Fluorinated GlycoNucleoLipid-based hydrogels as new spatiotemporal stimulable DDS

Achieving a controlled release of several active pharmaceutical ingredients (APIs) remains a challenge for improving their therapeutic effects and reduced their side effects. In the current work, stimulable Drug Delivery Systems (DDS) based on supramolecular hydrogels were designed by combining two APIs featuring anticancer activities, namely the doxorubicin and phenazine 14. In vitro studies revealed promising physicochemical properties for all the investigated API loaded gels. Fluorinated GlycoNucleoLipid (GNF) based supramolecular gels remain stable in the presence of either doxorubicin (Doxo) or phenazine 14 (Phe) as anticancer drugs. Noteworthy, the stiffness of the GNF-based supramolecular gels was enhanced in the presence of both APIs while maintaining their thixotropic properties. We demonstrated that the storage modulus (G') of the GNF gels was increased from 1.3 kPa to 9.3 kPa upon loading of both APIs within the same gels. With a low mechanical stimulation (within the LVR), a passive diffusion out of gels was observed for Dox whereas Phe remained trapped in the GNF gels over several hours. Also, in this work we showed that mechanical stress triggered the release of both Phe and Doxo at different rates.

The cell-assembled extracellular matrix: A focus on the storage stability and terminal sterilization of this human "bio" material

The Cell-Assembled extracellular Matrix (CAM) is an attractive biomaterial because it provided the backbone of vascular grafts that were successfully implanted in patients, and because it can now be assembled in "human textiles". For future clinical development, it is important to consider key manufacturing questions. In this study, the impact of various storage conditions and sterilization methods were evaluated. After 1 year of dry frozen storage, no change in mechanical nor physicochemical properties were detected. However, storage at 4 °C and room temperature resulted in some mechanical changes, especially for dry CAM, but physicochemical changes were minor. Sterilization modified CAM mechanical and physicochemical properties marginally except for hydrated gamma treatment. All sterilized CAM supported cell proliferation. CAM ribbons were implanted subcutaneously in immunodeficient rats to assess the impact of sterilization on the innate immune response. Sterilization accelerated strength loss but no significant difference could be shown at 10 months. Very mild and transient inflammatory responses were observed. Supercritical CO2 sterilization had the least effect. In conclusion, the CAM is a promising biomaterial since it is unaffected by long-term storage in conditions available in hospitals (hydrated at 4 °C), and can be sterilized terminally (scCO2) without compromising in vitro nor in vivo performance. STATEMENT OF SIGNIFICANCE: In the field of tissue engineering, the use of extracellular matrix (ECM) proteins as a scaffolding biomaterial has become very popular. Recently, many investigators have focused on ECM produced by cells in vitro to produce unprocessed biological scaffolds. As this new kind of "biomaterial" becomes more and more relevant, it is critical to consider key manufacturing questions to facilitate future transition to the clinic. This article presents an extensive evaluation of long-term storage stability and terminal sterilization effects on an extracellular matrix assembled by cells in vitro. We believe that this article will be of great interest to help tissue engineers involved in so-called scaffold-free approaches to better prepare the translation from benchtop to bedside.

Electropolymerizable Thiophene-Oligonucleotides for Electrode Functionalization

Inserting complex biomolecules such as oligonucleotides during the synthesis of polymers remains an important challenge in the development of functionalized materials. In order to engineer such a biofunctionalized interface, a single-step method for the covalent immobilization of oligonucleotides (ONs) based on novel electropolymerizable lipid thiophene-oligonucleotide (L-ThON) conjugates was employed. Here, we report a new thiophene phosphoramidite building block for the synthesis of modified L-ThONs. The biofunctionalized material was obtained by direct electropolymerization of L-ThONs in the presence of 2,2'-bithiophene (BTh) to obtain a copolymer film on indium tin oxide electrodes. In situ electroconductance measurements and microstructural studies showed that the L-ThON was incorporated in the BTh copolymer backbone. Furthermore, the covalently immobilized L-ThON sequence showed selectivity in subsequent hybridization processes with a complementary target, demonstrating that L-ThONs can directly be used for manufacturing materials via an electropolymerization strategy. These results indicate that L-ThONs are promising candidates for the development of stable ON-based bioelectrochemical platforms.

