Near-Infrared Light-Responsive Size-Selective Lateral Flow Chip for Single-Cell Manipulation of Circulating Tumor Cells.

Accurately obtaining information on the heterogeneity of CTCs at the single-cell level is a very challenging task that may facilitate cancer pathogenesis research and personalized therapy. However, commonly used multicellular population capture and release assays tend to lose effective information on heterogeneity and cannot accurately assess molecular-level studies and drug resistance assessment of CTCs in different stages of tumor metastasis. Herein, we designed a near-infrared (NIR) light-responsive microfluidic chip for biocompatible single-cell manipulation and study the heterogeneity of CTCs by a combination of the lateral flow microarray (LFM) chip and photothermal response system. First, immunomagnetic labeling and a gradient magnetic field were combined to distribute CTCs in different regions of the chip according to the content of surface markers. Subsequently, the LFM chip achieves high single-cell capture efficiency and purity (even as low as 5 CTCs per milliliter of blood) under the influence of lateral fluid and magnetic fields. Due to the rapid dissolution of the gelatin capture structure at 37 °C and the photothermal properties of gold nanorods, the captured single CTC cell can be recovered in large quantities at physiological temperature or released individually at a specific point by NIR. The multifunctional NIR-responsive LFM chip demonstrates excellent performance in capture and site release of CTCs with high viability, which provides a robust and versatile means for CTCs heterogeneity study at the single-cell level.

Synergetic integrations of bone marrow stem cells and transforming growth factor-ß1 loaded chitosan nanoparticles blended silk fibroin injectable hydrogel to enhance repair and regeneration potential in articular cartilage tissue.

The cartilage repair and regeneration show inadequate self-healing capability and have some complications, which are inordinate challenges in clinical therapy. Biopolymeric injectable hydrogels, a prominent type of cell-carrier as well tissue engineering scaffolding materials, establish promising therapeutic potential of stem cell-based cartilage-regeneration treatment. In addition, injectable scaffolding biomaterial should have rapid gelation properties with adequate rheological and mechanical properties. In the present investigation, we developed and fabricated the macromolecular silk fibroin blended with polylysine modified chitosan polymer (SF/PCS) using thermal-sensitive glycerophosphate (GP), which contains effective gelation ability, morphology, porosity and also has enhanced mechanical properties to induce physical applicability, cell proliferation and nutrient exchange in the cell-based treatment. The developed and optimised injectable hydrogel group has good biocompatibility with human fibroblast (L929) cells and bone marrow-derived mesenchymal stem cells (BMSCs). Additionally, it was found that SF/PCS hydrogel group could sustainably release TGF-ß1 and efficiently regulate cartilage-specific and inflammatory-related gene expressions. Finally, the cartilage-regeneration potential of the hydrogel groups embedded with and without BMSCs were evaluated in SD rat models under histopathological analysis, which showed promising cartilage repair. Overall, we conclude that the TGF-ß1-SF/PCS injectable hydrogel demonstrates enhanced in vitro and in vivo tissue regeneration properties, which lead to efficacious therapeutic potential in cartilage regeneration.

Determination of DNA and RNA Methylation in Circulating Tumor Cells by Mass Spectrometry.

DNA methylation (5-methylcytosine, 5-mC) is the best characterized epigenetic mark that has regulatory roles in diverse biological processes. Recent investigation of RNA modifications also raises the possible functions of RNA adenine and cytosine methylations on gene regulation in the form of "RNA epigenetics." Previous studies demonstrated global DNA hypomethylation in tumor tissues compared to healthy controls. However, DNA and RNA methylation in circulating tumor cells (CTCs) that are derived from tumors are still a mystery due to the lack of proper analytical methods. In this respect, here we established an effective CTCs capture system conjugated with a combined strategy of sample preparation for the captured CTCs lysis, nucleic acids digestion, and nucleosides extraction in one tube. The resulting nucleosides were then further analyzed by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). With the developed method, we are able to detect DNA and RNA methylation (5-methyl-2'-deoxycytidine, 5-methylcytidine, and N(6)-methyladenosine) in a single cell. We then further successfully determined DNA and RNA methylation in CTCs from lung cancer patients. Our results demonstrated, for the first time, a significant decrease of DNA methylation (5-methyl-2'-deoxycytidine) and increase of RNA adenine and cytosine methylations (N(6)-methyladenosine and 5-methylcytidine) in CTCs compared with whole blood cells. The discovery of DNA hypomethylation and RNA hypermethylation in CTCs in the current study together with previous reports of global DNA hypomethylation in tumor tissues suggest that nucleic acid modifications play important roles in the formation and development of cancer cells. This work constitutes the first step for the investigation of DNA and RNA methylation in CTCs, which may facilitate uncovering the metastasis mechanism of cancers in the future.

