Design, Principle and Application of Self-Assembled Nanobiomaterials in Biology and Medicine

Design, Principle and Application of Self-Assembled Nanobiomaterials in Biology and Medicine discusses recent advances in science and technology using nanoscale units that show the novel concept of combining nanotechnology with various research disciplines within both the biomedical and medicine fields. Self-assembly of molecules, macromolecules, and polymers is a fascinating strategy for the construction of various desired nanofabrication in chemistry, biology, and medicine for advanced applications. It has a number of advantages: (1) It is involving atomic-level modification of molecular structure using bond formation advanced techniques of synthetic chemistry. (2) It draws from the enormous wealth of examples in biology for the development of complex, functional structures. (3) It can incorporate biological structures directly as components in the final systems. (4) It requires that the target self-assembled structures be thermodynamically most stable with relatively defect-free and self-healing. In this book, we cover the various emerging self-assembled nanostructured objects including molecular machines, nano-cars molecular rotors, nanoparticles, nanosheets, nanotubes, nanowires, nano-flakes, nano-cubes, nano-disks, nanorings, DNA origami, transmembrane channels, and vesicles. These self-assembled materials are used for sensing, drug delivery, molecular recognition, tissue engineering energy generation, and molecular tuning.

• Provides a basic understanding of how to design, and implement various self-assembled nanobiomaterials
• Covers principles implemented in the constructions of novel nanostructured materials
• Offers many applications of self-assemblies in fluorescent biological labels, drug and gene delivery, bio-detection of pathogens, detection of proteins, probing of DNA structure, tissue engineering, and many more

• Language: English
• Publisher: Academic Press
• Release date: Aug 4, 2022
• ISBN: 9780323909853

Book preview

Chapter 1

An introduction of self-assembled nanobiomaterials and their applications

Kriti Srivastava¹, Nidhi Verma¹, Vijai Singh² and Alok Pandya³*,    ¹Department of Bioengineering and Biotechnology, Institute of Advanced Research, Gandhinagar, Gujarat, India,    ²Department of Biosciences, School of Science, Indrashil University, Rajpur, Mehsana, Gujarat, India,    ³Department of Biotechnology and Bioengineering, Institute of Advanced Research, Gandhinagar, Gujarat, India*, Corresponding author.

Abstract

Self-assembled nanobiomaterials have emerged as low-cost and scale-up techniques due to the association of individual units of material into highly ordered structures and patterns, which are suitable for a variety of applications. It has great potential in biomedical applications due to the properties which make them ideal for interaction with biological systems. The usage of biofunctionalized self-assembling nanomaterials has proved their potential to improve therapeutics for a wide range of treatments such as cancer, osteoporosis, and some organ damages. This chapter discusses the fundamental of self-assembled nanobiomaterials and their biomedical and therapeutic applications.

Keywords

Self-assembly; nanobiomaterials; interaction; biomedical applications

1.1 Introduction

Self-assembly is ubiquitous in nature starting from microscopic to macroscopic levels. The self-assembly process in nanobiomaterials takes place when individual units of material come together to form highly ordered molecular structures based on specific local interactions among the organic and inorganic building blocks which are then assembled without the application of any external force. The process conveys distinctive properties to the inorganic and organic structures obtained through noncovalent bonding. Self-assembled nanobiomaterials are derived from noncovalently bonded structures resulting in self-assemblies with well-organized nanostructures from biomaterials [1].

There are two methods of self-assembly of biomolecules to form a nanobiomaterial, that is, based on internal interactions and external stimulations. Internal interactions occur through hydrogen bonds, electrostatic, hydrophobic, and π–π interactions. Additionally, biomolecular-specific interaction-based self-assembly is through DNA base pairing, ligand–receptor binding, antigen–antibody binding, and biomolecule–polymer conjugates. The process for spatial and temporal self-assembly of molecular structures, monolayers, amphiphilic fibers, and a few nanomaterials is achieved under controlled kinetic and thermodynamic conditions. Self-assembly by external stimulation is further classified as static or dynamic, based on the thermodynamic condition set up requirements [2]. In static conditions, the self-assembled nanomaterial is formed when the reduction in free energy is observed as equilibrium is approached by the system. The obtained static structured molecules’ activity and structure cannot be changed any further to perform varied functions by changing the external parameters. Structures resulting from Dynamic self-assembly can change their structures and functions later, confining the thermodynamic equilibrium [3].

