Hydroxyapatite Surface Research Articles

MiR-34a-Functionalized Hydroxyapatite by Lyophilization Promoted Bone Regeneration in Irradiated Bone Defects

The rehabilitation of bone defects after radiotherapy requires the development of osteoinductive bone substitutes. MicroRNA could be used as an osteogenic factor to fabricate functional materials for bone regeneration. In this study, we used miR-34a to enhance bone regeneration after irradiation. We lyophilized lipofectamine-agomiR-34a lipoplexes on hydroxyapatite (HA) to develop miR-34a-functionalized hydroxyapatite (HA-agomiR-34a). The morphology was observed by scanning electron microscope and atomic force microscope. Fluorescence microscopy confirmed the retention of agomiR-34a on the surface of HA. HA-agomiR-34a showed high transfection efficiency and good biocompatibility. HA-agomiR-34a enhanced the osteoblastic differentiation of radiation-impaired bone marrow stromal cells (BMSCs). Implantation of HA-agomiR-34a promoted bone regeneration in irradiated bone defects. HA-agomiR-34a may be a novel and safe bone substitute to promote the reconstruction of bone defects after radiotherapy.

A High-Performance Anti-Corrosive Epoxy Coating Based on Ultra-Thin Hydroxyapatite Nanosheets with pH-Responsive Functions.

The changes in the working environment have necessitated greater requirements in terms of the long-term anti-corrosion ability of metal anti-corrosion coatings, and the emergence of intelligent coatings has met this demand. A nanocontainer with a hydrophobic inner cavity and hydrophilic outer cavity called β-cyclodextrin (β-CD) was grafted onto the surface of hydroxyapatite (HAp) with a silane coupling agent, encapsulating benzotriazole (BTA) and embedded in epoxy resin to improve the coating anticorrosion performance. The excellent corrosion resistance of the coating in immersion and scratch experiments was derived from the inert protective layer formed by the reaction of the rapidly released corrosion inhibitor with the corrosion products on the metal surface. After 30 days of immersion experiment, the coating could still maintain the low-frequency impedance value of 6.28 × 107 Ω cm2. In this work, the enhancement of the physical barrier function of HAp nanoparticle and the pH-response function conferred by β-cyclodextrin provided the coating with good passive and active acting abilities in corrosive environments, respectively.

A multifunctional anticorrosive coating of hydroxyapatite platform based on metal-organic framework decoration with pH-responsive behavior

This study aimed to design a composite epoxy coating HZB/EP with pH-responsive behavior by grafting different material functions. In this approach, ZIF-8 particles were self-assembled on the surface of hydroxyapatite (HAp) through in situ growth, followed by encapsulation of the corrosion inhibitor BTA. Scanning electron microscopy (SEM) analysis of the coating section revealed a significant improvement in the dispersion of HZB in the resin compared to hydroxyapatite (HAp), resulting in a notable reduction in coating defects upon the addition of HZB. Electrochemical impedance spectroscopy (EIS) tests demonstrated that HZB/EP maintained a high low-frequency impedance value even after immersion in a 3.5% NaCl solution for 40 days, exhibiting an impedance magnitude 4–5 orders of magnitude higher than Pure EP. Additionally, scratch and salt spray tests validated the release and action process of the corrosion inhibitor BTA. This study presents a novel strategy for the development of multifunctional anticorrosive coatings.

Structural and biological evaluation of novel vanadium/Yttrium co-doped hydroxyapatite for bone tissue engineering applications

