Biomedical Applications of Perovskites: The Era of Bio-Piezoelectric Systems

Perovskite (Calcium titanium oxide), which was discovered in 1839 by Perovski, a Russian mineralogist, has some favorable photophysical characteristics that enable perovskite and its nanocrystals to be used in the field of biomedical research. Presently, perovskites are being explored for various medical applications, including X-ray detection and imaging, cancer treatment, orthopedic implants and as antimicrobial agents. Advancements in nanocrystal research allowed the exploration of perovskites for their antibacterial, antifungal and antiviral activity against Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2). The antibacterial activity of several perovskite nanoparticles was explored, and to mention a few, Cesium lead bromide and zinc oxide perovskite nanoparticles showed activity against Escherichia coli, while Lanthanum potassium ferrate and silver-based perovskites against Staphylococcus aureus and Pseudomonas aeruginosa. This chapter will review the potential research studies that explored the anti-microbial activity of perovskites and their nanoparticles against bacteria, viruses, fungi and other microorganisms and provide insight into the mechanisms by which these particles exert antimicrobial action. Further, this chapter will discuss the potential biomedical applications of the antimicrobial activity of perovskites.

Perovskite structures have strong piezoelectric properties, making them suitable for a wide range of applications such as sensors, energy harvesting devices and actuators. The chapter examines numerous synthesis procedures, including coprecipitation, hydrothermal, solid-state reaction, the Pechini process, sol-gel autocombustion, low temperature, and pulsed-laser decomposition. Each technique's principles, benefits, limits, and special concerns are given, along with instances of successful perovskite synthesis. Furthermore, the chapter examines current advances and upcoming trends in the area, offering insights into the future direction of piezoelectric perovskite synthesis.

Perovskite (Calcium titanium oxide)was discovered in 1839 by Alekseevich Perovski, a Russian mineralogist. Perovskites are materials with the same structure as calcium titanium oxide (CaTiO3 ) mineral or you can say that all the materials with the same structure as CaTiO3 are perovskites. The basic structure of perovskite is ABX3 , where the A-site is generally occupied by large twelve coordinated cations and B by smaller, octahedrally coordinated cations, and X is a common anion, for instance, Oxygen. A cation is divalent and B is tetravalent cation. Tilting of BO6 octahedra through B-O-B linkage results in rhombohedral, orthorhombic and tetragonal structures. The structure of perovskites can be modified by doping and altering synthesis techniques, such as by changing pH value, calcination temperature, and calefactive velocity. Perovskite materials have a wide range of applications in different fields, such as solar cells, photodetectors, sensors, water purification, etc. 

Perovskite materials, with their unique properties and distinct crystal structure, have proven themselves as one of the most promising materials for various advanced technological applications. The exploration of ferroelectric and piezoelectric materials has gained significant attention in the field of condensed matter physics and materials science, and consequently, it is giving an edge to nanoengineered materials. This book chapter presents a comprehensive exploration of the ferroelectric and piezoelectric response exhibited by perovskite materials based on their crystal structure and other governing properties. The chapter begins with an introduction to perovskite structures, highlighting their crystallographic arrangement and the underlying principles governing their ferroelectric and piezoelectric behaviors. Finally, the chapter explores the diverse technological applications enabled by the unique ferroelectric and piezoelectric properties of perovskites. It discusses their utilization in sensors, actuators, energy harvesting devices, memory storage, and other emerging fields. The chapter concludes with an outlook on future directions and challenges in the field. The extensive study of the ferroelectric and piezoelectric response of perovskites will serve as a valuable resource for researchers, engineers, and students seeking to understand the underlying principles, characterization techniques, and potential applications of perovskite material.