In vitroandin vivocharacterization of a novel tricalcium silicate-based ink for bone regeneration using laser-assisted bioprinting

Grafts aside, current strategies employed to overcome bone loss still fail to reproduce native tissue physiology. Among the emerging bioprinting strategies, Laser-Assisted Bioprinting (LAB) offers very high resolution, allowing designing micrometric patterns in a contactless manner, providing a reproducible tool to test ink formulation. To this date, no LAB associated ink succeeded to provide a reproducible ad integrum bone regeneration on a murine calvaria critical size defect model. Using the CE approved BioRoot RCS® as a mineral addition to a collagen-enriched ink compatible with LAB, the present study describes the process of the development of a solidifying tricalcium silicate-based ink as a new bone repair promoting substrates in a LAB model. This ink formulation was mechanically characterized by rheology to adjust it for LAB. Printed aside Stromal Cells from Apical Papilla (SCAPs), this ink demonstrated a great cytocompatibility, with significant in vitro positive impact upon cell motility, and an early osteogenic differentiation response in the absence of another stimulus. Results indicated that the in vivo application of this new ink formulation to regenerate critical size bone defect tends to promote the formation of bone volume fraction without affecting the vascularization of the neo-formed tissue. The use of LAB techniques with this ink failed to demonstrate a complete bone repair, whether SCAPs were printed or not of at its direct proximity. The relevance of the properties of this specific ink formulation would therefore rely on the quantity applied in situ as a defect filler rather than its cell modulation properties observed in vitro. For the first time, a tricalcium silicate-based printed ink, based on rheological analysis, was characterized in vitro and in vivo, giving valuable information to reach complete bone regeneration through formulation updates. This LAB-based process could be generalized to normalize the characterization of candidate ink for bone regeneration.

Oligonucleotide Solid Nucleolipid Nanoparticles against Antibiotic Resistance of ESBL-Producing Bacteria

Antibiotic resistance has become a major issue in the global healthcare system, notably in the case of Gram-negative bacteria. Recent advances in technology with oligonucleotides have an enormous potential for tackling this problem, providing their efficient intrabacterial delivery. The current work aimed to apply this strategy by using a novel nanoformulation consisting of DOTAU, a nucleolipid carrier, in an attempt to simultaneously deliver antibiotic and anti-resistance oligonucleotides. Ceftriaxone, a third-generation cephalosporin, was formulated with DOTAU to form an ion pair, and was then nanoprecipitated. The obtained solid nanocapsules were characterized using FT-IR, XRD, HPLC, TEM and DLS techniques and further functionalized by the anti-resistance ONα sequence. To obtain an optimal anti-resistance activity and encapsulation yield, both the formulation protocol and the concentration of ONα were optimized. As a result, monodispersed negatively charged nanoparticles of CFX–DOTAU-ONα with a molar ratio of 10:24:1 were obtained. The minimum inhibitory concentration of these nanoparticles on the resistant Escherichia coli strain was significantly reduced (by 75%) in comparison with that of non-vectorized ONα. All aforementioned results reveal that our nanoformulation can be considered as an efficient and relevant strategy for oligonucleotide intrabacterial delivery in the fight against antibiotic resistance.

PLGA-Based Nanoparticles for Neuroprotective Drug Delivery in Neurodegenerative Diseases

Treatment of neurodegenerative diseases has become one of the most challenging topics of the last decades due to their prevalence and increasing societal cost. The crucial point of the non-invasive therapeutic strategy for neurological disorder treatment relies on the drugs' passage through the blood-brain barrier (BBB). Indeed, this biological barrier is involved in cerebral vascular homeostasis by its tight junctions, for example. One way to overcome this limit and deliver neuroprotective substances in the brain relies on nanotechnology-based approaches. Poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) are biocompatible, non-toxic, and provide many benefits, including improved drug solubility, protection against enzymatic digestion, increased targeting efficiency, and enhanced cellular internalization. This review will present an overview of the latest findings and advances in the PLGA NP-based approach for neuroprotective drug delivery in the case of neurodegenerative disease treatment (i.e., Alzheimer's, Parkinson's, Huntington's diseases, Amyotrophic Lateral, and Multiple Sclerosis).