High-Efficiency Capture of Individual and Cluster of Circulating Tumor Cells by a Microchip Embedded with Three-Dimensional Poly(dimethylsiloxane) Scaffold.

Effective isolation of circulating tumor cells (CTCs) has great significance for cancer research but is highly challenged. Here, we developed a microchip embedded with a three-dimensional (3D) PDMS scaffold by a quadratic-sacrificing template method for high-efficiency capture of CTCs. The microchip was gifted with a 3D interconnected macroporous structure, strong toughness, and excellent flexibility and transparency, enabling fast isolation and convenient observation of CTCs. Especially, 3D scaffold chip perfectly integrates the two main strategies currently used for enhancement of cell capture efficiency. Spatially distributed 3D scaffold compels cells undergoing chaotic or vortex migration in the channel, and the spatially distributed nanorough skeleton offers ample binding sites, which synergistically and significantly improve CTCs capture efficiency. Our results showed that 1-118 CTCs/mL were identified from 14 cancer patients' blood and 5 out of these cancer patients showed 1-14 CTC clusters/mL. This work demonstrates for the first time the development of microchip with transparent interconnected 3D scaffold for isolation of CTCs and CTC clusters, which may promote in-depth analysis of CTCs.

A Rationally Designed Upconversion Nanoprobe for in Vivo Detection of Hydroxyl Radical.

The detection of •OH in live organisms is crucial to the understanding of its physiological and pathological roles; while this is too challenging because of the extremely low concentration and high reactivity of the species in the body. Herein, we report the rational design and fabrication of an NIR-light excited luminescence resonance energy transfer-based nanoprobe, which for the first time realizes the in vivo detection of •OH. The nanoprobe is composed of two moieties: upconversion nanoparticles with sandwich structure and bared surface as the energy donor; and mOG, a modified azo dye with tunable light absorption, as both the energy acceptor and the •OH recognizing ligand. The as-constructed nanoprobe exhibited ultrahigh sensitivity (with the quantification limit down to 1.2 femtomolar, several orders of magnitude lower than that of most previous •OH probes), good biocompatibility, and specificity. It was successfully used for monitoring [•OH] levels in live cells and tissues.

Construction of LRET-based nanoprobe using upconversion nanoparticles with confined emitters and bared surface as luminophore.

Upconversion nanoparticles (UCNPs) are promising energy donors for luminescence resonance energy transfer (LRET) and have widely been used to construct nanoprobes. To improve the LRET efficiency, which is currently a limiting factor for UCNPs-based bioassay, we herein propose a strategy to construct LRET-based nanoprobe using UCNPs with confined emitters and bared surface as the luminophore, with Ca(2+) as the proof-of-concept target. The sandwich-structure upconversion nanoparticles (SWUCNPs) are designed with a core-inner shell-outer shell architecture, in which the emitting ions (Ln(3+)) are precisely located in the inner shell near the particle surface, which is close enough to external energy acceptors. The target receptor (Fluo-4) is directly tagged on bared surface of SWUCNPs, which further reduces the donor-to-acceptor distance. Our strategy contributes to significantly improved LRET efficiency and hence affords an ultrahigh sensitivity for Ca(2+) detection. The as-constructed nanoprobe is structurally stable and exhibits good biocompatibility, which ensures uptake and reliable observation in living cells. The nanoprobe can be used for monitoring the different levels of cytosol [Ca(2+)] in living cells. Furthermore, it is applicable in Ca(2+) imaging in mice liver tissues.

Real-time monitoring of H2O2 release from single cells using nanoporous gold microelectrodes decorated with platinum nanoparticles.