The advantages of using self-assembled nanobiomaterials are their unique molecular properties, adjustable functions, and ordered structures. These advantages have been robustly exploited for the applications of self-assembled nanomaterials for biomedical and therapeutic applications. The preference of self-assembled nanobiomaterials like peptides, chitosan, and hydrogels for their use in biological systems is mainly due to their lower toxicity levels in a mammalian cell, effective antimicrobial activity, ability to functionalized for specific reactivity/detection, and stability.

1.2 Application of self-assembled nanobiomaterials

Self-assembled nanobiomaterials have been widely researched in a wide variety of applications in the field of nanotechnology, imaging techniques, biosensors, nanomedicines, drug delivery, and biomedical devices, and have marked their great potential. Self-assembled molecules and structures are either biomimetically derived or novel designed. Both of them have feasible application potential as nanomaterials in regenerative medicine [4–6], cancer research [7,8], three-dimensional (3-D) cell culture [9,10], drug and gene delivery [11,12], and antimicrobial films [13]. Additionally, several developments have been made in the fabrication of bone grafts, tissue engineering, and wound dressing nanobiomaterials using self-assembled micelles [14].

The use of self-assembled nanobiomaterials in drug delivery and nanobiomedicine facilitates the diagnosis and treatment of certain diseases owing to its numerous advantages(Vásquez [15–17]), like improved cellular uptake and bioavailability of poorly soluble drugs, due to the reduced size and improved geometry [18,19]. Further, drugs encapsulated by nanobiomaterials have increased circulation time, subsequently improved biodistribution and pharmacodynamics in the biological systems. Moreover, functionalization of nanomaterials by biologically active and responsive molecules can exhibit different properties, like specific organ/tissue targeting or the stimulus-response to the changes in environmental conditions, further facilitating the reduction of drug accumulation unused drug and effective dosage by limiting the drug administration when the specific target is reached [20–22]. The control over physiochemical properties of nanogels, including the nanosize, stability, ability for functionalization of the surface making it suitable for bioconjugation procedures, and biodegradability, has aided in their preference expansion in the range of drug delivery system applications adding to the variety of drugs and pharmacokinetic profiles suitable for the treatment of diseases [23]. Additionally, the use of nanomaterials for drug delivery vehicles in cancer treatments is gaining increasing attention for research due to their passive action on target tumor tissues through improved permeability and lesser side-effects of the drug compared to traditional chemotherapeutic methods. When compared to other drug delivery vehicles, nanohydrogels have been proven in research to be more effective and safer due to their size and function-based unique properties, such as their high stability biological systems. Because of the cross-linked structure of nanohydrogels, they possess excellent drug loading capacity, high hydrophilicity, and improved biocompatibility [24].

In molecular self-assembled materials, the amphiphilic peptides are distinguished by their structure comprising of a hydrophobic tail and hydrophilic head as their key building blocks. Here, using a hydrophobic interaction as the driving force, the self-assembly of amphiphilic peptides is achieved in an aqueous solution. They have great potential applications as nanobiomaterials [5]. The different types of self-assembled nanomaterials are based on polymer, lipids, and polymer-lipid hybrids. The self-assembly of amphiphiles like micelles, vesicles, and hydrogels into nanostructures is a result of various physical interactions. The commonly used self-assembled nanobiomaterials include chitosan, peptides, and a few hydrogels.

