arXiv subjects

Giuseppe Tronci

Publications and source records attributed to Giuseppe Tronci.

At least 37 records · Page 2Linked to original sources

arXiv2021

Hydrolytic Degradability, Cell Tolerance and On-Demand Antibacterial Effect of Electrospun Photodynamically Active Fibres

Photodynamically active fibres (PAFs) are a novel class of stimulus-sensitive systems capable of triggering antibiotic-free antibacterial effect on-demand when exposed to light. Despite their relevance in infection control, however, the broad clinical applicability of PAFs has not yet been fully realised due to the limited control in fibrous microstructure, cell tolerance and antibacterial activity in the physiologic environment. We addressed this challenge by creating semicrystalline electrospun fibres with varying content of poly[(L-lactide)-co-(glycolide)] (PLGA), poly(epsilon-caprolactone) (PCL) and methylene blue (MB), whereby the effect of polymer morphology, fibre composition and photosensitiser (PS) uptake on wet state fibre behaviour and functions was studied. The presence of crystalline domains and PS-polymer secondary interactions proved key to accomplishing long-lasting fibrous microstructure, controlled mass loss and controlled MB release profiles (37 degC, pH 7.4, 8 weeks). PAFs with equivalent PLGA:PCL weight ratio successfully promoted attachment and proliferation of L929 cells over a 7-day culture with and without light activation, while triggering up to 2.5 and 4 log reduction in E. coli and S. mutans viability, respectively. These results support the therapeutic applicability of PAFs for frequently encountered bacterial infections, opening up new opportunities in photodynamic fibrous systems with integrated wound healing and infection control capabilities.

q-bio.TO↗

arXiv2019

Rotation-assisted wet-spinning of UV-cured gelatin fibres and nonwovens

Photoinduced network formation is an attractive strategy for designing water-insoluble gelatin fibres as medical device building blocks and for enabling late-stage property customisation. However, mechanically-competent, long-lasting filaments are still hard to realise with current photoactive, e.g. methacrylated, gelatin systems due to inherent spinning instability and restricted coagulation capability. To explore this challenge, we present a multiscale approach combining the synthesis of 4-vinylbenzyl chloride (4VBC)-functionalised gelatin (Gel-4VBC) with a voltage-free spinning and UV-curing process so that biopolymer networks in the form of either individual fibres or nonwovens could be successfully manufactured. In comparison to state-of-the-art methacrylated gelatin, the mechanical properties of UV-cured Gel-4VBC fibres were readily modulated by adjustment of coagulation conditions, so that an ultimate tensile strength and strain at break of up to ~80 MPa and ~9 % were measured, respectively. The sequential functionalisation /spinning route proved to be highly scalable, so that one step spunlaid formation of fibroblast-friendly nonwoven fabrics was successfully demonstrated with wet spun Gel-4VBC fibres. The presented approach could be exploited to generate a library of gelatin building blocks tuneable from the molecular to the macroscopic level to deliver computer-controlled extrusion of fibres and nonwovens according to defined clinical applications.

physics.chem-ph↗

arXiv2019

Two-layer Electrospun System Enabling Wound Exudate Management and Visual Infection Response

The spread of antimicrobial resistance calls for chronic wound management devices that can engage with the wound exudate and signal infection by prompt visual effects. Here, the manufacture of a two-layer fibrous device with independently-controlled exudate management capability and visual infection responsivity was investigated by sequential free surface electrospinning of poly(methyl methacrylate-co-methacrylic acid) (PMMA-co-MAA) and poly(acrylic acid) (PAA). By selecting wound pH as infection indicator, PMMA-co-MAA fibres were encapsulated with halochromic bromothymol blue (BTB) to trigger colour changes at infection-induced alkaline pH. Likewise, the exudate management capability was integrated via the synthesis of a thermally-crosslinked network in electrospun PAA layer. PMMA-co-MAA fibres revealed high BTB loading efficiency (> 80 wt.%) and demonstrated prompt colour change and selective dye release at infected-like media (pH > 7). The synthesis of the thermally-crosslinked PAA network successfully enabled high water uptake (up to nearly 2500 wt.%) and swelling index (up to nearly 300 a.%), in contrast to electrospun PAA controls. This dual device functionality was lost when the same building blocks were configured in a single-layer mesh of core-shell fibres, whereby significant BTB release (~ 70 wt.%) was measured even at acidic pH. This study therefore demonstrates how the fibrous configuration can be conveniently manipulated to trigger structure-induced functionalities critical to chronic wound management and monitoring.