Perovskite materials are well-known for their remarkable thermal, optoelectronic, and magnetic capabilities. This chapter examines current advances in the study of biological applications involving perovskites. This chapter looks at how organic-inorganic hybrid perovskites can be used for X-ray detection and imaging. This can be achieved by switching to Cs+ -cations or MA+/Cs+ alloyed motifs, which not only widen the band gaps but also enhance the structural stability of perovskite materials. The future research direction should focus on fabricating large-area and thick 2D perovskite absorbers on thin-film transistor arrays through compatible printing (polycrystalline) and self-assembled (monocrystalline) methods to achieve X-ray detectors and imagers with high sensitivities and responsivities. The detailed material phases of La0.7Sr0.3Mn0.98Ti0.02O3 perovskite nanoparticles have not been unambiguously elucidated due to inaccurate relative compositions of metal cations. Therefore, insightful structural analysis of the material is needed for confirmation of the magnetically thermally active phase. In the case of perovskite La2NiMnO6 nanoparticles, their ability to desorb BSA protein molecules has not been studied, which is required to fully comprehend the binding/detachment dynamics of enzyme reactions. Finally, the future research direction of CaTiO3 -based composites is to further understand their structure-property relationships under more complicated chemical environments with variations in temperature, pH, and pressure, given their promising biocompatibility and cytotoxicity. 

Perovskite inorganic perovskite-type oxides are intriguing nanomaterials with numerous uses in electrochemical sensing, fuel cells, and catalysis. Because they are catalytic when employed as electrode modifiers, perovskites made at the nanoscale have recently attracted a lot of attention. These oxides have stronger catalytic activity than many compounds made of transition metals and even some oxides of precious metals. They display desirable physical and chemical properties like electronic conductivity, electrical activity, oxygen content variations, mobility of oxide ions through the crystal lattice, thermal and chemical stability, and super-magnetic, photocatalytic, thermoelectric, and dielectric properties. In oxygen reduction and hydrogen evolution events, nano-perovskites have been used as catalysts because they have strong electrocatalytic activity, low activation energy, and strong electron transfer kinetics. Additionally, some perovskites provide good prospects for the production of efficient anodic catalysts with high catalytic performance for direct fuel cells. They can improve the performance of the catalytic process in terms of selectivity, sensitivity, exceptional long-term stability, good repeatability, and interference-fighting capacity. 

This chapter investigates how perovskite materials affect animal cell responsiveness and sheds light on possible biomedical uses. Perovskites are interesting prospects for a variety of biomedical applications because of their distinctive physical and chemical characteristics. The discussion of perovskites' interactions with cells includes their uptake and internalization by cells, as well as how cells react to scaffolds and substrates made of perovskites. The chapter also explores how the composition, structure, surface chemistry, and stability of perovskites affect cell behavior and response. Examining signaling cascades and intracellular destiny, mechanistic insights into perovskite-cell interactions are considered. The chapter concludes by examining existing and potential uses and risks involved with perovskite materials on tissues and regeneration of cells, identifying difficulties and pointing the way forward for further study. This chapter offers insightful information on how perovskites affect cell responsiveness, opening the door for the creation of ground-breaking perovskite-based biomedical solutions.

Perovskites can be used to develop new drugs and materials to combat antimicrobial resistance. These materials are useful in the field of biomedicine due to their chemical properties. They can also be used in the treatment of cancer and other diseases. Researchers are investigating the fate and behavior of perovskites in the environment to assess any potential risks and develop appropriate disposal and recycling methods. Perovskite materials have emerged as a new class of antimicrobial agents with potential applications in various fields. Their unique crystal structure, synthesis methods, and mechanisms of antimicrobial activity make them promising alternatives or add-on agents to conventional antimicrobial agents. The antimicrobial activity of perovskites presents new opportunities for addressing the challenges posed by antimicrobial resistance. Continued research and development efforts are necessary to optimize perovskite synthesis, enhance their stability, evaluate their toxicity, and explore their practical applications in healthcare, water purification, food preservation, textiles, and environmental remediation. In summary, the antimicrobial activity of perovskite materials holds great promise in combating infectious diseases and addressing the growing threat of antimicrobial resistance. Continued research and technological advancements in this field can contribute to the development of effective and sustainable antimicrobial strategies.