Natural polymers such as chitosan, alginate, polyesters, and polyanhydrides are a few natural biomaterials that can provide the opportunity for physiochemical improvements for immobilization of specific drugs and biochemical ligands [25]. Nanobiomaterial based delivery systems are observed for stimulus responsiveness to release drugs based changes in pH, light, frequency, redox potential, temperature, catalyst, and acidic/basic environment have been widely investigated for improvements in target delivery [26]. Chitosan is used for certain biomedical and pharmaceutical applications, including drug/gene/vaccine delivery, damaged tissue/organ healing, and healing of wounds [27–29]. It is widely used as it is a natural cationic polysaccharide having a hydroxyl and amino group. And is capable to form stable complexes with negative chemical compounds. Chitosan is a weak polybase with charge density variation in the pH range of 6–6.5. This further gives an additional advantage of pH-responsiveness, which is beneficial for various therapeutics as the suitable range for biological applications is between pH 6 and 6.5. Chitosan is preferred for specific drug delivery due to many advantages it possesses like biocompatibility, the ability to encapsulate the unstable drugs to protect them from the acidic environment in the gut and immune responses in blood, their ability in adherence to inner mucosal lining tissues helps in the uptake of drugs at the target sites, easier linkage with biological macromolecules like DNA [30–32]. It has been studied that chitosan’s association with cells in epithelia and mucus gives an advantage of improved permeability in the tight cellular junctions helping in the targeted drug delivery systems. Some studies done on nanodrug delivery systems for disease treatments have used chitosan-based nanomaterials [21,33]. The properties of chitosan are also preferable for developing a carrier system for proteins and peptides for therapeutics. Chitosan nanocarriers have also been researched as oral delivery systems, it works by encapsulating the orally administered drug. It protects the drug from the strongly acidic environment and enzymatic deactivation in the stomach and helps overcome physical barriers such as the mucosal layer, cellular junctions of epithelial cells, and enzymatic barriers. Molecules for therapeutics including the proteins, genes, hydrophobic complex drug molecules, and polysaccharides, can be linked to chitosan-based nanocarrier systems, for their delivery into the small intestine and further entering into the systemic circulation. In many cases, nanocarriers based out of chitosan have helped with improving in-vivo drug accessibility, for enhanced treatment effect for a longer period of time [34]. Chitosan is a natural biopolymer with antibacterial activity, such microbial growth inhibitory effects are because of charge-based interaction between the bacterial cell membrane which is negatively charged and positively charged chitosan [35]. Several studies and research have reported the successful and effective development of antibacterial systems from chitosan-based nanoparticles [36–39]. Further work has been done to evaluate the effectiveness of natural biopolymers, alginate, and chitosan together, for the elaboration of their usage in nanocapsules with tuneable antibacterial properties [13].

1.2.1 Application of self-assembled nanobiomaterials in the biological environment

The process of self-assembly plays a crucial role in the biological environment for the emergence of macromolecular structures such as DNA, proteins, and lipids to form a membrane system, which together forms the central dogma of molecular biology. The functions of these biomacromolecules in bioprocesses are storage and transfer of signals and information through DNA and RNA, compartmental division for membranes, biochemical catalysis, and communication of various signals through proteins. Formation of various nanostructures by self-assembly of peptide structures such as amphiphilic, cyclic, and hybrid peptides, is achieved by a stable balance of noncovalent bonds through weak interactions. Amphiphilic peptides have shown great potential to support the growth of the cell populations when used as tissue scaffolds and 3D structures to mimic extracellular matrix. These nanomaterials have successfully supported cell proliferation, due to their compatibility with plasma membranes [40]. Peptides like Glu6 and Asp6 can attach to the bone structures via hydroxyapatite (HA) interactions, which are utilized for specific imaging techniques [41]. This specific attachment of the peptide aids specific imaging in osteoporosis and bone fractures for efficient therapeutics [42,43]. Significant advancements have also been made in clinical research on nanocomposites made up of HA particles for hard tissue engineering. They are preferred for hard tissue engineering in bones owing to their improved osteoconductivity, osteoinductivity, biodegradability, and high mechanical strengths which makes them perfectly suited for ortho applications. In a recent study, nanocomposites from polycaprolactone-nanohydroxyapatite (PCLnHA) were developed and combined the osteoconductivity and biocompatibility using gelatin which helps reduce the brittleness and promote the attachment to the targeted site [44]. Nanocomposite produced by the combination of HA and gelatin was observed to be supportive to adherence and growth of human osteoblast cells. The properties of nanobiomaterials from nanocomposites with HA have greater application for their effective usage in bone tissue engineering including bone regeneration, cartilage regeneration, bone implants, dental tissue regeneration, and tooth regeneration. Research had shown, a specific muscle-targeting peptide to target a virus through a specific-binding ligand to the muscles for the screening and treatments of heart and skeletal muscle diseases [45]. The peptides that can target other tissues including the kidney [46] and liver [47] have been analyzed and optimized for specific kidney and liver diseases. Few studies have shown, matrix scaffolds developed from self-assembled peptide supports cell differentiation and growth, in addition to that these peptides were able to help and boost various types of cellular attachments [48–50].

