in contrast to cements containing lower amounts of CMC which only released less than 2% of the cisplatin over 28 days. This release of cisplatin efficiently killed osteosarcoma cells in vitro and the fraction of dead cells increased to 91.3% at day 7, which confirms the retained chemotherapeutic activity of released cisplatin from these PMMA-based cements. Additionally, tibias filled with PMMA-based cements containing up to 3% of CMC exhibit comparable compressive strengths as compared to intact tibias. In conclusion, we demonstrate that PMMA cements can be rendered therapeutically active by introducing porosity using CMC to allow for release of cisplatin without compromising mechanical properties beyond critical levels. As such, these data suggest that our dual-functional PMMA-based cements represent a viable treatment option for filling bone defects after bone tumor resection in load-bearing sites.

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Dual-functional porous PMMA cements are developed by introducing CMC as both pore generator and drug vehicle for cisplatin.

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PMMA-based cements containing ≥3% CMC release sufficient amounts of chemotherapeutically active cisplatin.

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PMMA-based cements containing ≤3% CMC retain sufficient mechanical properties for bone reconstruction at load-bearing sites.

Polyethylenimine-Functionalized Nanofiber Nonwovens Electrospun from Cotton Cellulose for Wound Dressing with High Drug Loading and Sustained Release Properties

Electrospun cellulose nanofiber nonwovens have shown promise in wound dressing owing to the highly interconnected pore structure, high hydrophilicity coupled with other coveted characteristics of biodegradability, biocompatibility and renewability. However, electrospun cellulose wound dressings with loaded drugs for better wound healing have been rarely reported. In this study, a novel wound dressing with a high drug loading capacity and sustained drug release properties was successfully fabricated via electropinning of cellulose followed by polyethylenimine (PEI)-functionalization. Remarkably, the grafted PEI chains on the surface of electrospun cellulose nanofibers provided numerous active amino groups, while the highly porous structure of nonwovens could be well retained after modification, which resulted in enhanced adsorption performance against the anionic drug of sodium salicylate (NaSA). More specifically, when immersed in 100 mg/L NaSA solution for 24 h, the as-prepared cellulose-PEI nonwoven displayed a multilayer adsorption behavior. And at the optimal pH of 3, a high drug loading capacity of 78 mg/g could be achieved, which was 20 times higher than that of pristine electrospun cellulose nonwoven. Furthermore, it was discovered that the NaSA-loaded cellulose-PEI could continuously release the drug for 12 h in simulated body fluid (SBF), indicating the versatility of cellulose-PEI as an advanced wound dressing with drug carrier functionalities.

A Review on the Design and Hydration Properties of Natural Polymer-Based Hydrogels

Hydrogels are hydrophilic 3D networks that are able to ingest large amounts of water or biological fluids, and are potential candidates for biosensors, drug delivery vectors, energy harvester devices, and carriers or matrices for cells in tissue engineering. Natural polymers, e.g., cellulose, chitosan and starch, have excellent properties that afford fabrication of advanced hydrogel materials for biomedical applications: biodegradability, biocompatibility, non-toxicity, hydrophilicity, thermal and chemical stability, and the high capacity for swelling induced by facile synthetic modification, among other physicochemical properties. Hydrogels require variable time to reach an equilibrium swelling due to the variable diffusion rates of water sorption, capillary action, and other modalities. In this study, the nature, transport kinetics, and the role of water in the formation and structural stability of various types of hydrogels comprised of natural polymers are reviewed. Since water is an integral part of hydrogels that constitute a substantive portion of its composition, there is a need to obtain an improved understanding of the role of hydration in the structure, degree of swelling and the mechanical stability of such biomaterial hydrogels. The capacity of the polymer chains to swell in an aqueous solvent can be expressed by the rubber elasticity theory and other thermodynamic contributions; whereas the rate of water diffusion can be driven either by concentration gradient or chemical potential. An overview of fabrication strategies for various types of hydrogels is presented as well as their responsiveness to external stimuli, along with their potential utility in diverse and novel applications. This review aims to shed light on the role of hydration to the structure and function of hydrogels. In turn, this review will further contribute to the development of advanced materials, such as "injectable hydrogels" and super-adsorbents for applications in the field of environmental science and biomedicine.