Hydrogel based lipid-oligonucleotides: a new route to self-delivery of therapeutic sequences

Synthetic OligoNucleotides (ON) provide promising therapeutic tools for controlling specifically genetic expression in a broad range of diseases from cancers to viral infections. Beside their chemical stability and intracellular delivery, the controlled release of therapeutic sequences remains an important challenge for successful clinical applications. In this work, Lipid-OligoNucleotide (LON) conjugates stabilizing hydrogels are reported and characterized by rheology and cryo-scanning electron microscopy (cryo-SEM). These studies revealed that lipid conjugation of antisense oligonucleotides featuring partial self-complementarity resulted in entangled pearl-necklace networks, which were obtained through micelle-micelle interaction driven by duplex formation. Owing to these properties, the Lipid AntiSense Oligonucleotide (LASO) sequences exhibited a prolonged release after subcutaneous administration compared to the non-lipidic antisense (ASO) one. The LASO self-assembly based hydrogels obtained without adjuvant represent an innovative approach for the sustained self-delivery of therapeutic oligonucleotides.

Electro-responsive hydrogels: macromolecular and supramolecular approaches in the biomedical field

Hydrogels are soft materials of the utmost importance in the biomedical and healthcare fields. Two approaches can be considered to obtain such biomaterials: the macromolecular one and the supramolecular one. In the first, the chemical gel is based on crosslinking while in the second the physical hydrogel is stabilized thanks to noncovalent interactions. Recently, new trends rely on smart devices able to modify their physico-chemical properties under stimulation. Such stimuli-responsive systems can react to internal (i.e. pH, redox potential, enzyme, etc.) or external (i.e. magnetic field, light, electric field, etc.) triggers leading to smart drug release and drug delivery systems, 3D scaffolds or biosensors. Even if some stimuli-responsive biomaterials are currently widely studied, other ones represent a real challenge. Among them, electro-responsive hydrogels, especially obtained via supramolecular approach, are under-developped leaving room for improvement. Indeed, currently known macromolecular electro-responsive systems are reaching some limitations related to their chemical composition, physicochemical properties, mechanical strength, processing technologies, etc. In contrast, the interest for supramolecular hydrogels has risen for the past few years suggesting that they may provide new solutions as electro-responsive soft materials. In this short review, we give a recent non exhaustive survey on macromolecular and supramolecular approaches for electro-responsive hydrogels in the biomedical field.

β-Galactosidase instructed self-assembly of supramolecular bolaamphiphiles hydrogelators

β-Galactosidase instructed supramolecular assemblies of Low Molecular Weight Gelators (LMWGs) derived from glyconucleo-bolaamphiphiles have been designed. These precursors, comprising galactose sensitive units at both polar heads, showed the formation of hydrogels upon the action of β-galactosidase.

Supramolecular gels derived from nucleoside based bolaamphiphiles as a light-sensitive soft material

Light-sensitive Low Molecular Weight Gelators (LMWGs) derived from glyconucleoside bolaamphiphiles containing a stilbene unit displayed gelation abilities in hydroalcoholic mixtures. These materials showed a gel-sol transition under UV irradiation thanks to E-Z isomerization of stilbene and could find potential applications as drug delivery systems.

Correction: Supramolecular gels derived from nucleoside based bolaamphiphiles as a light-sensitive soft material

Correction for ‘Supramolecular gels derived from nucleoside based bolaamphiphiles as a light-sensitive soft material’ by Julie Baillet et al., Chem. Commun., 2020, 56, 3397–3400, DOI: 10.1039/D0CC00336K.