Natural antimicrobial sources, including the antimicrobial peptides [51–53], cationic natural-polymers [54,55], naturally derived photothermal/photodynamic molecules [56,57], and a few more molecular structures have been analyzed and functionalized for self-assembly of these key structures with improved antimicrobial properties [24]. Along with directly prohibiting bacterial growth, self-assembled materials with multilayered nanostructures have demonstrated excellent antibiofouling and inhibition of biofilm development property also shows bacterial inhibition effect [58,59]. Other than organic self-assembled nanomaterials, few hybrid inorganic nanomaterials have unique antimicrobial mechanisms with comparatively fewer side effects in biological systems through certain modifications for targeted applications [60].

In another work, a unique property of self-assembly induced by enzymes to prepare supramolecular materials gives the chance of controlling the folding of peptides and self-assembly processes is highlighted [61]. This was further used for imaging and therapeutic in living cells for clinical purposes. The use of self-assembled peptides and protein nanomaterials for drug delivery carriers in chemotherapies and vaccine developments has also been analyzed. These are used for improving the efficiency of photo therapies which are also known as the noninvasive cancer treatment methods [62]. The research suggests that self-assembled nanostructures of peptides and proteins which are suitable for biological applications being biocompatible can be fabricated using certain controls for the specific needs in Photodynamic therapy and Photothermal therapy utilized for cancer treatment. Another research concluded that the rheological properties of a peptide-based hydrogel associated with iron nanoparticles are substantially enhanced by inducing the self-assembly in a magnetic field set-up [63]. The results had shown improvements in the efficiency as contrast agents for magnetic resonance imaging and heat source requirements for magnetic hyperthermia. The obtained data from the research on biological and rheological properties of the hydrogelators have been analyzed for biocompatibility tests for suitable clinical applications.

For anticancer drug delivery systems, research has been done on polyacrylic acid grafted with nanohydrogels from dextran via covalently cross-linked structures along with redox-sensitive crosslinked junctions [64]. The obtained results suggest that the self-assembled nanohydrogel with dextran showed a controlled drug release based on pH and redox conditions, reduction in the toxicity of free doxorubicin which is an anticancer drug while inhibiting the growth of MDA-MB-231 tumors. This work has actively tried to overcome the limitation of single responsiveness to tumor environments with multi responsiveness aiding to lower dosage methods for controlled chemotherapy drug release. In another research work, the use of a self-assembled peptide bridge is employed and evaluated for Caspase-3 detection, which is a cellular marker and key mediator for apoptosis activation by both extrinsic and intrinsic pathways leading to apoptotic cell death [65].

1.2.2 Self-assembled living materials

Self-assembled living materials are currently playing a key role in designing self-assembled biomaterials having strong strength, stability, and structure. Synthetic biology is a new area that can help to design and fine-tune self-assembled nanomaterials for a wide range of applications in biomedical sciences, biotechnology, and nanotechnology. Self-assembled living materials endow high mechanical strength and ability to remodel and regenerate, which normally is absent in synthetic materials. Living functional materials and their synthesis incorporates both inorganic as well as living materials to produce materials for biomanufacturing. It is self-assembling, self-healing, and self-growing and can be manipulated by genetic engineering, or through chemical means and spatial patterning to be employed in a wide range of functions.