Nanocellulose-based lightweight porous materials: A review

Nanocellulose has been widely concerned and applied in recent years. Because of its high aspect ratio, large specific surface area, good modifiability, high mechanical strength, renewability and biodegradability, nanocellulose is particularly suitable as a base for constructing lightweight porous materials. This review summarizes the preparation methods and applications of nanocellulose-based lightweight porous materials including aerogels, cryogels, xerogels, foams and sponges. The preparation of nanocellulose-based lightweight porous materials usually involves gelation and drying processes. The characteristics and influencing factors of three main drying methods including freeze, supercritical and evaporation drying are reviewed. In addition, the mechanism of physical and chemical crosslinking during gelation and the effect on the structure and properties of the porous materials in different drying methods are especially focused on. This contribution also introduces the application of nanocellulose-based lightweight porous materials in the fields of adsorption, biomedicine, energy storage, thermal insulation and sound absorption, flame retardancy and catalysis.

Recent advances in celluloses and their hybrids for stimuli-responsive drug delivery

The limitations of existing drug delivery systems (DDS) such as non-specific bio-distribution and poor selectivity have led to the exploration of a variety of carrier platforms to facilitate highly desirable and efficient drug delivery. Stimuli-responsive DDS are one of the most versatile and innovative approach to steer the compounds to the intended sites by exploiting their responsiveness to a range of various triggers. Preparation of stimuli-responsive DDS using celluloses and their derivatives offer a remarkable advantage over conventional polymer materials. In this review, we highlight on state-of-art progress in developing cellulose/cellulose hybrid stimuli-responsive DDS, which covers the preparation techniques, physicochemical properties, basic principles and, mechanisms of stimuli effect on drug release from various types of cellulose based carriers, through recent innovative investigations. Attention has been paid to endogenous stimuli (pH, temperature, redox gradient and ionic-strength) responsive DDS and exogenous stimuli (light, magnetic field and electric field) responsive DDS, where the cellulose-based materials have been extensively employed. Furthermore, the current challenges and future prospects of these DDS are also discussed at the end.

Synthesis of Biocompatible Cholesteryl-Carboxymethyl Xylan Micelles for Tumor-Targeting Intracellular DOX Delivery

Patients with cancer suffer from severe side effects and reduced life quality, as chemotherapeutic drugs are cytotoxic toward normal cells as well as toward cancer cells. In recent years, nanoparticles have been explored as targeted drug delivery systems; however, problems such as toxicity and instability prevent their practical application. Here, we report the synthesis of cholesteryl-carboxymethyl xylan (CCMX) via an esterification reaction between the carboxyl group of carboxymethyl xylan and the hydroxyl group of cholesterol to form biocompatible micelles as a vehicle for targeted drugs. With its critical micelle concentration (CMC) depending on the degree of substitution (DS) of cholesteryl and ranging from 0.0024 to 0.017 mg/mL, CCMX could self-assemble and form nanoscale micelles in aqueous media. Taking doxorubicin (DOX) as a model drug, the drug encapsulation efficiency (EE%) of CCMX-3 (DS of 0.35 for cholesteryl) reached 91.3%, and this system exhibited excellent internalization ability, as verified by tumor cellular uptake tests. The results of in vitro cytotoxicity and in vivo antitumor activity tests of nude mice demonstrated that CCMX-3/DOX micelles effectively suppressed the growth of tumor cells by maintaining the cytotoxicity of commercial DOX injection while reducing the toxicity against normal cells and increasing the survival time.

Functional Fragments of AIMP1-Derived Peptide (AdP) and Optimized Hydrosol for Their Topical Deposition by Box-Behnken Design

Aminoacyl-tRNA synthetase complex-interacting multifunctional protein 1 (AIMP1)-derived peptide (AdP) has been developed as a cosmeceutical ingredient for skin anti-aging given its fibroblast-activating (FA) and melanocyte-inhibiting (MI) functions. However, a suitable strategy for the topical delivery of AdP was required due to its low-permeable properties. In this study, FA and MI domains of AdP (FA-AdP and MI-AdP, respectively) were determined by functional domain mapping, where the activities of several fragments of AdP on fibroblast and melanocyte were tested, and a hydrosol-based topical delivery system for these AdP fragments was prepared. The excipient composition of the hydrosol was optimized to maximize the viscosity and drying rate by using Box-Behnken design. The artificial skin deposition of FA-AdP-loaded hydrosol was evaluated using Keshary-Chien diffusion cells equipped with Strat-M membrane (STM). The quantification of the fluorescent dye-tagged FA-AdP in STM was carried out by near-infrared fluorescence imaging. The optimized hydrosol showed 127-fold higher peptide deposition in STM than free FA-AdP (p < 0.05). This work suggests that FA- and MI-AdP are active-domains for anti-wrinkle and whitening activities, respectively, and the hydrosol could be used as a promising cosmetic formulation for the delivery of AdPs to the skin.