Here, we report a self-supported nanoporous gold microelectrode decorated with well-dispersed and tiny platinum nanoparticles as an electrochemical nonenzymatic hydrogen peroxide biosensor. Nanoporous gold was fabricated by electrochemical alloying/dealloying and then small-sized platinum nanoparticles were electrodeposited uniformly on them. This novel hybrid nanostructure endows the sensor with high sensitivity and selectivity towards the reduction of hydrogen peroxide with a low detection limit of 0.3 nM. The sensor has been successfully applied for the measurement of H2O2 release from a single isolated human breast cancer cell, demonstrating its great potential for further physiological and pathological applications.

Inhibition of LncRNA SNHG14 protects chondrocyte from injury in osteoarthritis via sponging miR-137.

Long-chain noncoding small nucleolar RNA host gene 14 (LncRNA SNHG14) is highly expressed in various diseases and promotes diseases progression, but the role and mechanism of LncRNA SNHG14 on targeting miR-137 in promoting osteoarthritis (OA) chondrocyte injury remains unclear. To measure the expression of the LncRNAs SNHG14 and miR-137, cell survival, inflammatory response, chondrocyte apoptosis, and extracellular matrix (ECM) levels, we subjected human chondrocytes to a variety of lipopolysaccharide (LPS) concentrations. To measure the luciferase activity of SNHG14-WT and SNHG14-MUT transfected with miR-137 mimic or miR-NC mimic, luciferase reporter genes were utilized. The results showed that chondrocyte viability was significantly inhibited with LPS treatment and chondrocyte inflammatory response, apoptosis and extracellular matrix degradation were significantly increased. However, the above results were significantly reversed after LncRNA SNHG14 inhibition. The luciferase activity bound to miR-137 was decreased in SNHG14-WT group, but there was no change in SNHG14-mut group, which indicated that LncRNA SNHG14 inhibited miR-137 expression as a miRNA sponge. In conclusion, inhibition of LncRNA SNHG14 attenuates chondrocyte inflammatory response, apoptosis and extracellular matrix degradation by targeting miR-137 in LPS induced chondrocytes.

Microfluidic one-step synthesis of a metal-organic framework for osteoarthritis therapeutic microRNAs delivery.

As a class of short non-coding ribonucleic acids (RNAs), microRNAs (miRNA) regulate gene expression in human cells and are expected to be nucleic acid drugs to regulate and treat a variety of biological processes and diseases. However, the issues with potential materials toxicity, quantity production, poor cellular uptake, and endosomal entrapment limit their further applications in clinical practice. Herein, ZIF-8, a metal-organic framework with noncytotoxic zinc (II) as the metal coordination center, was selected as miRNA delivery vector was used to prepare miR-200c-3p@ZIF-8 in one step by Y-shape microfluidic chip to achieve intracellular release with low toxicity, batch size, and efficient cellular uptake. The obtained miR-200c-3p@ZIF-8 was identified by TEM, particle size analysis, XRD, XPS, and zeta potential. Compared with the traditional hydrothermal method, the encapsulation efficiency of miR-200c-3p@ZIF-8 prepared by the microfluidic method is higher, and the particle size is more uniform and controllable. The experimental results in cellular level verified that the ZIF-8 vectors with low cytotoxicity and high miRNAs loading efficiency could significantly improve cellular uptake and endosomal escape of miRNAs, providing a robust and general strategy for nucleic acid drug delivery. As a model, the prepared miR-200c-3p@ZIF-8 is confirmed to be effective in osteoarthritis treatment.

Antifungal activity of designed α-helical antimicrobial peptides.

Antimicrobial resistance (AMR) has become a major global health concern prompting the quest for new antibiotics with higher efficiency and less proneness to drug resistance. Antimicrobial peptides (AMPs) offer such properties and have therefore gained increasing attention as a new generation of antibiotics to overcome AMR. In an attempt to develop new highly selective and highly efficient antifungal peptides, a sequence (named At1) originating from the natural AMP Ponericin-W1 was used as a lead sequence for rational design of a series of short cationic antifungal peptides named At2-At12. The charge, hydrophobicity, and terminal amino acids of the peptides were modified in a systematic way to investigate the effect of such structural changes on the biological activity of the peptides. Among all the designed peptides, three peptides (coded as At3, At5 and At10) exhibited high antifungal activity without any significant hemolytic activity in human red blood cells. The higher selectivity of these peptides for fungal cells over human cells was further confirmed in cocultures of Candida albicans and human foreskin fibroblasts. These three peptides lacked any hydrophilic residues in their hydrophobic domain, contained lysine residues in their hydrophilic region and had an overall charge of 7+. They also had a higher helical content in microbial membrane mimicking DPPG SUVs than the rest of the peptides. The fungi did not develop any resistance to the designed antifungal peptides even after 25 generations indicating low AMR. At5 was also used in vivo for the treatment of wounds infected with Candida albicans in mice and showed superiority over fluconazole for treating infection and accelerating wound healing. There was an interplay between the hydrophobicity and positive charge density to determine the antifungal activity of the peptides. The results from this study suggest this class of antifungal peptides as promising candidates for antifungal drugs with high efficiency, high biocompatibility and low propensity for drug resistance.