physics.med-ph↗

arXiv2018

Monomer-induced customisation of UV-cured atelocollagen hydrogel networks

The covalent functionalisation of type I atelocollagen with either 4-vinylbenzyl or methacrylamide residues is presented as a simple synthetic strategy to achieve customisable, cell-friendly UV-cured hydrogel networks with widespread clinical applicability. Molecular parameters, i.e. the type of monomer, degree of atelocollagen functionalisation and UV curing solution, have been systematically varied and their effect on gelation kinetics, swelling behaviour, elastic properties and enzymatic degradability investigated. UV-cured hydrogel networks deriving from atelocollagen precursors functionalised with equivalent molar content of 4-vinylbenzyl and methacrylamide adducts proved to display remarkably-different swelling ratio, storage modulus and collagenase resistance, similarly to the case of UV-cured hydrogel networks obtained with the same type of methacrylamide adduct, but varied degree of functionalisation. UV-induced network formation of 4VBC functionalised atelocollagen molecules yielded hydrogels with increased stiffness and enzymatic stability, attributed to the molecular rigidity of resulting aromatised crosslinking segment, whilst no toxic response was observed with osteosarcoma G292 cells. Although to a lesser extent, the pH of the UV-curing solution also proved to affect macroscopic hydrogel properties, likely due to the altered organisation of atelocollagen molecules during network formation. By leveraging the knowledge gained with classic synthetic networks, this study highlights how the type of monomer can be conveniently exploited to realise customisable atelocollagen hydrogels with controlled structure-property relationships to meet the requirements of unmet clinical applications.

q-bio.BM↗

arXiv2018

A UV-cured nanofibrous membrane of vinylbenzylated gelatin-poly(ε-caprolactone) dimethacrylate co-network by scalable free surface electrospinning

Electrospun nanofibrous membranes of natural polymers, such as gelatin, are fundamental in the design of regenerative devices. Crosslinking of electrospun fibres from gelatin is required to prevent dissolution in water, to retain the original nanofibre morphology after immersion in water, and to improve the thermal and mechanical properties, although this is still challenging to accomplish in a controlled fashion. In this study, we have investigated the scalable manufacture and structural stability in aqueous environment of a UV-cured nanofibrous membrane fabricated by free surface electrospinning (FSES) of aqueous solutions containing vinylbenzylated gelatin and poly(epsilon-caprolactone) dimethacrylate (PCL-DMA). Vinylbenzylated gelatin was obtained via chemical functionalisation with photopolymerisable 4-vinylbenzyl chloride (4VBC) groups, so that the gelatin and PCL phase in electrospun fibres were integrated in a covalent UV-cured co-network at the molecular scale, rather than being simply physically mixed. UV-cured nanofibrous membranes did not dissolve in water and showed enhanced thermal and mechanical properties, with respect to as-spun samples, indicating the effectiveness of the photo-crosslinking reaction. In addition, UV-cured gelatin/PCL membranes displayed increased structural stability in water with respect to PCL-free samples and were highly tolerated by G292 osteosarcoma cells. These results therefore support the use of PCL DMA as hydrophobic, biodegradable crosslinker and provide new insight on the scalable design of water insoluble, mechanical competent gelatin membranes for healthcare applications.

physics.app-ph↗

arXiv2018

The application of collagen in advanced wound dressings

Chronic wounds fail to proceed through an orderly and timely self healing process, resulting in cutaneous damage with full thickness in depth and leading to a major healthcare and economic burden worldwide. In the UK alone, 200,000 patients suffer from a chronic wound, whilst the global advanced wound care market is expected to reach nearly $11 million in 2022. Despite extensive research efforts so far, clinically-approved chronic wound therapies are still time-consuming, economically unaffordable and present restricted customisation. In this chapter, the role of collagen in the extracellular matrix of biological tissues and wound healing will be discussed, together with its use as building block for the manufacture of advanced wound dressings. Commercially-available collagen dressings and respective clinical performance will be presented, followed by an overview on the latest research advances in the context of multifunctional collagen systems for advanced wound care.