Hydroxyapatite (HA) is widely used in various medical fields due to its exceptional bioactivity, bio-affinity, and biocompatibility. However, the potential of biomaterials co-doped with metal ions for specific biomedical applications remains underexplored. In this study, we modified the HA structure by introducing vanadium (V) and yttrium (Y) to enhance its physicochemical and biological properties. V-Y co-doped HA (V-Y:HA) samples were prepared by the wet precipitation method using a reflux condensation setup with three different concentrations (0.005 M, 0.01 M, and 0.02 M) of V and Y. The addition of V and Y significantly influenced the biochemical properties and crystal structure of HA. X-ray diffraction (XRD) analysis revealed a modified crystal structure and the presence of the β-tricalcium phosphate (β -TCP) phase in the sample with a higher V concentration. V and Y incorporation resulted in smaller crystallite sizes and noticeable changes in lattice parameters. Scanning electron microscopy (SEM) images displayed sphere-like morphology with extensive aggregation. Fourier-transform infrared spectroscopy (FT-IR) and Raman analysis confirmed the presence of functional groups and phosphate vibrational modes in V-Y:HA samples. X-ray photoelectron spectroscopy (XPS) revealed the ionic and oxide forms of vanadium and the electronic states of yttrium. The as-prepared samples exhibited excellent mechanical strength, reduced porosity, and improved hemocompatibility compared to pure HA. The V-Y:HA sample with a higher V concentration demonstrated enhanced antibacterial activity against P. aeruginosa and S. aureus. In-vitro bioactivity assessment after 21 days revealed enhanced apatite formation on the surface of HA and V-Y:HA materials. These findings suggest that the novel V-Y:HA nanomaterials have great potential as biomaterials for bone tissue engineering and related applications.

Electrostatic and Covalent Binding of an Antibacterial Polymer to Hydroxyapatite for Protection against Escherichia coli Colonization.

Orthopedic-device-related infections are notorious for causing physical and psychological trauma to patients suffering from them. Traditional methods of treating these infections have relied heavily on antibiotics and are becoming ineffectual due to the rise of antibiotic-resistant bacteria. Mimics of antimicrobial peptides have emerged as exciting alternatives due to their favorable antibacterial properties and lack of propensity for generating resistant bacteria. In this study, the efficacy of an antibacterial polymer as a coating material for hydroxyapatite and glass surfaces, two materials with wide ranging application in orthopedics and the biomedical sciences, is demonstrated. Both physical and covalent modes of attachment of the polymer to these materials were explored. Polymer attachment to the material surfaces was confirmed via X-ray photoelectron spectroscopy and contact angle measurements. The modified surfaces exhibited significant antibacterial activity against the Gram-negative bacterium E. coli, and the activity was retained for a prolonged period on the surfaces of the covalently modified materials.

Gene expression during the development of Mycobacterium smegmatis biofilms on hydroxyapatite surfaces.

Bacterial biofilms are a consortium of bacteria that are strongly bound to each other and the surface on which they developed irreversibly. Bacteria can survive adverse environmental conditions and undergo changes when transitioning from a planktonic form to community cells. The process of mycobacteria adhesion is complex, involving characteristics and properties of bacteria, surfaces, and environmental factors; therefore, the formation of different biofilms is possible. Cell wall-, lipid-, and lipid transporter-related genes (glycopeptidolipids, GroEL1, protein kinase) are important in mycobacterial biofilm development. We investigated gene expression during in vitro development of Mycobacterium smegmatis biofilms on a hydroxyapatite (HAP) surface. Biofilm formation by M. smegmatis cells was induced for 1, 2, 3, and 5days on the HAP surface. Mycobacteria on polystyrene generated an air-liquid interface biofilm, and on the fifth day, it increased by 35% in the presence of HAP. Six genes with key roles in biofilm formation were analyzed by real-time RT‒qPCR during the biofilm formation of M. smegmatis on both abiotic surfaces. The expression of groEL1, lsr2, mmpL11, mps, pknF, and rpoZ genes during biofilm formation on the HAP surface did not exhibit significant changes compared to the polystyrene surface. These genes involved in biofilm formation are not affected by HAP.