Novel microfluidic swirl mixers for scalable formulation of curcumin loaded liposomes for cancer therapy.

Liposomes have been widely used in nanomedicine for the delivery of hydrophobic and hydrophilic anticancer agents. The most common applications of these formulations are vaccines and anticancer formulations (e.g., mRNA, small molecule drugs). However, large-scale production with precise control of size and size distribution of the lipid-based drug delivery systems (DDSs) is one of the major challenges in the pharmaceutical industry. In this study, we used newly designed microfluidic swirl mixers with simple 3D mixing chamber structures to prepare liposomes at a larger scale (up to 320 mL/min or 20 L/h) than the commercially available devices. This design demonstrated high productivity and better control of liposome size and polydispersity index (PDI) than conventional liposome preparation methods. The microfluidic swirl mixer devices were used to produce curcumin-loaded liposomes under different processing conditions which were later characterized and studied in vitro to evaluate their efficiency as DDSs. The obtained results demonstrated that the liposomes can effectively deliver curcumin into cancer cells. Therefore, the microfluidic swirl mixers are promising devices for reproducible and scalable manufacturing of DDSs.

Highly selective performance of rationally designed antimicrobial peptides based on ponericin-W1.

Antimicrobial peptides (AMPs) or host-defence peptides act by penetrating and disrupting the bacterial membranes and are therefore less prone to antimicrobial resistance (AMR) compared to conventional antibiotics. However, there are still many challenges in the clinical application of the naturally occurring AMPs which necessitates further studies to establish the relationship between the chemical structure of AMPs and their antimicrobial activity and selectivity. Herein, we report a study on the relationship between the chemical structure and the biological activity of a series of rationally designed AMPs derived from Ponericin-W1, a naturally occurring AMP from ants. The peptides were designed by modification of the hydrophobic and hydrophilic regions of the lead peptide sequence in a systematic way. Their antibacterial and hemolytic activities were determined in vitro. The antibacterial activity of a representative peptide, At5 was also tested in a mouse model of skin wound infection. Furthermore, the relationship between the physicochemical properties of the peptides and their antibacterial activity was investigated. Replacing the cationic amino acids in the hydrophobic region of the peptides with hydrophobic amino acids enhanced their antibacterial activity and increasing the number of cationic amino acids in the hydrophilic region reduced their toxicity to human red blood cells and thus improved their selectivity for bacteria. Four of the designed peptides, coded as At3, At5, At8, and At10, displayed considerable antibacterial activity and high selectivity for bacteria. At5 also accelerated the wound healing in mice indicating high in vivo efficiency of this peptide. The peptides were more effective against Gram-negative bacteria and no AMR was developed against them in the bacteria even after 25 generations. The results from this study can provide a better understanding of the structural features required for strong antibacterial activity and selectivity, and serve as a guide for the future rational design of AMPs.

Antimicrobial peptide functionalized gold nanorods combining near-infrared photothermal therapy for effective wound healing.