Nucleoside-lipid-based nanocarriers for methylene blue delivery: potential application as anti-malarial drug

Nucleolipid supramolecular assemblies are promising Drug Delivery Systems (DDS), particularly for nucleic acids. Studies based on negatively and positively charged nucleolipids (diC16dT and DOTAU, respectively) demonstrated appropriate stability, safety, and purity profile to be used as DDS. Methylene Blue (MB) remains a good antimalarial drug candidate, and could be considered for the treatment of uncomplicated or severe malaria. However, the development of MB as an antimalarial drug has been hampered by a high dose regimen required to obtain a proper effect, and a short plasmatic half life. We demonstrated that nanoparticles formed by nucleolipid encapsulation of MB using diC16dT and DOTAU (MB-NPs) is an interesting approach to improve drug stability and delivery. MB-NPs displayed sizes, PDI, zeta values, and colloidal stability allowing a possible use in intravenous formulations. Nanoparticles partially protected MB from oxido-reduction reactions, thus preventing early degradation during storage, and allowing prolongated pharmacokinetic in plasma. MB-NPs' efficacy, tested in vitro on sensitive or multidrug resistant strains of Plasmodium falciparum, was statistically similar to MB alone, with a slightly lower IC₅₀. This nucleolipid-based approach to protect drugs against degradation represents a new alternative tool to be considered for malaria treatment.

Nucleolipids protects methylene blue against reduction (induced by light and chemical reductants) and do not impair antimalarial activity.

Recent Advances in the Chemistry of Glycoconjugate Amphiphiles

Glyconanoparticles essentially result from the (covalent or noncovalent) association of nanometer-scale objects with carbohydrates. Such glyconanoparticles can take many different forms and this mini review will focus only on soft materials (colloids, liposomes, gels etc.) with a special emphasis on glycolipid-derived nanomaterials and the chemistry involved for their synthesis. Also this contribution presents Low Molecular Weight Gels (LMWGs) stabilized by glycoconjugate amphiphiles. Such soft materials are likely to be of interest for different biomedical applications.

Data on iron oxide core oil-in-water nanoemulsions for atherosclerosis imaging

The data presented in this article are related to the publication entitled "Iron oxide core oil-in-water nanoemulsion as tracer for atherosclerosis MPI and MRI imaging" (Prévot et al., 2017) [1]. Herein we describe the synthesis and the characteristics of the Superparamagnetic Iron Oxide Nanoparticles (SPION) loaded inside nanoemulsions (NEs). Focus was set on obtaining SPION with narrow size distribution and close to superparamagnetic limit (20 nm) in order to reach a reasonable magnetic signal. Nanoparticles (NPs) of three different sizes were obtained (7, 11 and 18 nm) and characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), diffuse reflectance infrared Fourier transform (DRIFT) and thermogravimetric analysis (TGA). SPION were coated with oleic acid (OA) in order to load them inside the oily core of NEs droplets. SPION loaded NEs were magnetically sorted using MACS® MS Column (Miltenyi Biotec) and iron quantification was performed by UV-spectrometry measurements.

Iron oxide core oil-in-water nanoemulsion as tracer for atherosclerosis MPI and MRI imaging

PURPOSE

For early atherosclerosis imaging, magnetic oil-in-water nanoemulsion (NE) decorated with atheroma specific monoclonal antibody was designed for Magnetic Particle Imaging (MPI) and Magnetic Resonance Imaging (MRI). MPI is an emerging technique based on direct mapping of superparamagnetic nanoparticles which may advantageously complement MRI.

METHODS

NE oily droplets were loaded with superparamagnetic iron oxide nanoparticles of 7, 11 and 18nm and biofunctionalized with atheroma specific scFv-Fc TEG4-2C antibody.