Improving interface interactions in PLA/HAP composites with hydroxyapatite surface modification

ABSTRACT PLA/HAP composites have attracted significant attention in material science, especially in the field of biomaterials. However, these composites have suffered from unfavorable interface interactions between PLA and HAP interfaces, which limits the applications . In this study, we aimed to improve the interface interactions of PLA/HAP composite by modifying the HAP surface. For this purpose, HAP particles were functionalized with three different silane modifying agents, including (3-Aminopropyl)trimethoxysilane (AMMO), (3-glycidyloxypropyl)trimethoxysilane (GLYMO) and (3-triethoxysilyl)propylsuccinic anhydride (GF-20). The obtained modified HAP (m-HAP) were used to prepare PLA/m-HAP. Interface interactions of composites were characterized by Fourier transform infrared spectrophotometer (FT-IR) and differential scanning calorimetry (DSC). In addition, Vickers hardness tests were performed to reveal the effect of silane modifying agents on hardness before and after the in vitro degradation test.

Effects of fluoride on in vitro hydroxyapatite demineralisation analysed by 19F MAS-NMR

IntroductionFluoride plays a major role in inhibiting enamel dissolution and promoting fluorapatite formation. Porous hydroxyapatite (HAP) discs can be used as an enamel analogue in artificial demineralisation/remineralisation studies.MethodThe aim of the study was to monitor the fluoride-mineral phases formed on HAP surfaces as a function of fluoride concentration ([F−]) under demineralising conditions, using 19F magic angle spinning nuclear magnetic resonance (MAS-NMR) spectroscopy, and compare the results with a previous study using an enamel substrate. Porous HAP blocks were immersed in demineralisation solutions (0.1 M acetic acid, pH 4.0) with increasing [F−] (0–1450 ppm).ResultsAt below 50 ppm [F−], 19F MAS-NMR showed fluoride-substituted apatite formation; above 50 ppm [F−], calcium fluoride (CaF2) was formed in increasing proportions. These results mirrored those of previous similar studies with an enamel substrate. Further increases in fluoride caused no further measurable reduction in demineralisation but increased the proportion of CaF2 formed. The total calcium concentration [Ca] and total phosphorus [P] concentrations in the solution were measured by inductively coupled plasma atomic emission spectroscopy. At high fluoride concentrations, the solution total [P] increased, and the molar Ca:P ratios decreased to values consistent with the formation of CaF2. However, Ca:P ratios found at low [F−] were higher than those in the previous enamel study and consistent with the formation of a partially fluoridated apatite.ConclusionsUnder demineralising conditions, CaF2 formed on HAP at an [F−] of 50 ppm and above, whereas fluoridated apatite formed at an [F−] below 50 ppm. The results were consistent with those obtained when an enamel substrate was used.

Resolving protein-mineral interfacial interactions during in vitro mineralization by atom probe tomography

Organic macromolecules exert remarkable control over the nucleation and growth of inorganic crystallites during (bio)mineralization, as exemplified during enamel formation where the protein amelogenin regulates the formation of hydroxyapatite (HAP). However, it is poorly understood how fundamental processes at the organic-inorganic interface, such as protein adsorption and/or incorporation into minerals, regulates nucleation and crystal growth due to technical challenges in observing and characterizing mineral-bound organics at high-resolution. Here, atom probe tomography techniques were developed and applied to characterize amelogenin-mineralized HAP particles in vitro, revealing distinct organic-inorganic interfacial structures and processes at the nanoscale. Specifically, visualization of amelogenin across the mineralized particulate demonstrates protein can become entrapped during HAP crystal aggregation and fusion. Identification of protein signatures and structural interpretations were further supported by standards analyses, i.e., defined HAP surfaces with and without amelogenin adsorbed. These findings represent a significant advance in the characterization of interfacial structures and, more so, interpretation of fundamental organic-inorganic processes and mechanisms influencing crystal growth. Ultimately, this approach can be broadly applied to inform how potentially unique and diverse organic-inorganic interactions at different stages regulates the growth and evolution of various biominerals.