q-bio.TO↗

arXiv2017

Antibacterial properties of nonwoven wound dressings coated with Manuka honey or methylglyoxal

Manuka honey (MH) is used as an antibacterial agent in bioactive wound dressings via direct impregnation onto a suitable substrate. MH provides unique antibacterial activity when compared with conventional honeys, owing partly to one of its constituents, methylglyoxal (MGO). Aiming to investigate an antibiotic-free antimicrobial strategy, we studied the antibacterial activity of both MH and MGO (at equivalent MGO concentrations) when applied as a physical coating to a nonwoven fabric wound dressing. When physically coated on to a cellulosic hydroentangled nonwoven fabric, it was found that concentrations of 0.0054 mg cm-2 of MGO in the form of MH and MGO was sufficient to achieve 100 CFU% bacteria reduction against gram-positive Staphylococcus aureus and gram-negative Klebsiella pneumoniae, based on BS EN ISO 20743:2007. A 3- to 20- fold increase in MGO concentration (0.0170 - 0.1 mg cm-2) was required to facilitate a good antibacterial effect (based on BS EN ISO 20645:2004) in terms of zone of inhibition and lack of growth under the sample. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was also assessed for MGO in liquid form against three prevalent wound and healthcare-associated pathogens, i.e. Staphylococcus aureus, gram-negative Pseudomonas aeruginosa and gram-positive Enterococcus faecalis. Other than the case of MGO-containing fabrics, solutions with much higher MGO concentrations (128 mg L-1 - 1024 mg L-1) were required to provide either a bacteriostatic or bactericidal effect. The results presented in this study therefore demonstrate the relevance of MGO-based coating as an environment-friendly strategy for the design of functional dressings with antibiotic-free antimicrobial chemistries.

q-bio.QM↗

arXiv2017

Thiol-ene photo-click collagen-PEG hydrogels: impact of water-soluble photoinitiators on cell viability, gelation kinetics and rheological properties

Thiol-ene photo-click hydrogels were prepared via step-growth polymerisation using thiol-functionalised type-I collagen and 8-arm poly(ethylene glycol) norbornene terminated (PEG-NB), as a potential injectable regenerative device. Type-I collagen was thiol-functionalised by a ring opening reaction with 2-iminothiolane (2IT), whereby up to 80 Abs% functionalisation and 90 RPN% triple helical preservation were recorded via 2,4,6-Trinitrobenzenesulfonic acid (TNBS) colorimetric assay and circular dichroism (CD). Type, i.e. 2-Hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone (I2959) or lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP), and concentration of photoinitiator were varied to ensure minimal photoinitiator-induced cytotoxicity and to enable thiol-ene network formation of collagen-PEG mixtures. The viability of G292 cells following 24 h culture in photoinitiator-supplemented media was largely affected by the photoinitiator concentration, with I2959-supplemented media observed to induce higher toxic response compared to LAP-supplemented media. In line with the in vitro study, selected photoinitiator concentrations were used to prepare thiol-ene photo-click hydrogels. Gelation kinetics proved to be largely affected by the specific photoinitiator, with LAP-containing thiol-ene mixtures leading to significantly reduced complete gelation time with respect to I2959-containing mixtures. Other than the specific photoinitiator, the photoinitiator concentration was key to adjust hydrogel storage modulus (G'), whereby 15-fold G' increase was observed in samples prepared with 0.5% (w/v) compared to 0.1% (w/v) LAP. The photoinitiator-gelation-cytotoxicity relationships established in this study will be instrumental to the design of orthogonal collagen-based niches for regenerative medicine.

physics.chem-ph↗

arXiv2017

Influence of telopeptides on the structural and physical properties of polymeric and monomeric acid-soluble type I collagen