RESULTS

Inclusion of nanoparticles inside NE did not change the hydrodynamic diameter of the oil droplets, close to 180nm, nor the polydispersity. The droplets were negatively charged (ζ=-30mV). In vitro MPI signal was assessed by Magnetic Particle Spectroscopy (MPS). NE displayed MRI and MPS signals confirming its potential as new contrast agent. NE MPS signal increase with NPs size close to the gold standard (Resovist). In MRI, NE displayed R₂* transversal relaxivity of 45.45, 96.04 and 218.81mM^-1s^-1 for 7, 11 and 18nm respectively. NE selectively bind atheroma plaque both in vitro and ex vivo in animal models of atherosclerosis.

CONCLUSION

Magnetic NE showed reasonable MRI/MPS signals and a significant labelling of the atheroma plaque. These preliminary results support that NE platform could selectively image atherosclerosis.

Carbamate-Based Bolaamphiphile as Low-Molecular-Weight Hydrogelators

A new bolaamphiphile analog featuring carbamate moieties was synthesized in six steps starting from thymidine. The amphiphile structure exhibits nucleoside-sugar polar heads attached to a hydrophobic spacer via carbamate (urethane) functions. This molecular structure, which possesses additional H-bonding capabilities, induces the stabilization of low-molecular-weight gels (LMWGs) in water. The rheological studies revealed that the new bolaamphiphile 7 stabilizes thixotropic hydrogels with a high elastic modulus (G′ > 50 kPa).

Determination of surfactant bio-sourced origin by isotope-ratio mass spectrometry

RATIONALE

To develop more eco-friendly laundry detergents, renewable surfactants synthesized from vegetal sources are increasingly being used. In a more stringent regulation context, the determination of bio-sourced surfactant origin thus appears essential to assess the claims of detergent manufacturers. Radiocarbon determination, the standard method for the analysis of bio-sourced materials, is an expensive technique, so there is a need for a cheaper method.

METHODS

Here, the use of an elemental analyzer linked to isotope-ratio mass spectrometry (EA/IRMS) is evaluated as an alternative approach to the official method. The δ(18) O, δ(13) C and δ(2) H isotope-ratio values were determined to investigate the bio-sourced origin of surfactant raw materials and mixtures.

RESULTS

A sample library of 26 commercial surfactants representative of detergent raw materials was first analyzed by EA/IRMS. The δ(18) O, δ(13) C and δ(2) H values allowed discrimination of synthetic and bio-sourced surfactants. Moreover, in this latter group, C4 plant-derived surfactants were distinguished by their δ(13) C values. Binary and ternary mixtures made of synthetic and bio-sourced surfactants were also analyzed and indicated a linear relationship between mixture isotope-ratio values and surfactant proportions.

CONCLUSIONS

IRMS represents a viable alternative to radiocarbon determination for the evaluation of surfactant bio-sourced origin. It is a faster and cheaper technique, allowing discrimination of petroleum- and biomass-derived surfactants and identification of their carbon sources (C4 or C3 plants).

Identification and absolute quantification of enzymes in laundry detergents by liquid chromatography tandem mass spectrometry

In a stricter legislative context, greener detergent formulations are developed. In this way, synthetic surfactants are frequently replaced by bio-sourced surfactants and/or used at lower concentrations in combination with enzymes. In this paper, a LC-MS/MS method was developed for the identification and quantification of enzymes in laundry detergents. Prior to the LC-MS/MS analyses, a specific sample preparation protocol was developed due to matrix complexity (high surfactant percentages). Then for each enzyme family mainly used in detergent formulations (protease, amylase, cellulase, and lipase), specific peptides were identified on a high resolution platform. A LC-MS/MS method was then developed in selected reaction monitoring (SRM) MS mode for the light and corresponding heavy peptides. The method was linear on the peptide concentration ranges 25-1000 ng/mL for protease, lipase, and cellulase; 50-1000 ng/mL for amylase; and 5-1000 ng/mL for cellulase in both water and laundry detergent matrices. The application of the developed analytical strategy to real commercial laundry detergents enabled enzyme identification and absolute quantification. For the first time, identification and absolute quantification of enzymes in laundry detergent was realized by LC-MS/MS in a single run. Graphical Abstract Identification and quantification of enzymes by LC-MS/MS.

