Nanoscale Functional Polymers for Health and Social Welfare

Nanomedicine embraces mostly, though not exclusively, the biomedical application of nanoscale materials for diagnosis and therapy. Due to the unique features of nanoparticles (NPs), including multifunctionality, large surface area, structural diversity, capacity to protect drugs and long circulation time in blood compared to small molecules, among many others, they have emerged as an attractive preference for optimized therapy. Surface biofunctionalziation of NPs also endow them with longer controlled release profiles, biocompatibility and targeting.

Surface biofunctionalization, in fact, is not only of relevance for NPs but also in many other pertinent surfaces, insofar as it allows for the fine-tuning of the hydrophobic/hydrophilic balance, biocompatibility or other additional bioproperties such as anti-bacterial character.

 

To achieve all these objectives, polymers represent the leading biomaterials so far used. They can be designed with a range of architecture, functionalities and appropriate characteristics. In our group we work both with commercial FDA-approved polymers, as well as with novel biopolymers specifically designed for improved performance, as described next:

I. Catechol-based Polymers

Catechol derivatives are widely found in nature taking part in a variety of biological functions, ranging from the aqueous adhesion of marine organisms to the storage of transition metal ions. This has been achieved thanks to their (i) rich redox chemistry and ability to cross-link through complex and irreversible oxidation mechanisms, (ii) excellent chelating properties, and (iii) the diverse modes of interaction of the vicinal hydroxyl groups with all kinds of surfaces of remarkably different chemical and physical natures. In recent years, a growing amount of research efforts have been aimed at mimicking and translating these inherent features into new functional adhesives and coatings with enhanced properties.

So far, our main goal has been to gain a better understanding of catechol-based interfaces and to use them to improve our ability to effectively control critical performance parameters such as wettability, colloidal stability and controlled release. We are currently focused on the development of new catechol-based materials to be used as a) bioadhesives, and b) functional coatings for nanostructures intended for biomedical applications. Emphasis is laid on the design of catecholic monomers that allow the incorporation of several functionalities within a single, bio-compatible polymeric framework in a tunable fashion, by means of straightforward and cost-effective synthetic routes. One of the main goals is to develop nanosystems able to cross the BBB, and thus target the Central Nervous System directly.

 

Selected references:
 ACS applied materials & interfaces 2017, 9 (51), 44641-44648
Advanced Functional Materials 2016, 26 (16), 2745-2755
ACS applied materials & interfaces 2014, 6 (20), 17616-17625
Small 2014, 10 (8), 1594-1602
Chemical Communications 2014, 50 (83), 12548-12551
Advanced Materials 2013, 25 (14), 2066-2070
Advanced Materials 2013, 25 (5), 653-701

II. Engineering Polymers for Optimal Micro-/Nanoencapsulation

 The main objective is to develop nanosystems for the encapsulation of active species and their selective release in the site of action. The current research is focused on FDA approved polymers (PLGA, PLA, polyCaprolactone, Eudargit®) for the encapsulation of specific drugs (polymers, enzymes, nutraceuticals) for the treatment of Neurodegenerative diseases.

Selected references:
Chemistry-A European Journal 2017, 23 (12), 2753-2758
Controlled Release 2018, submitted

III. Coordination Polymers

 Miniaturization of coordination complexes and polymers to the nanoscale (nanoparticles or structured surfaces) represents a unique opportunity to amass a novel class of highly customizable functional materials that marry the rich diversity, chemistry and properties of coordination synthesis to the advantages of nanomaterials. Accordingly, micro-/nanoscale metal-organic particles (including metal-organic frameworks) have already shown their efficacy as encapsulation carriers, drug delivery, or theranostics platforms. In this scenario, Nanosfun research group has focused on the design, synthesis, physicochemical characterization, and in vitro/in vivo assays for the development of new nanoconstructs based on organic polymers and metal-organic coordination polymers with application in specific diseases. In this regard, the main scientific objectives of Nanosfun are:

  1. Understand the formation mechanism of polymeric NPs, to tune their structure and composition or to facilitate the conversion into novel multifunctional nanostructures.
  2. Having control over their surface functionality or to master their properties and morphologies with enhanced properties at the nanoscale. One of the main objectives is to obtain nanostructures able to cross physiological barriers, especially BBB.
  3. The group is also exploring the boundaries of the metal-organic polymeric materials by exploring the synthesis and multifunctional properties of these new nanoplatforms, and their application in drug delivery or bioimaging field.  
  4. Design of multifunctional nanoparticles for an specific disease though direct collaboration with hospitals, medical centers and research institutes. Specific targets are cancer, neurodegenerative diseases or HIV, among others.

Selected references:
 Expert opinion on drug delivery 2017, 14 (6), 783-796
Dalton Transactions 2016, 45 (28), 11233-11255
 Chemistry-A European Journal 2015, 21, 10094 – 10099
Chemistry-A European Journal 2014, 20 (47), 15443-15450
Chemical Communications 2014, 50 (93), 14570-14572
Chemistry-A European Journal 2013, 19 (51), 17508-17516
Coordination Chemistry Reviews 2013, 257 (19-20), 2839-2847
Chemical communications 2009, 46 (26), 4737-4739
Angewandte Chemie International Edition 2009, 48 (13), 2325-2329