In this study, Chen et al. [66] designed a synthetic gene system in Escherichia coli for enabling the formation of biofilms. It resulted in dynamically organized biotic–abiotic materials with high tunability that has been used as template for nanorods, nanowire and semiconductor nanoparticles synthesis. With the aid of the synthetic biology approach towards designer systems, hybrid novel materials can be produced as functional materials having the ability of self-healing, adaptability, and evolution. It is properly organized, distributed, and self-assembled for its biotechnological and biomedical applications. In addition, nanoscale self-assembled living materials were synthesized in E. coli and characterized for their stability and elasticity [67]. Self-assembled materials can be used for micro-scale to large-scale synthesis of structural materials or hybrid devices, and biocatalyst or toxin sequestration [68]. Recent advances in molecular biology and functional genomics are opened a new avenue for the development of novel bioinspired molecular materials by using tools of synthetic biology that can be further extended into more complex biomaterials.

1.3 Conclusion

Due to the association of individual units of material into highly ordered structures and patterns, self-assembled nanobiomaterials have emerged as low-cost and scale-up approaches that are appropriate for a variety of applications. Because of the features that make it perfect for interaction with biological systems, it has a lot of potential in biomedical applications. The use of biofunctionalized self-assembling nanomaterials has demonstrated their ability to improve therapy for a variety of diseases, including cancer, osteoporosis, and organ damage. The fundamentals of self-assembled nanobiomaterials and their biomedical and therapeutic applications are discussed in this chapter.

Acknowledgments

Alok Pandya and Nidhi Verma gratefully acknowledge Gujarat State Biotechnology Mission (GSBTM Project ID: AJJV48) and SHODH: Scheme of Developing High-Quality Research Scholarship (Ref No: 201901440009) for financial support.

References

1. Ulijn RV, Smith AM. Designing peptide based nanomaterials. Chem Soc Rev. 2008;37(4):664–675 https://doi.org/10.1039/b609047h.

2. Grzybowski BA, Wilmer CE, Kim J, Browne KP, Bishop KJM. Self-assembly: from crystals to cells. Soft Matter. 2009;5(6):1110–1128 https://doi.org/10.1039/b819321p.

3. Varga M. Self-assembly of Nanobiomaterials Fabrication and Self-assembly of Nanobiomaterials: Applications of Nanobiomaterials Elsevier Inc 2016; https://doi.org/10.1016/B978-0-323-41533-0.00003-9.

4. Moore AN, Hartgerink JD. Self-assembling multidomain peptide nanofibers for delivery of bioactive molecules and tissue regeneration. Acc Chem Res. 2017;50(4):714–722 https://doi.org/10.1021/acs.accounts.6b00553.

5. Qiu F, Chen Y, Tang C, Zhao X. Amphiphilic peptides as novel nanomaterials: design, self-assembly and application. Int J Nanomed. 2018;13:5003–5022 https://doi.org/10.2147/IJN.S166403.

6. Wan S, Borland S, Richardson SM, Merry CLR, Saiani A, Gough JE. Self-assembling peptide hydrogel for intervertebral disc tissue engineering. Acta Biomater. 2016;46:29–40 https://doi.org/10.1016/j.actbio.2016.09.033.

7. Mi K, Wang G, Liu Z, Feng Z, Huang B, Zhao X. Influence of a self-assembling peptide, RADA16, compared with collagen I and matrigel on the malignant phenotype of human breast-cancer cells in 3D cultures and in vivo. Macromol Biosci. 2009;9(5):437–443 https://doi.org/10.1002/mabi.200800262.

8. Tang C, Shao X, Sun B, Huang W, Zhao X. The effect of self-assembling peptide RADA16-I on the growth of human leukemia cells in vitro and in nude mice. Int J Mol Sci. 2009;10(5):2136–2145 https://doi.org/10.3390/ijms10052136.