Adsorption and X-ray photoelectron spectroscopy investigation of bisphosphonates on titania and hydroxyapatite surfaces

This study investigates the adsorption of bisphosphonates (BPs) on TiO2, hydroxyapatite (HA), and TiO2+HA composite surfaces. We first examined the adsorption of these molecules on titania particles and explored the influence of UV irradiation through adsorption curves. Our findings indicate that surface irradiation leads to an increase in the adsorbed BP content due to enhanced BP deprotonation and hydroxyl group generation. Additionally, we evaluated the adsorption of BPs on the TiO2, HA, and TiO2+HA surfaces primarily through X-ray photoelectron spectroscopy (XPS). Our results suggest that BPs adsorb onto TiO2 via a condensation reaction between the BPs and titania surfaces, while phosphate and Ca2+ ions coordinate onto HA surfaces. All functionalized films exhibit a water contact angle of zero. Atomic force microscopy (AFM) measurements show that BP adsorption had less impact on titania topography than HA topography, and mixed films demonstrated behavior similar to that of titania films.

Targeting tumor energy metabolism via simultaneous inhibition of mitochondrial respiration and glycolysis using biodegradable hydroxyapatite nanorods

Tumor cells obtain energy supply from the unique metabolic pathways of mitochondrial respiration and glycolysis, which can be used interchangeably to produce adenosine triphosphate (ATP) for survival. To simultaneously block the two metabolic pathways and sharply cut off ATP supply, a multifunctional “nanoenabled energy interrupter” (called as HNHA-GC) was prepared by attaching glucose oxidase (GOx), hyaluronic acid (HA), and 10-hydroxycamptothecin (CPT) on the surface of degradable hydroxyapatite (NHA) nanorods. After targeted delivery of HNHA-GC to the tumor site by HA, the tumor-selective acid degradation of HNHA-GC as well as the subsequent deliveries of Ca2+, drug CPT, and GOx take place. The released Ca2+ and CPT induce mitochondrial dysfunction by Ca2+ overload and chemotherapy respectively, while the GOx-triggered glucose oxidation inhibits glycolysis by starvation therapy (exogenous effect). The generated H2O2 and released CPT increase the intracellular reactive oxygen (ROS) level. Moreover, the generated H+ and enhanced ROS promote Ca2+ overload by accelerating the degradation of HNHA-GC and preventing intracellular Ca2+ efflux, respectively (endogenous effect). As a result, the HNHA-GC displays a promising therapeutic modality for simultaneously cutting off mitochondrial and glycolytic ATP production through a combination of Ca2+ overload, chemotherapy, and starvation therapy.

Co-doped hydroxyapatite as photothermal catalyst for selective CO2 hydrogenation

The rational design and in deep understanding of efficient, affordable and stable materials to promote the light-assisted production of fuels and commodity chemicals is very appealing for energy crisis and climate change amelioration. Herein, we have prepared a series of Co-doped hydroxyapatite (HAP) catalysts with different Co content. The materials structure has been widely investigated by XRD, FT-IR, HRTEM, XPS, XAS, as well as computational simulations based on Density Functional Theory (DFT) with PBE functional. At low Co loading, there is a partial substitution of Ca cations in the HAP structure, while higher loadings promote the precipitation of small (∼ 2 nm) Co nanoparticles on the HAP surface. For the optimal Co content, a constant CO rate of 62 mmol·g−1·h−1 at 1 sun illumination and 400 °C, with the material being stable for 90 h. Visible and NIR photons have been determined responsible of the light-assisted activity enhanced. Mechanistic studies based on both experimental and DFT simulations show that H2 preferentially adsorbs to metallic Co, while CO2 adsorbs to the HAP surface oxygen. Moreover, both direct photo- and plasmon-driven contributions have been separated in order to study their mechanisms independently.