 Perovskite materials are becoming more popular in biomedical applications, notably bone tissue engineering and regenerative medicine. Their distinct physical features, such as high dielectric constant, ambipolar charge transfer, and ferroelectricity, make them ideal for bone regeneration. Perovskite-based scaffolds may replicate bone tissue's extracellular matrix and encourage cell behavior, hence aiding bone tissue regeneration. These materials have the potential to completely transform bone defect and injury therapy in regenerative medicine. However, issues like degradation, scalability, toxicity, device interaction, and cost must be solved before they can be widely used. To overcome these challenges, it is necessary to improve stability, scalability, and repeatability, reduce toxicity, achieve device compatibility, reduce manufacturing costs, and develop standardized testing and safety norms. To completely understand the biocompatibility and long-term effectiveness of perovskite materials in bone treatment, further studies and development are required. Despite these difficulties, perovskite materials offer promise in the treatment of bone abnormalities and fractures by acting as scaffolds for bone regeneration, medication delivery vehicles, and imaging agents. Overall, perovskite materials have the potential to improve bone regeneration and advance musculoskeletal disease therapies.

Similar to other transition metal oxides with the same formula, ABO3 , perovskite has a cubic or nearly cubic structure. According to where the electron and energy band gaps are located, perovskite materials can be divided into three categories, with the third combining the first two. The first type has localized electrons while the second type has delocalized energy-band states, and the third type is a transition between the abovementioned two types. There are several types of perovskites, including Layered Perovskite, Perovskite ABO3 , Double Perovskite, and Triple Perovskite. The important characteristics relevant to oxide and oxide-like perovskite crystals are insulator-metal transition, ionic conduction characteristics, dielectric, superconducting, alteration of solid-state phenomenon, and metallic properties. Recently, a number of perovskite applications, including those for random access memories, actuators, tunable microwave displays, piezoelectric devices, transducers, wireless communications, sensors, and capacitors, have been investigated. Electrochromic, photochromic, and filtering devices all demonstrate perovskite's great utility in surface acoustic wave signal processing. 

Regeneration of damaged bone tissue can be accomplished by mimicking the extracellular matrix (ECM) by generating porous topographic substrates. The process of bone tissue regeneration is supported by incorporating natural proteins and growth factors. The scaffolds developed for bone tissue regeneration support bone cell growth and induce bone-forming cells by using natural proteins and growth factors. Limitations associated with the referred approaches are improper scaffold stability, insufficient cell adhesion, proliferation, differentiation and mineralization with less expression of growth factor. Therefore, the use of engineered nanoparticles has been rapidly increasing in bone tissue engineering applications. The electrospray technique that produces nanomaterials has an advantage over other conventional methods as it generates particle sizes in the micro/nanoscale range. The size and charge of the particles are controlled by regulating the flow rate and electric voltage of the polymer solution. The unique properties of nanoparticles are the large surface area to volume ratio, small size and higher reactivity, making them a suitable substrate to be used in the field of biomedical engineering. These nanomaterials are extensively used for drug delivery as therapeutic agents, mimicking cellular components of extracellular matrix and restoring and improving the functions of damaged organs. The controlled and sustained release of encapsulated drugs, proteins, vaccines, growth factors, cells and nucleotides from nanoparticles has been well-established in nanomedicine. The present chapter provides insights into the preparation of nanoparticles by electrospraying and illustrates the use of nanoparticles in drug delivery for the purpose of bone tissue engineering.

The incidence of dental problems is increasing owing to the modern lifestyle, sticky food and poor dental hygiene. Root canal treatment is one of the most common clinical practices in conservative dentistry. Despite the availability of various GIC materials, strength and durability remain the most common concerns. The mechanical properties of tooth filling material are compromised due to disturbances in glass and liquid composition or powder/liquid ratio, glass particle size, pretreatment, manual mixing. The intrinsic porosity is also influenced by reduced viscosity or compared with proportionate liquid ratio, resulting in increased porosity in the cement structure. The availability of nanoparticles, specifically that of perovskites, opens a new dimension. Since they are relatively smaller in size, they can offer stronger binding and cementing properties.

