Colloidal capsules: nano- and microcapsules with colloidal particle shells.

Utilizing colloidal particles for the assembly of the shell of nano- and microcapsules holds great promise for the tailor-made design of new functional materials. Increasing research efforts are devoted to the synthesis of such colloidal capsules, by which the integration of modular building blocks with distinct physical, chemical, or morphological characteristics in a capsule's shell can result in novel properties, not present in previous encapsulation structures. This review will provide a comprehensive overview of the synthesis strategies and the progress made so far of bringing nano- and microcapsules with shells of densely packed colloidal particles closer to application in fields such as chemical engineering, materials science, or pharmaceutical and life science. The synthesis routes are categorized into the four major themes for colloidal capsule formation, i.e. the Pickering-emulsion based formation of colloidal capsules, the colloidal particle deposition on (sacrificial) templates, the amphiphilicity driven self-assembly of nanoparticle vesicles from polymer-grafted colloids, and the closely related field of nanoparticle membrane-loading of liposomes and polymersomes. The varying fields of colloidal capsule research are then further categorized and discussed for micro- and nano-scaled structures. Finally, a special section is dedicated to colloidal capsules for biological applications, as a diverse range of reports from this field aim at pharmaceutical agent encapsulation, targeted drug-delivery, and theranostics.

Amino-Functionalized Ceramic Capillary Membranes for Controlled Virus Retention.

A straightforward chemical functionalization strategy using aminosilanes for high-flux yttria-stabilized zirconia capillary membranes is presented (macroporous, d50 = 144 nm, open porosity =49%, membrane flux ∼150 L/(m(2)hbar)). Three different aminosilanes with one, two or three amino groups per silane molecule, namely 3-aminopropyltriethoxysilane (APTES), N-(2-aminoethyl)-3-aminopropyltriethoxysilane (AE-APTES) and N-(3-trimethoxysilylpropyl)diethylenetriamine (TPDA), are used to generate the amino-functionalized membranes. With a higher number of amino groups per silane molecule increased loading capacities between 0.44 and 1.01 accessible amino groups/nm(2) membrane are achieved. Streaming potential measurements confirm that the zeta-potential of the membrane surface is converted from negative (non-functionalized) to positive (amino-functionalized). By operation in dead-end filtration mode using the model virus MS2 (diameter = 25 nm, IEP = 3.9) the virus retention capacity of the amino-functionalized membranes is significantly increased and log reduction values (LRVs) of up to 9.6 ± 0.3 (TPDA) are obtained whereas a LRV < 0.3 is provided by the non-functionalized membranes. Long-term dead-end filtration experiments for 1 week reveal a high stability of immobilized aminosilanes (TPDA), being robust against leaching. By iterative backflushing with desorption buffer MS2-loaded membranes are successfully regenerated being reusable for a new filtration cycle. The presented functionalization platform is highly promising for controlled virus retention.

Effect of Collagen Nanofibers and Silanization on the Interaction of HaCaT Keratinocytes and 3T3 Fibroblasts with Alumina Nanopores.

During wound healing, a complex cascade of cellular and molecular events occurs, which is governed by topographical and biochemical cues. Therefore, optimal tissue repair requires scaffold materials with versatile structural and biochemical features. Nanoporous anodic aluminum oxide (AAO) membranes exhibit good biocompatibility along with customizable nanotopography and antimicrobial properties, which has brought them into the focus of wound treatment. However, despite their good permeability, such bioinert ceramic nanopores cannot actively promote cell growth as they lack biochemical cues to support specific ligand-receptor interactions. Therefore, we modified AAO nanopores with the biochemical features of collagen nanofibers or amino groups provided by silanization with (3-aminopropyl)triethoxysilane (APTES) to design a permeable scaffold material that can additionally promote cell adhesion. Viability assays revealed that the metabolic activity of both 3T3 fibroblasts and HaCaT keratinocytes on bare and silanized AAO pores was comparable to glass controls until 72 h. Interestingly, both cell types showed a reduced proliferation on AAO with collagen nanofibers. Nevertheless, scanning electron and fluorescence microscopy revealed that 3T3 fibroblasts exhibited a well-spread morphology with filopodia attached to the nanoporous surface of the underlying AAO membranes or nanofibrous collagen networks, thus indicating a close interaction with the composites. Keratinocytes, although growing in clusters on bare and APTES-modified AAO, also adhered well on collagen-modified AAO membranes. When in contact with Escherichia coli suspensions for 20 h, the AAO membranes successfully prevented bacteria penetration irrespective of the biochemical functionalization. In summary, both functionalization strategies have high potential to specifically control molecular signaling and cell migration to further develop alumina nanopores for wound healing.