Currently two factors hinder the use of collagen as building block of regenerative devices: the potential antigenicity, and limited mechanical strength in aqueous environment. Polymeric collagen is naturally found in the cross-linked state and is mechanically tougher than the monomeric, cross-link-free (acid-soluble) collagen ex vivo. The antigenicity of collagen, on the other hand, is mainly ascribed to inter-species variations in amino acid sequences, which are primarily located in the non-helical terminal telopeptides. Although these can be removed through enzymatic treatment to produce atelocollagen, the effect of telopeptide removal on triple helix organization, amino acidic composition and thermal properties is often disregarded. Here, we compare the structural, chemical and physical properties of polymeric and monomeric type I collagen with and without telopeptides, in an effort to elucidate the influence that either covalent crosslinks or telopeptides possess. Circular dichroism (CD) was used to examine the triple helical conformation and quantify the denaturation temperature (Td) of both monomeric collagen (36.5 °C) and monomeric atelocollagen (35.5 °C). CD measurements were combined with differential scanning calorimetry (DSC) in order to gain insight into the triple helix-to-coil thermal transition and shrinkage temperature (Ts) of polymeric atelo collagen (44.8 °C), polymeric collagen (62.7 °C), monomeric atelo collagen (51.4 °C) and monomeric collagen (66.5 °C). Structural and thermal analyses were combined with high pressure liquid chromatography (HPLC) to determine the content of specific collagen amino acidic residues used as markers for the presence of telopeptides and mature crosslinks.

physics.chem-ph↗

arXiv2016

Hydrolytic and lysozymic degradability of chitosan systems with heparin-mimicking pendant groups

Chitosan (CT) is an antibacterial polysaccharide that has been investigated for drug carriers, haemostats and wound dressings. For these applications, customised CT devices can often be obtained with specific experimental conditions, which can irreversibly alter native biopolymer properties and functions and lead to unreliable material behaviour. In order to investigate the structure-function relationships in CT covalent networks, monosodium 5-sulfoisophthalate (PhS) was selected as heparin-mimicking, growth factor-binding crosslinking segment, whilst 1,4-phenylenediacetic acid (4Ph) and poly(ethylene glycol) bis(carboxymethyl) ether (PEG) were employed as sulfonic acid-free diacids of low and high crosslinker length respectively. Hydrogels based on short crosslinkers (PhS and 4Ph) displayed increased crosslink density, decreased swelling ratio as well as minimal hydrolytic and lysozymic degradation, whilst addition of lysozymes to PEG based networks resulted in 70 wt.-% mass loss. PhS-crosslinked CT hydrogels displayed the highest loss (40 +/- 6 CFU%) of antibacterial activity upon incubation with Porphyromonas gingivalis, whilst respective extracts were tolerated by L929 mouse fibroblasts.

cond-mat.soft↗

arXiv2016

Nonwoven scaffolds for bone regeneration

Developing successful scaffolds requires clinicians to adopt a multidisciplinary approach in order to understand and stimulate the natural bone regeneration process. A variety of natural and synthetic biomaterials, including naturally extracted, chemically functionalised collagen and synthetic Poly(epsilon-caprolactone) (PCL), can be manufactured into fibres, enabling the formation of nonwoven scaffolds. Many different nonwoven architectures and structural features can then be introduced, depending on the manufacturing parameters. This chapter introduces methods for producing scaffolds with appropriate pore sizes by means of electrospinning, and it outlines the opportunities that exist for other nonwoven manufacturing technologies in the development of biomimetic products.

q-bio.TO↗

arXiv2016

In silico modeling of the rheological properties of covalently crosslinked collagen triple helices

Biomimetic hydrogels based on natural polymers are a promising class of biomaterial, mimicking the natural extra-cellular matrix of biological tissues and providing cues for cell attachment, proliferation and differentiation. With a view to providing an upstream method to guide subsequent experimental design, the aim of this study was to introduce a mathematical model that described the rheological properties of a hydrogel system based on covalently crosslinked collagen triple helices. In light of their organization, such gels exhibit limited collagen bundling that cannot be described by existing fibril network models. The model presented here treats collagen triple helices as discrete semi-flexible polymers, permits full access to metrics for network microstructure, and should provide a comprehensive understanding of the parameter space associated with the development of such multi-functional materials. Triple helical hydrogel networks were experimentally obtained via reaction of type I collagen with both aromatic and aliphatic diacids. The complex modulus G* was found from rheological testing in linear shear and quantitatively compared to model predictions. In silico data from the computational model successfully described the experimental trends in hydrogel storage modulus with either (i) the concentration of collagen triple helices during crosslinking reaction or (ii) the type of crosslinking segment introduced in resulting hydrogel networks. This approach may pave the way to a step change in the rational design of biomimetic triple helical collagen systems with controlled multi-functionality.

cond-mat.soft↗

arXiv2016

A Structurally Self-Assembled Peptide Nano-Architecture by One-Step Electrospinning