Neurodegenerative disease (ND) is a progressive neurological condition that leads to damage to the neuronal connection essential for various sensory, motor and cognitive functions. Neurotrauma (NT) is an external injury to the brain or spinal cord. The incidence and prevalence of ND and NT are alarmingly increasing owing to several factors such as food intake, modern lifestyle, increased life expectancy and several other comorbid conditions. The identification of novel materials that can cross the BBB and delay or deny the onset and progress of neuropathophysiology of ND is essential. Perovskite, a nanomaterial with some specific characteristics such as semiconducting, photoemitting, photothermal, ferromagnetic and cations exchange properties, fosters the need for further exploration in the treatment of NDs and neurotrauma (NT). With subsequent research, the toxic side effects of perovskite are also minimized with the synthesis of lead-free perovskite. Various computational models, such as neuro-morphic networking, are used to explore the ability of perovskites to facilitate neural synapsis in NDs and NT. Potential identification of the novel pathway of ND directs in modifying the strategic intervention of ND. Initial findings regarding the application of perovskites in the treatment of NDs and NT have shown promising outcomes that need further exploration.

 Fouling is a significant issue in wastewater treatment processes, leading to reduced efficiency and increased operational costs. Perovskite materials have emerged as a promising solution for antifouling treatment in wastewater systems due to their unique properties and versatile applications. This book chapter provides an overview of the recent advancements in perovskite-based antifouling strategies and highlights the challenges that need to be addressed for their practical implementation. Traditional antifouling strategies often involve the use of toxic chemicals that have detrimental effects on marine ecosystems. Therefore, there is a growing need for environmentally friendly and sustainable alternatives. In recent years, perovskite materials have emerged as a promising candidate for antifouling treatments due to their unique physicochemical properties. The use of perovskite materials in antifouling applications primarily relies on two approaches: photodynamic and photocatalytic mechanisms. Photodynamic antifouling involves the generation of reactive oxygen species (ROS) upon exposure to light, which can effectively disrupt and prevent the attachment and growth of fouling organisms. On the other hand, photocatalytic antifouling employs perovskite materials as catalysts to trigger chemical reactions that degrade fouling organisms or their adhesion mechanisms. By harnessing their unique properties, perovskite-based coatings have demonstrated significant antifouling capabilities. Continued research and development efforts are necessary to overcome technical challenges and evaluate the long-term effectiveness and environmental implications, ultimately paving the way for the practical application of perovskite-based antifouling treatments in diverse marine industries.

Due to its one-of-a-kind qualities, such as high sensitivity, cheap cost, and simplicity of manufacture, perovskite sensors have shown a lot of potential in the field of monitoring a person's physical health. This is especially true in light of recent research. This is due to the fact that producing perovskite sensors is a straightforward and low-cost process. In this chapter, an investigation is conducted into the potential uses of perovskite sensors in the realm of medical care. The application of perovskite sensors in the monitoring of vital signs, the detection of biomarkers, and the incorporation of such capabilities into wearable devices is receiving a lot of attention at the moment. This article delves further into the fundamentals of how perovskite sensors function, the many methods of their manufacture, as well as the difficulties and opportunities associated with using these sensors in medical settings. This chapter will throw light on the prospects that have surfaced in the area of perovskite sensors for monitoring physical health, as well as the improvements that have been achieved in the field of perovskite sensors. This chapter will shed light on the advances that have been made, which is the primary goal of the chapter.