Janus nanoparticles designed for extended cell surface attachment.

In this study, we present Janus nanoparticles that are designed for attaching to a eukaryotic cell surface with minimal cell uptake. This contrasts the rapid uptake via various endocytosis pathways that non-passivated isotropic particles usually encounter. Firmly attaching nanoparticles onto cell surfaces for extended periods of time can be a powerful new strategy to employ functional properties of nanoparticles for non-invasive interrogation and manipulation of biological systems. To this end, we synthesized rhodamine-doped silica (SiO2) nanoparticles functionalized with 1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE) on one hemisphere of the nanoparticle surface and high-molecular-weight long-chain poly(ethylene glycol) on the other one using the wax-Pickering emulsion technique. Nanoparticle localization was studied with NIH 3T3 rat fibroblasts in vitro. In these studies, the Janus nanoparticles adhered to the cell surface and, in contrast to isotropic control particles, only negligible uptake into the cells was observed, even after 24 h of incubation. In order to characterize the potential endocytosis pathway involved in the uptake of the Janus nanoparticles in more detail, fibroblasts and nanoparticles were incubated in the presence or absence of different endocytosis inhibitors. Our findings indicate that the Janus particles are not affected by caveolae- and receptor-mediated endocytosis and the prolonged attachment of the Janus nanoparticles is most likely the result of an incomplete macropinocytosis process. Consequently, by design, these Janus nanoparticles have the potential to firmly anchor onto cell surfaces for extended periods of time and might be utilized in various biotechnological and biomedical applications like cell surface tagging, magnetic manipulation of the cell membrane or non-invasive drug and gene delivery.

Microbial fuel cell performance of graphitic carbon functionalized porous polysiloxane based ceramic membranes.

Proton-conducting porous ceramic membranes were synthesized via a polymer-derived ceramic route and probed in a microbial fuel cell (MFC). Their chemical compositions were altered by adding carbon allotropes including graphene oxide (GO) and multiwall carbon nanotubes into a polysiloxane matrix as filler materials. Physical characteristics of the synthesized membranes such as porosity, hydrophilicity, mechanical stability, ion exchange capacity, and oxygen mass transfer coefficient were determined to investigate the best membrane material for further testing in MFCs. The ion exchange capacity of the membrane increased drastically after adding 0.5 wt% of GO at an increment of 9 fold with respect to that of the non-modified ceramic membrane, while the oxygen mass transfer coefficient of the membrane decreased by 52.6%. The MFC operated with this membrane exhibited a maximum power density of 7.23 W m-3 with a coulombic efficiency of 28.8%, which was significantly higher than the value obtained using polymeric Nafion membrane. Hence, out of all membranes tested in this study the GO-modified polysiloxane based ceramic membranes are found to have a potential to replace Nafion membranes in pilot scale MFCs.

Supercritical CO2 impregnation of PLA/PCL films with natural substances for bacterial growth control in food packaging.

Biodegradable polymers with antibacterial properties are highly desirable materials for active food packaging applications. Thymol, a dietary monoterpene phenol with a strong antibacterial activity is abundant in plants belonging to the genus Thymus. This study presents two approaches for supercritical CO2 impregnation of poly(lactic acid)(PLA)/poly(ε-caprolactone)(PCL) blended films to induce antibacterial properties of the material: (i) a batch impregnation process for loading pure thymol, and (ii) an integrated supercritical extraction-impregnation process for isolation of thyme extract and its incorporation into the films, operated in both batch or semi-continuous modes with supercritical solution circulation. The PCL content in films, impregnation time and CO2 flow regime were varied to maximize loading of the films with thymol or thyme extract with preserving films' structure and thermal stability. Representative film samples impregnated with thymol and thyme extract were tested against Gram (-) (Escherichia coli) and Gram(+) (Bacillus subtilis) model strains, by measuring their metabolic activity and re-cultivation after exposure to the films. The film containing thymol (35.8 wt%) showed a strong antibacterial activity leading to a total reduction of bacterial cell viability. Proposed processes enable fast, controlled and organic solvent-free fabrication of the PLA/PCL films containing natural antibacterial substances at moderately low temperature, with a compact structure and a good thermal stability, for potential use as active food packaging materials.

Surface functionalization of Bioglass-derived porous scaffolds.