Tailoring of Ag3PO4-Anchored Hydroxyapatite Nanophotocatalyst with Tunable Particle Size by a Facile Ion-Exchange Method for Organic Textile Dyes Photodegradation

Silver phosphate (Ag3PO4) exhibits excellent photocatalytic performance but has limitation in its stability and reusability. To overcome the issue of reusability, composites of silver phosphate nanostructures are tailored. This paper elucidates the photocatalytic study of silver phosphate-anchored hydroxyapatite (HA) (Ca10(PO4)6(OH)2) on the degradation of commercial textile dye, Sunfix Red (SR) S3B 150% by changing the experimental parameters such as catalyst concentration, dye concentration, and pH of the dye solution under the sunlight. Silver phosphate-anchored HA (HA_Ag3PO4(x)) was prepared via a two-step process. HA was synthesized by a simple wet chemical precipitation and silver phosphate-anchored HA (HA_Ag3PO4(x)) via in situ ion-exchange method. The synthesized photocatalysts were subjected to characterization studies such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), ultraviolet–visible spectroscopy, and X-ray photoelectron spectroscopy (XPS). All the synthesized composites exhibited the bandgap of 2.34 eV and degraded SR in 45 min with the rate constant 0.07168 min−1 under sunlight. The trapping tests for radicals were done to study the role of free radicals in the degradation of the dye, SR, and the possible degradation mechanism was proposed. The postphotocatalytic analysis of XRD showed that the structure of Ag3PO4 remained intact declaring its structural stability. It was observed that the concentration of AgNO3 precursor influenced the number of nucleation over the surface of HA and the particle size of Ag3PO4. The applicability of the synthesized material was extended to other organic dyes such as Sunzol Black (SB) DN conc., methylene blue (MB), and rhodamine B (RhB) by the prepared composite and the findings were presented.

Beneficial effect of in-situ citrate-grafting of hydroxyapatite surface for water treatment

Hybrid materials based on hydroxyapatite (HAP) were synthesized by the co-precipitation method in the presence of citric acid (Cit) at different molar ratios Cit/HAP (wCit-HAP). By increasing the quantity of citric acid added, a loss of crystallinity of the grafted materials is observed and this grafting makes it possible to control the size of their nanoparticles and the surface characteristics. Their surface properties were tested by adsorption of methylene blue (MB) as a model dye. Several parameters influencing pollutant removal from aqueous solutions are discussed. The contact time to reach equilibrium for maximum adsorption does not exceed 60 min and the kinetic data are well fitted by a pseudo second order model. The best adsorption capacity was obtained for 0.2Cit-HAP. The calculated thermodynamic parameters showed that the adsorption was a spontaneous and endothermic process and that all ΔH° values are below 20 kJ mol−1. This indicates that there are weak electrostatic Van der Waals forces as well as the formation of hydrogen bonds. This approach was proven by quantum chemical calculations performed using the density function theory (DFT) method which provided new insights into the mechanism of adsorption.

A Tunable Calcium Phosphate Coating to Drive in vivo Osseointegration of Composite Engineered Tissues

Varying degrees of hydroxyapatite (HA) surface functionalization have been implicated as the primary driver of differential osteogenesis observed in infiltrating cells. The ability to reliably create spatially controlled areas of mineralization in composite engineered tissues is of growing interest in the field, and the use of HA-functionalized biomaterials may provide a robust solution to this challenge. In this study, we successfully fabricated polycaprolactone salt-leached scaffolds with two levels of a biomimetic calcium phosphate coating to examine their effects on MSC osteogenesis. Longer duration coating in simulated body fluid (SBF) led to increased HA crystal nucleation within scaffold interiors as well as more robust HA crystal formation on scaffold surfaces. Ultimately, the increased surface stiffness of scaffolds coated in SBF for 7 days in comparison to scaffolds coated in SBF for 1 day led to more robust osteogenesis of MSCs in vitro without the assistance of osteogenic signaling molecules. This study also demonstrated that the use of SBF-based HA coatings can promote higher levels of osteogenesis in vivo. Finally, when incorporated as the endplate region of a larger tissue-engineered intervertebral disc replacement, HA coating did not induce mineralization in or promote cell migration out of neighboring biomaterials. Overall, these results verified tunable biomimetic HA coatings as a promising biomaterial modification to promote discrete regions of mineralization within composite engineered tissues.