Bionic prosthesis have revolutionized the field of medical science by providing individuals with limb loss the ability to regain functionality and independence. Traditional prosthetic materials, such as metals and plastics, have limitations in terms of weight, durability, and biocompatibility. The emergence of perovskite materials has opened up new possibilities for developing advanced bionic prosthesis. This chapter explores the application of perovskite materials in bionic prosthesis, highlighting their unique properties and potential advantages. It also discusses the challenges and future directions for utilizing perovskite materials in the development of next-generation bionic prosthesis.

 Energy harvesters based on perovskite nanomaterials have garnered significant attention in academia and industry because of their ability to transform mechanical and thermal energies into electric power. These materials have a great deal of promise for capturing body-induced and human activity-induced energy to power implantable and portable low-power devices. This book chapter builds upon previous works that have explored innovative materials and nanotechnologies for fabricating ferroelectric generators. We give a brief overview of flexible piezoelectric and pyroelectric energy harvesters' material selection procedure and reasonable microstructure design. We also stress the unique abilities of perovskite materials as energy collectors in biomedical applications, which include both conventional ferroelectrics and recently developed ferroelectric biomaterials. Additionally, we discuss the newest integration structures of hybrid generators with ferroelectric nanomaterials, which significantly enhance the functionalities of the energy harvesters, particularly for biological and implantable applications.

Within the context of the medical field, this chapter explores the possible uses of perovskite materials, piezoelectric nanogenerators (PENGs), piezoelectric biomaterials, and metal halide nanocrystals. As a result of their one-of-a-kind qualities, perovskite materials have recently gained attention as possible candidates for use in medical diagnostics, treatments, and imaging methods. However, before their broad application in the biomedical sector, difficulties relating to biocompatibility, stability, biodegradability, integration with current technologies, and scalability need to be overcome. PENGs provide self-powered health monitoring devices and may be utilized as a power source for microdevices and bio-implants, bypassing the limits of current power sources. PENGs are also capable of being employed as a power source for other applications. Theranostic methods, tissue regeneration, and drug delivery systems are all potential uses for piezoelectric biomaterials like BT, ZnO, and nanoparticles based on BFO. Nanocrystals made of metal halides, such as CsPbX3, have extraordinary light-harvesting capabilities that make them ideal for use in photonic-based biomedical applications. These applications include multi-photon excitation for cellular imaging and photoactivated treatment. Additional study is required to fully investigate the capabilities of these materials and find solutions to the obstacles that stand in the way of their clinical use. Some of these obstacles include biocompatibility, biodegradability, and tissue accumulation.

Piezoelectric perovskite materials have emerged as a promising class of materials due to their unique combination of piezoelectric properties, mechanical stability, and wide bandgap. This abstract presents an overview of the future prospects of piezoelectric perovskite materials, focusing on their potential applications and ongoing research efforts. The future prospects of piezoelectric perovskite materials lie in their application in various fields, including energy harvesting, sensors, actuators, and piezoelectric devices. These materials have the ability to convert mechanical energy into electrical energy and vice versa, offering opportunities for self-powered systems and wireless sensing applications. Additionally, their compatibility with flexible substrates opens up possibilities for the development of wearable and flexible electronics. One avenue of research focuses on lead-free perovskite materials, addressing the environmental concerns associated with lead-based perovskites. Extensive efforts have been made to explore alternative compositions, such as bismuthbased perovskites, which show promising piezoelectric properties. The development of lead-free perovskite materials will contribute to the sustainability and wider adoption of piezoelectric devices. Another area of interest is the integration of perovskite materials with other technologies, such as nanogenerators and energy storage systems. By combining piezoelectric perovskites with other functional materials, synergistic effects can be achieved, leading to enhanced performance and efficiency in energy conversion and storage. Furthermore, ongoing research is focused on improving the synthesis methods, understanding the fundamental mechanisms underlying the piezoelectric behavior, and optimizing the performance of piezoelectric perovskite materials. Advanced characterization techniques, including in-situ measurements and modeling approaches, are being employed to gain deeper insights into the material properties and enhance their performance.