Like standard tissue culture plates, tissue engineering scaffolds can be chemically treated to couple proteins without losing the conformation and thus biological function of the proteins; a process called surface functionalization. In this work, the surface of novel 45S5 Bioglass-derived foam-like scaffolds, which exhibit adequate mechanical stability and tailorable bioresorbability, have been modified by applying 3-aminopropyl-triethoxysilane. The efficiency and stability of the surface modification were satisfactorily and quantitatively assessed by X-ray photoemission spectroscopy. It was also found that treatment in buffered (pH 8) water solution at 80 degrees C for 4h, applied during the surface functionalization procedure, accelerated the bioreactive kinetics of the scaffolds, i.e. the transition of the relatively bioinert but mechanically competent crystalline structure of the struts to a biodegradable but mechanically weak amorphous network during immersion in simulated body fluid. Thus the aqueous heat treatment is confirmed to be an important factor that must be considered in the design of these Bioglass-derived glass-ceramic scaffolds. Possible mechanisms responsible for the accelerated bioreactivity are proposed.

Combined effect of magnesia and zirconia on the bioactivity of calcium silicate ceramics at C\S ratio less than unity.

This paper describes the effect of magnesia in the presence of zirconia on the bioactivity, microstructure and physico-mechanical properties of calcium silicate composition adjusted at calcia/silica ratio(C/S) of 0.5. A mixture from calcium carbonate and silica was conducted at C/S of 0.5. 20wt.% of magnesia and 5-25wt.% of ZrO2 were added. Each mixture was mixed with ethanol in a planetary ball mill, dried, formed and fired at a temperature of 1325±5°C. Phase composition, FE-SEM, and physico-mechanical properties of the fired specimens were determined and explained. The in vitro bioactivities of these specimens were investigated by analysis of their abilities to form apatite in the simulated body fluid (SBF) for a short time (7days) using SEM-EDS. The findings indicated that the surface of the specimens containing 5 and 15wt.% ZrO2 were completely covered by single and multilayered hydroxyapatite (HA) precipitate typical to "cauliflower" morphology, respectively. The surface of the specimen containing 25wt.% ZrO2 did not cover, but there are some scattered HA precipitate. The differences among the results were rationalized based on the phase composition. Vickers hardness and fracture toughness of the specimens of highly promised bioactivity were 2.32-2.57GPa and 1.80-1.50MPa. m1/2, respectively. The properties of these specimens are similar to the properties of human cortical bone. Consequently, these composites might be used as bone implant materials.

Enhanced cell adhesion on bioinert ceramics mediated by the osteogenic cell membrane enzyme alkaline phosphatase.

Functional bone and dental implant materials are required to guide cell response, offering cues that provide specific instructions to cells at the implant/tissue interface while maintaining full biocompatibility as well as the desired structural requirements and functions. In this work we investigate the influence of covalently immobilized alkaline phosphatase (ALP), an enzyme involved in bone mineralization, on the first contact and initial cell adhesion. To this end, ALP is covalently immobilized by carbodiimide-mediated chemoligation on two highly bioinert ceramics, alpha-alumina (Al2O3) and yttria-stabilized zirconia (Y-TZP) that are well-established for load-bearing applications. The physicochemical surface properties are evaluated by profilometry, zeta potential and water contact angle measurements. The initial cell adhesion of human osteoblasts (HOBs), human osteoblast-like cells (MG-63) and mesenchymal stromal cells (hMSCs) was investigated. Cell adhesion was assessed at serum free condition via quantification of percentage of adherent cells, adhesion area and staining of the focal adhesion protein vinculin. Our findings show that after ALP immobilization, the Al2O3 and Y-TZP surfaces gained a negative charge and their hydrophilicity was increased. In the presence of surface-immobilized ALP, a higher cell adhesion, more pronounced cell spreading and a higher number of focal contact points were found. Thereby, this work gives evidence that surface functionalization with ALP can be utilized to modify inert materials for biological conversion and faster bone regeneration on inert and potentially load-bearing implant materials.

Lysozyme and bovine serum albumin adsorption on uncoated silica and AlOOH-coated silica particles: the influence of positively and negatively charged oxide surface coatings.