Morphology and thermal properties of clay based biocomposites

Carboxymethylcellulose/poly(ethylene glycol) (CMC/PEG) blend and CMC/PEG/montmorillonite (MMT) nanocomposites were produced by the solvent casting method. The clay, a sodium MMT, was incorporated in the polymer matrix at low weight loadings (from 1 wt% to 7 wt%). The MMT dispersion in the matrix was evaluated by X-ray diffraction, which revealed an intercalated structure of the nanocomposites. Different levels of intercalation have been detected. The changes in morphology caused by the addition of layered silicate on CMC/PEG blend were investigated by scanning electron microscopy (SEM). The SEM images of CMC/PEG blend containing 5% of MMT displayed more homogenous morphology than CMC/PEG blend. The compatibilizing performance of the filler was investigated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and Fourier transform infrared (FTIR) spectroscopy. The effect of the introduction of the clay on the crystallization temperature, melting temperature and crystallization degree of CMC/PEG revealed that clay behaved as a nucleating agent and enhanced the crystallization rate of PEG. Furthermore, it was demonstrated that the addition of a small percentage of montmorillonite (1%) was enough to improve the thermal stability of the nanocomposites.

Construction of flexible metal-organic framework (MOF) papers through MOF growth on filter paper and their selective dye capture

The conjugation of metal-organic frameworks (MOFs) with other materials is an excellent strategy for the production of advanced materials having desired properties and so appropriate applicability. In particular, the integration of MOFs with a flexible paper is expected to form valuable materials in separation technology. Here we report a simple method for the generation of MOF papers through the compact and uniform growth of MOF nanoparticles on the cellulose surface of a carboxymethylated filter paper. The resulting MOF papers show a selective capture ability for negatively charged organic dyes and they can be used for dye separation through simple filtration of a dye solution on the MOF papers. In addition, MOF papers can be reused after a simple washing process without losing their effective dye capture ability.

Screening of anionic-modified polymers in terms of stability, disintegration, and swelling behavior

This study aimed to screen the stability, disintegration, and swelling behavior of chemically modified anionic polymers. Investigated polymers were well-known and widely used staples of the pharmaceutical and medical field, namely, alginate (AL), carboxymethyl cellulose (CMC), polycarbophil (PC), and hyaluronic acid (HA). On the basis of amide bond formation between the carboxylic acid moieties of anionic polymers and the primary amino group of the modification ligand cysteine (CYS), the modified polymers were obtained. Unmodified polymers served as controls throughout all studies. With the Ellman's assay, modification degrees were determined of synthesized polymeric excipients. Stability assay in terms of erosion study at physiological conditions were performed. Moreover, water uptake of compressed polymeric discs were evaluated and further disintegration studies according to the USP were carried out to define the potential ranking. Results ranking figured out PCCYS > CMCCYS > HACYS > ALCYS in terms of water uptake capacity compared to respective controls. Cell viability assays on Caco-2 cell line as well as on RPMI 2650 (ATTC CCL30) proved modification not being harmful to those. Due to the results of this study, an intense screening of prominent anionic polymer derivate was performed in order to help the pharmaceutical research for the best choice of polymeric excipients for developments of controlled drug release systems.

Synthesis of magnetic epichlorohydrin cross-linked carboxymethyl cellulose microspheres and their adsorption behavior for methylene blue

Epichlorohydrin cross-linked carboxymethyl cellulose microspheres (ECH/CMC) obtained by inverse suspension method and magnetic Fe₃O₄ nanoparticles encasing the ECH/CMC microspheres (M-ECH/CMC) obtained by two different methods were successfully prepared and compared. Their structures and morphologies were analyzed using polarizing microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The adsorption behaviors of M1-ECH/CMC for methylene blue (MB) in the single cationic dye wastewater, the cationic/anionic dye mixture in the absence or presence of co-existed additives (salt and surfactant) wastewater, were also investigated with UV-vis spectrometer. The results showed that the magnetic Fe₃O₄ nanoparticles were loaded readily in situ into ECH/CMC by specific, chemical interactions between COO^- groups of ECH/CMC and magnetic responsive Fe₃O₄. The Langmuir isotherm and pseudo-second-order kinetic model provide best correlation with the experimental data for the adsorption of MB onto ECH/CMC and M1-ECH/CMC microspheres, while the Langmuir isotherm and pseudo-first-order kinetic model for M2-ECH/CMC. These microspheres are easily recyclable and exhibit high desorption and adsorption, which suggests that they can be applied as potential environmental adsorbents.