Theoretical Investigations on the Interactions of Urea with Hydroxyl and Non-Hydroxyl Hydroxyapatite Surface

We performed an investigation on urea interacting with hydroxyapatite (HA). The oxygen atoms on HA are either left alone or added with hydrogen to create hydroxyl to resemble the HA surface. Using B3LYP and 3 different basis sets, it was found that urea was able to interact positively with either hydroxyl or non-hydroxyl surface of HA. The Gaussian 09 and Multiwfn software were employed to conduct the calculations. The most favorable interaction has interaction energy of –1.36 eV, which was obtained with the 2 largest basis sets considered, on the pure hydroxyl surface. From the topology analysis on electron density and the non-covalent interaction analysis, it was found that the main attractions between urea and HA were due to the carbonyl oxygen and hydrogen of urea, and hydrogen, oxygen, and calcium on the HA surface. The bond length of newly bonded atoms ranges from 1.62 to 5.18 Å, whereas the energy gap has range between 0.46 to 1.14 eV. All the analysis performed in this study agreed with the results obtained in the formation of favorable interactions and complement previous experimental results that HA can bond with urea molecule. HIGHLIGHTS First known attempt to compare hydrogen-terminated and non-terminated surface of HA in urea adsorption The atoms involved in the adsorption were identified, and electronic structure of the possible combination was analysed and studied using topology and non-covalent interaction analysis Urea attached to both surfaces are stable, with negative interaction energy, confirming experiments’ results that urea can be adsorbed to HA GRAPHICAL ABSTRACT

Molecular dynamics exploration of ion association mechanism of apatite controlled by a nanogrooved hydroxyapatite surface

Surface topography modification is a promising tissue engineering technology that provides an adjustable geometric microenvironment for the implant-tissue interface. Nanogrooves can affect the amount and arrangement of apatite deposition, which plays a crucial role in the formation of bionic bone tissue in the preferred direction. The effects of grooved topography on the ion association must be understood for designing and optimizing bone implant materials. We performed molecular dynamics and metadynamics simulations to explore the effect of grooves with different slope angles on the ion association of Ca2+ and PO43- ions. The ion deposition degree could be controlled by regulating the slope angle of the nanogrooves. The groove model with a 60° slope angle has the greatest biological activity for ion deposition. Ions were selectively adsorbed at the sharp corners of the groove. This phenomenon was attributed to relative differences in binding thermostability in different regions of the groove, which could partially explain why a grooved topography can improve the production of a well-organized apatite structure. Our results provide a molecular mechanism to understand the effects of the grooved topography on the ion association, which can aid in optimizing the biological activity of materials through topography-modified tissue engineering technology.

Investigation into the Photochemical Properties of Methylene Blue-Immobilized Hydroxyapatite Nanoparticles for Theranostic Application

In the biomedical field, there has been a requirement for developing theranostic nanomaterials with higher biosafety, leading to both diagnosis and therapy. Methylene blue (MB+) is an organic dye with both photoluminescence (PL) and photosensitization abilities to generate singlet oxygen (1O2). However, MB+ easily loses its generation ability by hydrogen reduction in vivo or by forming aggregates. In this study, MB+ immobilized on biocompatible hydroxyapatite (HA) nanoparticles was applied for the bifunctions of efficient PL and photosensitization. The MB+-immobilized HA nanoparticles (MH) formed aggregates with sizes of 80-100 nm in phosphate buffer (PB). The generation amount and efficiency of 1O2 from the nanoparticles in PB seem to depend on the immobilized MB+ amount and the percentage of the monomer, respectively. Considering the larger immobilized amount and percentage of the MB+ monomer, it was found that there was MH with the lower generation amount and efficiency of 1O2 to exhibit the highest PL intensity. The photofunctional measurement of MB+ revealed the state of MB+ molecules on the HA surface, and it was suggested that the MB+ molecules immobilized on the MH surface would form more hydrogen bonds to change their excitation states. In the cellular experiments, the Hela cancer cells reacted with the nanoparticles and showed red-color PL, indicating cellular imaging. Furthermore, the adherent cell coverage decreased by 1O2 generation, indicating the importance of the immobilization amount of the MB+ monomer. Therefore, theranostic nanomaterials with biosafety were successfully synthesized to show two photofunctions, which provide both cellular imaging and photodynamic therapy by the nanohybrid system between HA and MB+.