The adsorption of lysozyme and bovine serum albumin on silica and AlOOH-coated silica particles-representing negatively and positively charged oxide surfaces-was investigated. The protein-treated uncoated and completely AlOOH-coated silica particles were characterized by zeta potential analysis and UV/VIS spectroscopy. It was found that at pH 7 a protein oppositely charged to the oxide surface adsorbs in significantly higher amounts. In contrast, proteins of the same charge did not or only in very low amounts adsorbed on an oxide surface. As both oxide surfaces were measured to be very hydrophilic it can be concluded that electrostatic interactions dominate the adsorption process at the investigated experimental conditions. The pH regions where the proteins interact via attractive and repulsive coulomb interaction with the particular oxide surfaces were calculated and outlined.

Effect of silica on porosity, strength, and toughness of pressureless sintered calcium phosphate-zirconia bioceramics.

The preparation of dense, high-strength calcium phosphate-zirconia (CaP-ZrO2) composed bioceramics is realized via versatile pressureless sintering by adding silica nanoparticles. Two different weight ratios of HAp:ZrO2, 9:1 and 1:1, are used with varying silica contents from 5 to 20 wt%. After sintering at 1200 °C, the phase composition, microstructure, porosity, biaxial bending strength, and fracture toughness as well as SBF in vitro bioactivity are characterized. We show that the addition of silica altered the crystal phase composition, inhibiting the formation of non-favourable cubic ZrO2. Furthermore, SiO2 addition leads to an increase of the biaxial bending strength, and the fracture toughness of CaP-ZrO2-containing materials. With the addition of 20 wt% silica we find the highest characteristic strength (268 MPa) and toughness (2.3 ± 0.1 MPam(0.5)) at <1% porosity. Both mechanical properties are 2 times higher than those of pure hydroxyapatite. At the same time we observe for the very same composition similar bioactivity to that of pure hydroxyapatite.

A mild one-pot process for synthesising hydroxyapatite/biomolecule bone scaffolds for sustained and controlled antibiotic release.

The release of active molecules or the control of nosocomial infections for improved osteoinduction is ideally addressed by a bone substitute material. For this purpose, the feasibility of a mild one-pot process is probed for incorporating directly active proteins and antibiotics in a hydroxyapatite (HAp) based scaffold. The effect of two serum model proteins, bovine serum albumin (BSA) and fibrinogen (FIB), on the microstructure, on selected mechanical properties as well as on degradation behaviour and on protein release are investigated. By protein incorporation, the porosity can be adjusted between 54 and 70% especially due to the foaming ability of BSA. The addition of 5 wt% FIB doubles the biaxial flexural strength up to 6 MPa in comparison to samples without proteins (3 MPa). Protein release experiments show that a rapid release takes place within the first days (between around 3% for FIB and 38% for BSA). As a possible application for osteomyelitis treatment, vancomycin and gentamicin were subsequently added instead of proteins to study their release behaviour and their antibacterial activity, respectively. A controlled antibiotic release was observed for a period of 18 d. By varying the protein type, mixture and quantity, the mechanical strength porosity as well as the protein release and calcium solubility can be controlled. Our studies underpin the suitability of this mild one-pot process as a promising simple-to-use platform for controlled local drug release and bone treatment.

Silver nanoparticle-doped zirconia capillaries for enhanced bacterial filtration.

Membrane clogging and biofilm formation are the most serious problems during water filtration. Silver nanoparticle (Agnano) coatings on filtration membranes can prevent bacterial adhesion and the initiation of biofilm formation. In this study, Agnano are immobilized via direct reduction on porous zirconia capillary membranes to generate a nanocomposite material combining the advantages of ceramics being chemically, thermally and mechanically stable with nanosilver, an efficient broadband bactericide for water decontamination. The filtration of bacterial suspensions of the fecal contaminant Escherichia coli reveals highly efficient bacterial retention capacities of the capillaries of 8 log reduction values, fulfilling the requirements on safe drinking water according to the U.S. Environmental Protection Agency. Maximum bacterial loading capacities of the capillary membranes are determined to be 3×10(9)bacterialcells/750mm(2) capillary surface until back flushing is recommendable. The immobilized Agnano remain accessible and exhibit strong bactericidal properties by killing retained bacteria up to maximum bacterial loads of 6×10(8)bacterialcells/750mm(2) capillary surface and the regenerated membranes regain filtration efficiencies of 95-100%. Silver release is moderate as only 0.8% of the initial silver loading is leached during a three-day filtration experiment leading to average silver contaminant levels of 100µg/L.

Enzyme-assisted calcium phosphate biomineralization on an inert alumina surface.