9. Hogrebe NJ, Gooch KJ. Direct influence of culture dimensionality on human mesenchymal stem cell differentiation at various matrix stiffnesses using a fibrous self-assembling peptide hydrogel. J Biomed Mater Res A. 2016;104(9):2356–2368 https://doi.org/10.1002/jbm.a.35755.

10. Scott CM, Forster CL, Kokkoli E. Three-dimensional cell entrapment as a function of the weight percent of peptide-amphiphile hydrogels. Langmuir. 2015;31(22):6122–6129 https://doi.org/10.1021/acs.langmuir.5b00196.

11. Liu J, Zhang L, Yang Z, Zhao X. Controlled release of paclitaxel from a self-assembling peptide hydrogel formed in situ and antitumor study in vitro. Int J Nanomed. 2011;6:2143–2153 https://doi.org/10.2147/ijn.s24038.

12. Wu M, Ye Z, Liu Y, Liu B, Zhao X. Release of hydrophobic anticancer drug from a newly designed self-assembling peptide. Mol Biosyst. 2011;7(6):2040–2047 https://doi.org/10.1039/c0mb00271b.

13. Belbekhouche S, Bousserrhine N, Alphonse V, et al. Chitosan based self-assembled nanocapsules as antibacterial agent. Colloids Surf B: Biointerfaces. 2019;181:158–165 https://doi.org/10.1016/j.colsurfb.2019.05.028.

14. Hasirci V, Vrana E, Zorlutuna P, et al. Nanobiomaterials: a review of the existing science and technology, and new approaches. J Biomater Sci Polym Ed. 2006;17(11):1241–1268 https://doi.org/10.1163/156856206778667442.

15. Marcano V, del Jesus RG, Tominaga TT, Khalil NM, Pedroso LS, Mainardes RM. Chitosan functionalized poly (ε-Caprolactone) nanoparticles for amphotericin B delivery. Carbohydr Polym. 2018;202:345–354 https://doi.org/10.1016/j.carbpol.2018.08.142.

16. Hsiao MH, Mu Q, Stephen ZR, Fang C, Zhang M. Hexanoyl-chitosan-PEG copolymer coated iron oxide nanoparticles for hydrophobic drug delivery. ACS Macro Lett. 2015;4(4):403–407 https://doi.org/10.1021/acsmacrolett.5b00091.

17. Bhavsar C, Momin M, Gharat S, Omri A. Functionalized and Graft Copolymers of Chitosan and its Pharmaceutical Applications Expert Opinion on Drug Delivery. Vol. 14 Taylor & Francis 2017; https://doi.org/10.1080/17425247.2017.1241230.

18. Ferji K, Venturini P, Cleymand F, Chassenieux C, Six JL. In situ glyco-nanostructure formulation via photo-polymerization induced self-assembly. Polym Chem. 2018;9(21):2868–2872 https://doi.org/10.1039/c8py00346g.

19. Wang Z, Luo T, Cao A, Sun J, Jia L, Sheng R. Morphology-variable aggregates prepared from cholesterol-containing amphiphilic glycopolymers: their protein recognition/adsorption and drug delivery applications. Nanomaterials. 2018;8 https://doi.org/10.3390/nano8030136.

20. Hoop M, Mushtaq F, Hurter C, Chen XZ, Nelson BJ, Pané S. A smart multifunctional drug delivery nanoplatform for targeting cancer cells. Nanoscale. 2016;8(25):12723–12728 https://doi.org/10.1039/c6nr02228f.

21. Li J, Cai C, Li J, et al. Chitosan-based nanomaterials for drug delivery. Molecules. 2018;23(10):1–26 https://doi.org/10.3390/molecules23102661.

22. Park JH, Saravanakumar G, Kim K, Kwon IC. Targeted delivery of low molecular drugs using chitosan and its derivatives. Adv Drug Deliv Rev. 2010;62(1):28–41