Self-assembling peptides (SAPs) have shown to offer great promise in therapeutics and have the ability to undergo self-assembly and form ordered nanostructures. However SAP gels are often associated with inherent weak and transient mechanical properties and incorporation of them into polymeric matrices is a route to enhance their mechanical stability. The aim of this work was to incorporate P11-8 peptide (CH3COQQRFOWOFEQQNH2) within poly(epsilon-caprolactone) (PCL) fibrous webs via one-step electrospinning, aiming to establish the underlying relationships between spinning process, molecular peptide conformation, and material internal architecture. Electrospinning of PCL solutions (6% w/w) in hexafluoro-2-propanol (HFIP) containing up to 40 mg/ml P11-8 resulted in the formation of fibres in both nano- (10-100 nm) and submicron range (100-700 nm), in contrast to PCL only webs, which displayed a predominantly submicron fibre distribution. FTIR and CD spectroscopy on both PCL/peptide solutions and resulting electrospun webs revealed monomeric and beta-sheet secondary conformation, respectively, suggesting the occurrence of peptide self-assembly during electrospinning due to solvent evaporation. The peptide concentration (0 -> 40 mg/ml) was found to primarily affect the internal structure of the fabric at the nano-scale, whilst water as well as cell culture medium contact angles were dramatically decreased. Nearly no cytotoxic response (> 90% cell viability) was observed when L929 mouse fibroblasts were cultured in contact with electrospun peptide loaded samples. This novel nanofibrous architecture may be the basis for an interesting material platform for e.g. hard tissue repair, in light of the presence of the self assembled P11-8 in the PCL fibrous structure.

cond-mat.soft↗

arXiv2016

Protease-sensitive atelocollagen hydrogels promote healing in a diabetic wound model

The design of exudate-managing wound dressings is an established route to accelerated healing, although such design remains a challenge from material and manufacturing standpoints. Aiming towards the clinical translation of knowledge gained in vitro with highly swollen rat tail collagen hydrogels, this study investigated the healing capability in a diabetic mouse wound model of telopeptide-free, protease-inhibiting collagen networks. 4 vinylbenzylation and UV irradiation of type I atelocollagen (AC) led to hydrogel networks with chemical and macroscopic properties comparable to previous collagen analogues, attributable to similar lysine content and dichroic properties. After 4 days in vitro, hydrogels induced nearly 50 RFU% reduction in matrix metalloproteinase (MMP)-9 activity, whilst showing less than 20 wt.-% weight loss. After 20 days in vivo, dry networks promoted 99% closure of 10x10 mm full thickness wounds and accelerated neodermal tissue formation compared to Mepilex. This collagen system can be equipped with multiple, customisable properties and functions key to personalised chronic wound care.

physics.bio-ph↗

arXiv2016

An investigation into the nano-/micro-architecture of electrospun poly (ε-caprolactone) and self-assembling peptide fibers

Self-assembling peptides (SAPs) have the ability to spontaneously assemble into ordered nanostructures enabling the manufacture of "designer" nanomaterials. The reversible molecular association of SAPs has been shown to offer great promise in therapeutics via for example, the design of biomimetic assemblies for hard tissue regeneration. This could be further exploited for novel nano/micro diagnostic tools. However, self-assembled peptide gels are often associated with inherent weak and transient mechanical properties. Their incorporation into polymeric matrices has been considered as a potential strategy to enhance their mechanical stability. This study focuses on the incorporation of an 11-residue peptide, P11-8 (peptide sequence: CH3CO-Gln-Gln-Arg-Phe-Orn-Trp-Orn-Phe-Glu-Gln-Gln-NH2) within a fibrous scaffold of poly (ε-caprolactone) (PCL). In this study an electrospinning technique was used to fabricate a biomimetic porous scaffold out of a solution of P11-8 and PCL which resulted in a biphasic structure composed of submicron fibers (diameter of 100-700 nm) and nanofibers (diameter of 10-100 nm). The internal morphology of the fabric and its micro-structure can be easily controlled by changing the peptide concentration. The secondary conformation of P11-8 was investigated in the as-spun fibers by ATR-FTIR spectroscopy and it is shown that peptide self-assembly into \{b}eta-sheet tapes has taken place during fiber formation and the deposition of the fibrous web.