In this study a bioinspired approach to induce self-mineralization of bone-like material on alumina surfaces is presented. The mineralizing enzyme alkaline phosphatase (ALP) is covalently immobilized by a carbodiimide-mediated chemoligation method. The enzymatic activity of immobilized ALP and its mineralization capability are investigated under acellular conditions as well as in the presence of human bone cells. Analytical, biochemical and immunohistochemical characterization show that ALP is efficiently immobilized, retains its activity and can trigger calcium phosphate mineralization on alumina at acellular conditions. In vitro cell tests demonstrate that ALP-functionalized alumina clearly boosts and enhances bone cell mineralization. Our results underpin the great potential of ALP-functionalized alumina for the development of bioactive surfaces for applications such as orthopaedic and dental implants, enabling a fast and firm implant osseointegration.

Synthesis and mechanical evaluation of Sr-doped calcium-zirconium-silicate (baghdadite) and its impact on osteoblast cell proliferation and ALP activity.

For the first time the successful preparation of Sr doped baghdadite (Ca3-x Sr x ZrSi2O9 x = 0.1 and 0.75) is shown. Sr-doped as well as pure baghdadite are prepared via a versatile solid-state synthesis and conventional sintering at 1400 °C. XRD measurements and crystal structure refinements reveal that a substitution of Ca atoms with Sr and a high purity (>99%) is achieved. The physical, mechanical, and biological properties of these novel bioceramics are presented in relation to the dopant concentration. Incorporating Sr into the baghdadite crystal caused only minor changes to the grain size and the mechanical properties. The characteristic strength ranges from 145 to 168 MPa and a Weibull modulus of 4.9 to 9.2 is observed. Other mechanical properties like fracture toughness and hardness vary from 1.23 ± 0.07 MPam(0.5) to 1.31 ± 0.12 MPam(0.5) and 7.3 ± 0.6 GPa to 8.0 ± 0.7 GPa, respectively. The in vitro cellular response of human osteoblasts showed an increase in the cell proliferation and a significantly higher alkaline phosphatase (ALP) activity with an increase in the Sr content. From the improved biological properties and the suitable mechanical performance we conclude that this material is a highly promising candidate for bone replacement material and bioactive implant coatings.

Mixed zirconia calcium phosphate coatings for dental implants: tailoring coating stability and bioactivity potential.

Enhanced coating stability and adhesion are essential for long-term success of orthopedic and dental implants. In this study, the effect of coating composition on mechanical, physico-chemical and biological properties of coated zirconia specimens is investigated. Zirconia discs and dental screw implants are coated using the wet powder spraying (WPS) technique. The coatings are obtained by mixing yttria-stabilized zirconia (TZ) and hydroxyapatite (HA) in various ratios while a pure HA coating served as reference material. Scanning electron microscopy (SEM) and optical profilometer analysis confirm a similar coating morphology and roughness for all studied coatings, whereas the coating stability can be tailored with composition and is probed by insertion and dissections experiments in bovine bone with coated zirconia screw implants. An increasing content of calcium phosphate (CP) resulted in a decrease of mechanical and chemical stability, while the bioactivity increased in simulated body fluid (SBF). In vitro experiments with human osteoblast cells (HOB) revealed that the cells grew well on all samples but are affected by dissolution behavior of the studied coatings. This work demonstrates the overall good mechanical strength, the excellent interfacial bonding and the bioactivity potential of coatings with higher TZ contents, which provide a highly interesting coating for dental implants.

Characterization of wet powder-sprayed zirconia/calcium phosphate coating for dental implants.

PURPOSE: Yttria-stabilized zirconia (TZ) is used for dental applications because of its low toxicity and beneficial mechanical properties, but it does not stimulate bone regeneration around the implant due to its bioinertness. Therefore, hydroxyapatite (HA) coatings are often utilized to increase the surface bioactivity and to achieve a better osseointegration. These coatings, however, are chemically nonstable and provide a weak bonding to the substrate surface. MATERIALS AND METHODS: In this study, zirconia substrates were coated with a calcium phosphate/zirconia mixture to achieve ceramic coatings with a high bioactivity potential and a good mechanical stability. The coatings were obtained by wet powder spraying (WPS). Pure HA and TZ coatings were employed as reference materials. The coatings were characterized with regard to microstructure, surface roughness, and phase composition. Scratch tests were carried out to investigate the coating adhesion. The influence of the coating on the mechanical strength was evaluated with the ball on three balls test (B3B). In addition, zirconia dental implant screws were also coated and inserted in a biomechanical test block and bovine rip bone. RESULTS: After sintering, the mixed coating exhibited a porous morphology with a surface roughness of about 4 µm and a total porosity of 17%. Phase analysis showed a transformation from TZ and HA to calcium zirconium oxide and tricalcium phosphate. Investigations of the bond strength confirmed a strong adhesion of the mixed coating to the substrate, while the biaxial fracture strength was only slightly affected. Insertion experiments confirmed the scratch test results and evidenced an intact mixed coating on the zirconia screw. CONCLUSIONS: The present study revealed a higher stability and firm adhesion of the mixed coating compared with a pure calcium phosphate coating. We also successfully demonstrate the particular versatility of the WPS technique for dental implants by coating a complex curved surface.