An ex situ approach to fabricating nanosilica reinforced polyacrylamide grafted guar gum nanocomposites as an efficient biomaterial for transdermal drug delivery application

A novel biocompatible TDDS based on nano-silica reinforced polyacrylamide grafted guar-gum nanocomposite.

Nanomedicine in Central Nervous System (CNS) Disorders: A Present and Future Prospective

Purpose: For the past few decades central nervous system disorders were considered as a major strike on human health and social system of developing countries. The natural therapeutic methods for CNS disorders limited for many patients. Moreover, nanotechnology-based drug delivery to the brain may an exciting and promising platform to overcome the problem of BBB crossing. In this review, first we focused on the role of the blood-brain barrier in drug delivery; and second, we summarized synthesis methods of nanomedicine and their role in different CNS disorder. Method: We reviewed the PubMed databases and extracted several kinds of literature on neuro nanomedicines using keywords, CNS disorders, nanomedicine, and nanotechnology. The inclusion criteria included chemical and green synthesis methods for synthesis of nanoparticles encapsulated drugs and, their in-vivo and in-vitro studies. We excluded nanomedicine gene therapy and nanomaterial in brain imaging. Results: In this review, we tried to identify a highly efficient method for nanomedicine synthesis and their efficacy in neuronal disorders. SLN and PNP encapsulated drugs reported highly efficient by easily crossing BBB. Although, these neuro-nanomedicine play significant role in therapeutics but some metallic nanoparticles reported the adverse effect on developing the brain. Conclusion: Although impressive advancement has made via innovative potential drug development, but their efficacy is still moderate due to limited brain permeability. To overcome this constraint,powerful tool in CNS therapeutic intervention provided by nanotechnology-based drug delivery methods. Due to its small and biofunctionalization characteristics, nanomedicine can easily penetrate and facilitate the drug through the barrier. But still, understanding of their toxicity level, optimization and standardization are a long way to go.

Synergy Effect of Nanocrystalline Cellulose for the Biosensing Detection of Glucose

Integrating polypyrrole-cellulose nanocrystal-based composites with glucose oxidase (GOx) as a new sensing regime was investigated. Polypyrrole-cellulose nanocrystal (PPy-CNC)-based composite as a novel immobilization membrane with unique physicochemical properties was found to enhance biosensor performance. Field emission scanning electron microscopy (FESEM) images showed that fibers were nanosized and porous, which is appropriate for accommodating enzymes and increasing electron transfer kinetics. The voltammetric results showed that the native structure and biocatalytic activity of GOx immobilized on the PPy-CNC nanocomposite remained and exhibited a high sensitivity (ca. 0.73 μA·mM⁻¹), with a high dynamic response ranging from 1.0 to 20 mM glucose. The modified glucose biosensor exhibits a limit of detection (LOD) of (50 ± 10) µM and also excludes interfering species, such as ascorbic acid, uric acid, and cholesterol, which makes this sensor suitable for glucose determination in real samples. This sensor displays an acceptable reproducibility and stability over time. The current response was maintained over 95% of the initial value after 17 days, and the current difference measurement obtained using different electrodes provided a relative standard deviation (RSD) of 4.47%.

Novel biodegradable calcium phosphate/polymer composite coating with adjustable mechanical properties formed by hydrothermal process for corrosion protection of magnesium substrate

Ceramic type coatings on metallic implants, such as calcium phosphate (Ca-P), are generally stiff and brittle, potentially leading to the early failure of the bone-implant interface. To reduce material brittleness, polyacrylic acid and carboxymethyl cellulose were used in this study to deposit two types of novel Ca-P/polymer composite coatings on AZ31 magnesium alloy using a one-step hydrothermal process. X-ray diffraction and scanning electron microscopy showed that the deposited Ca-P crystal phase and morphology could be controlled by the type and concentration of polymer used. Incorporation of polymer in the Ca-P coatings reduced the coating elastic modulus bringing it close to that of magnesium and that of human bone. Nanoindentation test results revealed significantly decreased cracking tendency with the incorporation of polymer in the Ca-P coating. Apart from mechanical improvements, the protective composite layers had also enhanced the corrosion resistance of the substrate by a factor of 1000 which is sufficient for implant application. Cell proliferation studies indicated that the composite coatings induced better cell attachment compared with the purely inorganic Ca-P coating, confirming that the obtained composite materials could be promising candidates for surface protection of magnesium for implant application with the multiple functions of corrosion protection, interfacial stress reduction, and cell attachment/cell growth promotion. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1643-1657, 2016.