Photothermal therapy using laser activated gold nanorods (AuNRs) is a strategy for treatment of bacterial infections. Nevertheless, it also exerts cytotoxicity against human cells which leads to adverse effects in healthy human tissues and limits the applicable dose. Functionalization of AuNRs with a selective antimicrobial peptide (AMP) with higher selectivity for bacteria over human cells is a promising strategy for increasing the selectivity of the AuNRs for bacteria, hence increasing their cellular uptake by the bacteria in order to achieve stronger antimicrobial effects with lower doses of AuNRs without damaging the human cells. In this study, the surface of AuNRs was functionalized with a short AMP named C-At5 and the efficiency of the peptide functionalized AuNRs in killing gram-positive and gram-negative bacteria was evaluated in vitro as well as their potential for facilitating wound healing in a mouse model of wound infection with and without application of laser. The peptide-conjugated AuNRs exhibited higher antibacterial activity in vitro compared to the plain AuNRs both in the presence and absence of laser irradiation. Furthermore, AuNR@C-At5 had very low toxicity against human skin fibroblasts and human red blood cells indicating their higher biocompatibility compared to the plain AuNRs. Treatment of wounded mice with AuNR@C-At5 accelerated the wound healing process which was further enhanced by applying laser. The system developed in this study has great potential for customization for specific antimicrobial or antifungal therapy via conjugation of different types of AMPs with higher selectivity and can therefore serve as a guide for any future attempts in this regard.

Anticancer effect of rationally designed α-helical amphiphilic peptides.

Anticancer peptides (ACPs) have attracted increasing attention in cancer therapy due to their unique mechanism of action on cancer cells. The main challenge is to establish the correlation between their physicochemical properties and their selectivity and anticancer effect, leading to a clear design strategy. In this study, a series of new α-helical short peptides (coded At1-At12) with different anticancer activities were systematically designed with different amphiphilicity based on a natural α-helical antimicrobial peptide (AMP) derived from ant. Three of the designed peptides, At7, At10 and At11, showed considerable anticancer activity with low toxicity to normal skin fibroblasts. The high selectivity of the peptides is attributed to their balanced amphiphilicity and cationic nature which favours binding to the outer membrane of negatively charged cancer cells over the neutral membrane of normal mammalian cells. In addition to rapid membrane penetration, the designed peptides also damaged the mitochondria and induced mitochondrial membrane depolarization. Moreover, these peptides were found to induce apoptosis in cancer cells by up-regulating the expression of apoptotic proteins Bax and Caspase-3, down-regulating the apoptotic protein Bcl-2, and activating the Caspase enzyme-linked reaction. The results of this study reveal the potential of these peptides for clinical applications, and provide a guidance for further development of highly selective anticancer medications.

Enhanced In Vitro and In Vivo Efficacy of Alginate/Silk Protein/Hyaluronic Acid with Polypeptide Microsphere Delivery for Tissue Regeneration of Articular Cartilage.

Alginate/Silk fibroin/hyaluronic acid (ALG/SF/HA) nanocomposites were synthesised using blending, inter-linking, and lyophilization methods. We investigated the physicochemical properties of the resulting nanocomposites, including their water retention, weight loss, porosity and cytocompatibility. The optimum ratios of the ALG/SF/HA scaffolding were 3:6.5:0.5. Nanocomposites with optimum ratios were then prepared by integrating pilose antler polypeptides (PAPS) to poly(lactic-co-glycolic acid) (PLGA) microspheres, and the performance was investigated. PAPS-ALG/SF/HA nanocomposites exhibited desirable adhesions and proliferations. Rabbit cartilage deficiencies was developed by the animal model. The cartilage repair effects deficiencies were detected and analyzed between PAPS-SF/ALG/ALG/SF/HA, and control activity classes. The deficiencies were virtually fully remedied after 13 weeks in the presence of PAPS-ALG/SF/HA class, suggesting that the PAPS-ALG/SF/HA nanocomposites had a positive effects on joint cartilage repair.

Plasticizer and catalyst co-functionalized PEDOT:PSS enables stretchable electrochemical sensing of living cells.

Recently, stretchable electrochemical sensors have stood out as a powerful tool for the detection of soft cells and tissues, since they could perfectly comply with the deformation of living organisms and synchronously monitor mechanically evoked biomolecule release. However, existing strategies for the fabrication of stretchable electrochemical sensors still face with huge challenges due to scarce electrode materials, demanding processing techniques and great complexity in further functionalization. Herein, we report a novel and facile strategy for one-step preparation of stretchable electrochemical biosensors by doping ionic liquid and catalyst into a conductive polymer (poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate), PEDOT:PSS). Bis(trifluoromethane) sulfonimide lithium salt as a small-molecule plasticizer can significantly improve the stretchability and conductivity of the PEDOT:PSS film, and cobalt phthalocyanine as an electrocatalyst endows the film with excellent electrochemical sensing performance. Moreover, the functionalized PEDOT:PSS retained good cell biocompatibility with two extra dopants. These satisfactory properties allowed the real-time monitoring of stretch-induced transient hydrogen peroxide release from cells. This work presents a versatile strategy to fabricate conductive polymer-based stretchable electrodes with easy processing and excellent performance, which benefits the in-depth exploration of sophisticated life activities by electrochemical sensing.