cond-mat.mtrl-sci↗

arXiv2015

Influence of 4-vinylbenzylation on the rheological and swelling properties of photo-activated collagen hydrogels

Covalent functionalisation of collagen has been shown to be a promising strategy to adjust the mechanical properties of highly swollen collagen hydrogels. At the same time, secondary interactions between for example, amino acidic terminations or introduced functional groups also play an important role and are often challenging to predict and control. To explore this challenge, 4-vinylbenzyl chloride (4VBC) and methacrylic anhydride (MA) were reacted with type I collagen, and the swelling and rheological properties of resulting photo activated hydrogel systems investigated. 4VBC-based hydrogels showed significantly increased swelling ratio, in light of the lower degree of collagen functionalisation, with respect to methacrylated collagen networks, whilst rheological storage moduli were found to be comparable between the two systems. To explore the role of benzyl groups in the mechanical properties of the 4VBC-based collagen system, model chemical force microscopy (CFM) was carried out in aqueous environment with an aromatised probe against an aromatised gold coated glass slide. A marked increase in adhesion force (F: 0.11 +/- 0.01 nN) was measured between aromatised samples, compared to the adhesion force observed between the non-modified probe and a glass substrate (F: 2.64 +/- 1.82 nN). These results suggest the formation of additional and reversible π-π stacking interactions in aromatic 4VBC-based networks and explain the remarkable rheological properties of this system in comparison to MA based hydrogels.

physics.chem-ph↗

arXiv2015

Biomimetic wet-stable fibres via wet spinning and diacid-based crosslinking of collagen triple helices

One of the limitations of electrospun collagen as bone-like fibrous structure is the potential collagen triple helix denaturation in the fibre state and the corresponding inadequate wet stability even after crosslinking. Here, we have demonstrated the feasibility of accomplishing wet-stable fibres by wet spinning and diacid-based crosslinking of collagen triple helices, whereby fibre ability to act as bone-mimicking mineralisation system has also been explored. Circular dichroism (CD) demonstrated nearly complete triple helix retention in resulting wet-spun fibres, and the corresponding chemically crosslinked fibres successfully preserved their fibrous morphology following 1-week incubation in phosphate buffer solution (PBS). The presented novel diacid-based crosslinking route imparted superior tensile modulus and strength to the resulting fibres indicating that covalent functionalization of distant collagen molecules is unlikely to be accomplished by current state-of-the-art carbodiimide-based crosslinking. To mimic the constituents of natural bone extra cellular matrix (ECM), the crosslinked fibres were coated with carbonated hydroxyapatite (CHA) through biomimetic precipitation, resulting in an attractive biomaterial for guided bone regeneration (GBR), e.g. in bony defects of the maxillofacial region.

physics.bio-ph↗

arXiv2015

Compositional and in Vitro Evaluation of Nonwoven Type I Collagen/Poly-dl-lactic Acid Scaffolds for Bone Regeneration

Poly-dl-lactic acid (PDLLA) was blended with type I collagen to attempt to overcome the instantaneous gelation of electrospun collagen scaffolds in biological environments. Scaffolds based on blends of type I collagen and PDLLA were investigated for material stability in cell culture conditions (37 °C; 5% CO2) in which post-electrospinning glutaraldehyde crosslinking was also applied. The resulting wet-stable webs were cultured with bone marrow stromal cells (HBMSC) for five weeks. Scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), Fourier transform infra-red spectroscopy (FTIR) and biochemical assays were used to characterise the scaffolds and the consequent cell-scaffold constructs. To investigate any electrospinning-induced denaturation of collagen, identical PDLLA/collagen and PDLLA/gelatine blends were electrospun and their potential to promote osteogenic differentiation investigated. PDLLA/collagen blends with w/w ratios of 40/60, 60/40 and 80/20 resulted in satisfactory wet stabilities in a humid environment, although chemical crosslinking was essential to ensure long term material cell culture. Scaffolds of PDLLA/collagen at a 60:40 weight ratio provided the greatest stability over a five-week culture period. The PDLLA/collagen scaffolds promoted greater cell proliferation and osteogenic differentiation compared to HMBSCs seeded on the corresponding PDLLA/gelatine scaffolds, suggesting that any electrospinning-induced collagen denaturation did not affect material biofunctionality within 5 weeks in vitro.

physics.bio-ph↗