Magnesium-containing mixed coatings on zirconia for dental implants: mechanical characterization and in vitro behavior.

An important challenge in the field of dental and orthopedic implantology is the preparation of implant coatings with bioactive functions that feature a high mechanical stability and at the same time mimic structural and compositional properties of native bone for a better bone ingrowth. This study investigates the influence of magnesium addition to zirconia-calcium phosphate coatings. The mixed coatings were prepared with varying additions of either magnesium oxide or magnesium fluoride to yttria-stabilized zirconia and hydroxyapatite. The coatings were deposited on zirconia discs and screw implants by wet powder spraying. Microstructure studies confirm a porous coating with similar roughness and firm adhesion not hampered by the coating composition. The coating morphology, mechanical flexural strength and calcium dissolution showed a magnesium content-dependent effect. Moreover, the in vitro results obtained with human osteoblasts reveal an improved biological performance caused by the presence of Mg(2+) ions. The magnesium-containing coatings exhibited better cell proliferation and differentiation in comparison to pure zirconia-calcium phosphate coatings. In conclusion, these results demonstrate that magnesium addition increases the bioactivity potential of zirconia-calcium phosphate coatings and is thus a highly suitable candidate for bone implant coatings.

Mechanical evaluation of calcium-zirconium-silicate (baghdadite) obtained by a direct solid-state synthesis route.

Ca3ZrSi2O9 (baghdadite) has become a major research focus within the biomaterial community due to its remarkable in-vitro and in-vivo bioactivity. Although baghdadite seems to exhibit interesting biological properties, as yet there has been no data published concerning its mechanical properties. This lack of knowledge hinders targeting this novel bioactive material towards potential applications. In this study we prepare dense Ca3ZrSi2O9 bulk ceramics for the first time, allowing the evaluation of its mechanical properties including hardness, bending strength, Young׳s modulus, and fracture toughness. The preparation of baghdadite has been accomplished by a direct solid-state synthesis in combination with conventional sintering at 1350-1450°C for 3h. Our results show that samples sintered at 1400°C exhibit the best mechanical properties, resulting in a bending strength, fracture toughness, and hardness of 98±16MPa, 1.3±0.1MPam(0.5), and 7.9±0.2GPa. With a comparable mechanical strength to hydroxyapatite, but with an increased fracture toughness by 30% and hardness by 13% baghdadite is highly suitable for potential applications in non-load bearing areas (e.g. coatings or filler materials).

A novel one-pot process for near-net-shape fabrication of open-porous resorbable hydroxyapatite/protein composites and in vivo assessment.

We present a mild one-pot freeze gelation process for fabricating near-net, complex-shaped hydroxyapatite scaffolds and to directly incorporate active proteins during scaffold processing. In particular, the direct protein incorporation enables a simultaneous adjustment and control of scaffold microstructure, porosity, resorbability and enhancement of initial mechanical and handling stability. Two proteins, serum albumin and lysozyme, are selected and their effect on scaffold stability and microstructure investigated by biaxial strength tests, electron microscopy, and mercury intrusion porosimetry. The resulting hydroxyapatite/protein composites feature adjustable porosities from 50% to 70% and a mechanical strength ranging from 2 to 6 MPa comparable to that of human spongiosa without any sintering step. Scaffold degradation behaviour and protein release are assessed by in vitro studies. A preliminary in vivo assessment of scaffold biocompatibility and resorption behaviour in adult domestic pigs is discussed. After implantation, composites were resorbed up to 50% after only 4 weeks and up to 65% after 8 weeks. In addition, 14% new bone formation after 4 weeks and 37% after 8 weeks were detected. All these investigations demonstrate the outstanding suitability of the one-pot-process to create, in a customisable and reliable way, biocompatible scaffolds with sufficient mechanical strength for handling and surgical insertion, and for potential use as biodegradable bone substitutes and versatile platform for local drug delivery.