One-Step Microfluidic Fabrication of Multi-Responsive Liposomes for Targeted Delivery of Doxorubicin Synergism with Photothermal Effect.

INTRODUCTION: Cancer of the bladder is one of the most common and life-threatening. Compared with traditional delivery methods, intravesical administration reduces the amount of drugs required, increases the amount of drugs reaching the lesion site, and minimizes systemic exposure to therapeutic agents. To overcome the limitations of urinary voiding, low urothelium permeability, and intermittent catheterization for large dilution and irrigation of drugs in the bladder, magnetic and photothermal-responsive folate receptor-targeted thermal liposomes (FA-TMLs) were designed for the targeted delivery of doxorubicin (DOX) to bladder cancer cells. METHODS: Through a microfluidic mixer chip, the magnetic nanoparticles (MNPs), gold nanorods (GNRs) and DOX were encapsulated in folate-modified thermosensitive liposomes to form FA-TMLs@MNPs-GNRs-DOX. DLS, TEM, DSC, and magnetic hysteresis loop were used to characterize the construction of FA-TMLs@MNPs-GNRs-DOX. RESULTS: FA-TMLs@MNPs-GNRs-DOX had a size of about 230 nm and exhibited superparamagnetic properties with the saturation magnetization of 20 emu/g. The DOX loading capacity was as high as 0.57 mg/mL. Additionally, drug release of the FA-TMLs@MNPs-GNRs-DOX could be controlled by temperature change through the photothermal effect. A 980 nm laser beam was selectively irradiated on the FA-TMLs@MNPs-GNRs-DOX to trigger the structural changes of the FA-TMLs, and an average of 95% of the drug was released after 3 hours. The results of cell uptake experiments reveal indicated that FA-TMLs@MNPs-GNRs-DOX were able to specifically bind folate-receptor-positive cells and exhibited toxicity to bladder tumor cells. CONCLUSION: The present results suggest FA-TMLs@MNPs-GNRs-DOX have a promising multifunctional response and can act as an ideal multifunctional drug delivery system (DDS) for the treatment of bladder tumors.

Correction: Plasticizer and catalyst co-functionalized PEDOT:PSS enables stretchable electrochemical sensing of living cells.

[This corrects the article DOI: 10.1039/D1SC04138J.].

Electrospun Icariin-Loaded Core-Shell Collagen, Polycaprolactone, Hydroxyapatite Composite Scaffolds for the Repair of Rabbit Tibia Bone Defects.

BACKGROUND: Electrospinning is a widely used technology that can produce scaffolds with high porosity and surface area for bone regeneration. However, the small pore sizes in electrospun scaffolds constrain cell growth and tissue-ingrowth. In this study, novel drug-loading core-shell scaffolds were fabricated via electrospinning and freeze drying to facilitate the repair of tibia bone defects in rabbit models. MATERIALS AND METHODS: The collagen core scaffolds were freeze-dried containing icariin (ICA)-loaded chitosan microspheres. The shell scaffolds were electrospun using collagen, polycaprolactone and hydroxyapatite materials to form CPH composite scaffolds with the ones containing ICA microspheres named CPHI. The core-shell scaffolds were then cross-linked by genipin. The morphology, microstructure, physical and mechanical properties of the scaffolds were assessed. Rat marrow mesenchymal stem cells from the wistar rat were cultured with the scaffolds. The cell adhesion and proliferation were analysed. Adult rabbit models with tibial plateau defects were used to evaluate the performance of these scaffolds in repairing the bone defects over 4 to 12 weeks. RESULTS: The results reveal that the novel drug-loading core-shell scaffolds were successfully fabricated, which showed good physical and chemical properties and appropriate mechanical properties. Furthermore, excellent cells attachment was observed on the CPHI scaffolds. The results from radiography, micro-computed tomography, histological and immunohistochemical analysis demonstrated that abundant new bones were formed on the CPHI scaffolds. CONCLUSION: These new core-shell composite scaffolds have great potential for bone tissue engineering applications and may lead to effective bone regeneration and repair.