Enhanced water defluoridation using ion channel modified hydroxyapatite: Experimental, mechanisms and DFT calculation

Hydroxyapatite (HAP) is one of the fluoride adsorbents to remove fluoride in water, but F- is hard to enter the lattice of HAP caused by spatial confinement and competitive adsorption, which leads to low defluoridation efficiency. In this study, Ca-deficient regulation method was used to create ion channels during HAP synthesis to overcome the inhibition caused by spatial confinement effect, which increased the defluoridation capacity by 50 % from 1.56 to 2.34 mg/g (Initial F- concentration: 5 mg/L). The effects of dosage, pH, initial F- concentration and co-existing ions on defluoridation process were evaluated and the dosage of 1.4 g/L under neutral condition was the economic condition. The adsorption performance followed the Pseudo-second-order kinetic model and Freundlich isotherm model, which was a spontaneous and endothermic process. The results of molecular mechanics and density functional theory (DFT) calculations showed ion channels near the F- adsorption sites on HAP surface were generated due to the calcium deficiency, which effectively promoted F- into the lattice. The defects also changed the adsorption energy and sites of HF and F-, which reduced the competitive adsorption. In addition, the catalytic decomposition of HF molecules occurred on the surface of HAP was discovered for the first time.

Analytical investigation of nano-bio interfacial protein mediation for fibroblast adhesion on hydroxyapatite nanoparticles.

A quartz crystal microbalance with dissipation (QCM-D) analysis was used to investigate fetal bovine serum (FBS) protein preadsorption on a hydroxyapatite (HAp) surface and the subsequent adhesion process of fibroblasts as compared with the case of oxidized poly(styrene) (PSox). The results showed that the preadsorption of FBS proteins on HAp promoted the subsequent initial cell adhesion ability. Moreover, the measured frequency (Δf) and dissipation shift (ΔD) curves, ΔD-Δf plots and viscoelastic analysis were used to study the initial cell adhesion process in real time. It was suggested that FBS-HAp showed sensitive changes in mass and viscoelasticity as compared with FBS-PSox, which realized the in situ reflection of the cell adhesion state, and the interfacial reactions between the cells and FBS-HAp surfaces such as dehydration and binding occurred to promote the initial cell adhesion and spreading. The viscoelastic analysis of the interface layer showed that the adhered cells on FBS-HAp could secrete some viscous substances such as extracellular matrix (ECM) proteins at the interfaces to provide good adhesion behaviors, and the Voigt-based viscoelastic model could clearly reveal the cellular interfacial viscoelasticity depending on the substrate surface. In addition, the morphology of cells was observed by confocal laser scanning microscopy (CLSM) and atomic force microscopy (AFM), and it was found that the pseudopodia were more uniformly stretched on FBS-HAp than on FBS-PSox. Furthermore, the state of the interfacial protein layer was analyzed by localized Fourier-transform infrared (FT-IR) spectroscopy and fluorescence microscopy (FLM), and it was indicated that the type of substrate affects the formation state of ECM proteins, resulting in changes in cell adhesion properties and morphology. The abundant formation of connective proteins (i.e., collagen type I) on FBS-HAp promoted subsequent pseudopodia formation and cell spreading. Therefore, the initial adhesion properties of fibroblasts on the FBS-HAp surface were systematically studied, which is of great importance for understanding the interfacial interaction between biomaterials and cells, and has great application value in biomedical fields.