Preliminary pharmaceutical development of antimalarial-antibiotic cotherapy as a pre-referral paediatric treatment of fever in malaria endemic areas

Artemether (AM) plus azithromycin (AZ) rectal co-formulations were studied to provide pre-referral treatment for children with severe febrile illnesses in malaria-endemic areas. The target profile required that such product should be cheap, easy to administer by non-medically qualified persons, rapidly effective against both malaria and bacterial infections. Analytical and pharmacotechnical development, followed by in vitro and in vivo evaluation, were conducted for various AMAZ coformulations. Of the formulations tested, stability was highest for dry solid forms and bioavailability for hard gelatin capsules; AM release from AMAZ rectodispersible tablet was suboptimal due to a modification of its micro-crystalline structure.

Screening paediatric rectal forms of azithromycin as an alternative to oral or injectable treatment

The aim of this study was to identify a candidate formulation for further development of a home or near-home administrable paediatric rectal form of a broad-spectrum antibiotic - specially intended for (emergency) use in tropical rural settings, in particular for children who cannot take medications orally and far from health facilities where injectable treatments can be given. Azithromycin, a broad-spectrum macrolide used orally or intravenously for the treatment of respiratory tract, skin and soft tissue infections, was selected because of its pharmacokinetic and therapeutic properties. Azithromycin in vitro solubility and stability in physiologically relevant conditions were studied. Various pharmaceutical forms, i.e. rectal suspension, two different rectal gels, polyethylene glycol (PEG) suppository and hard gelatin capsule (HGC) were assessed for in vitro dissolution and in vivo bioavailability in the rabbit. Azithromycin PEG suppository appears to be a promising candidate.

Development of NIRS method for quality control of drug combination artesunate-azithromycin for the treatment of severe malaria

Near infrared spectroscopy (NIRS) methods were developed for the determination of analytical content of an antimalarial-antibiotic (artesunate and azithromycin) co-formulation in hard gelatin capsule (HGC). The NIRS consists of pre-processing treatment of spectra (raw spectra and first-derivation of two spectral zones), a unique principal component analysis model to ensure the specificity and then two partial least-squares regression models for the determination content of each active pharmaceutical ingredient. The NIRS methods were developed and validated with no reference method, since the manufacturing process of HGC is basically mixed excipients with active pharmaceutical ingredients. The accuracy profiles showed β-expectation tolerance limits within the acceptance limits (±5%). The analytical control approach performed by reversed phase (HPLC) required two different methods involving two different preparation and chromatographic methods. NIRS offers advantages in terms of lower costs of equipment and procedures, time saving, environmentally friendly.

Endovascular treatment of descending aortic dissection (type B): short- and medium-term results

BACKGROUND

Optimal treatment of type B dissections is open to debate. The use of endoprostheses is an option that requires evaluation.

AIM

To report our experience with endoprostheses in type B aortic dissections.

METHODS

We report our short- and medium-term results with covered prostheses for the treatment of acute (n=7) and chronic (n=28) type B aortic dissections. The criteria used to indicate treatment were the same as those usually used for surgery: acute complications or dilated aneurysm. Cover of the main intimal tear was obtained in all cases with an improvement in symptoms in patients with acute dissections.

RESULTS

Early mortality was 14.3% (five patients), linked in three cases to the occurrence of a retrograde dissection of the ascending aorta. No neurological complications were observed. Four patients required an additional endovascular and/or surgical procedure. On early control scans, complete thrombosis of the false lumen at the thoracic level was observed in 40% of cases, partial thrombosis in 42.8% and an absence of thrombosis in 11.4%. After a mean follow-up of 20.8 months, one patient died of a pneumopathy. No secondary aneurysm expansion was noted at the thoracic stage whereas three patients presented with dilation of the abdominal aorta.

CONCLUSION

The results of treatment of type B dissections with covered endoprostheses are encouraging. However, the morbimortality associated with treatment and the uncertainty of long-term results do not allow the use of this therapeutic option outside the criteria usually recognized to indicate surgery.