Facile synthesis of sericin modified graphene oxide nanocomposites for treating ischemic diseases

Radiopaque Silk Sericin Nanoparticles for Computed Tomography Imaging of Solid Tumors

Computed tomography (CT) is a non-invasive technology which is commonly used for cancer diagnosis owing to its high efficiency and widespread availability. But the inability to differentiate soft tissues with similar densities is the major limitation of CT. In the present study, silk sericin nanoparticles (SNP) prepared using the ethanol desolvation method were functionalized using diatrizoic acid (DTA). The prepared DTA-functionalized SNP (D-SNP) were spherical in shape with a mean hydrodynamic diameter of 52.6 nm. D-SNP were non-hemolytic and non-cytotoxic when treated with human erythrocytes and fibroblasts. D-SNP showed excellent in vitro CT imaging performance, with enhanced CT signals with the increase in the concentration of D-SNP, resulting in brighter CT images. In vivo experiments carried out using B16-F10 melanoma-bearing mice showed enhanced tumor visibility after 30 min of administration of D-SNP, thereby elucidating their efficient role as a CT contrast agent. The biosafety profile of D-SNP was studied by injecting the nanoparticles in BALB/c mice which did not show any change in hematology and serum biochemical analysis, which proved the non-toxic nature of D-SNP. Thus, D-SNP can be efficiently used for CT imaging of solid tumors.

Nanomaterials: Promising Tools for the Diagnosis and Treatment of Myocardial Infarction

Myocardial infarction (MI) is the leading cause of mortality from cardiovascular diseases. Rapid diagnosis and effective treatment are critical for improving patient prognosis. Although current diagnostic and therapeutic approaches have made significant progress, they still face challenges such as ischemia-reperfusion injury, microcirculatory disorders, adverse cardiac remodeling, and inflammatory responses. These issues highlight the urgent need for innovative solutions. Nanomaterials, with their diverse types, excellent physicochemical properties, biocompatibility, and targeting capabilities, offer promising potential in addressing these challenges. Advances in nanotechnology have increasingly drawn attention to the application of nanomaterials in both diagnosing and treating myocardial infarction. We summarize the pathophysiological mechanisms and staging of myocardial infarction. We systematically review the applications of nanomaterials in MI diagnosis, including the detection of biomarkers and imaging techniques, as well as in MI treatment, encompassing anti-inflammatory effects, antioxidant stress, inhibition of fibrosis, promotion of angiogenesis, and cardiac conduction repair. We analyze the existing challenges and provide insights into future research directions and potential solutions. Specifically, we discuss the need for rigorous safety assessments, long-term efficacy studies, and the development of robust strategies for translating laboratory findings into clinical practice. In conclusion, nanotechnology holds significant promise as a new strategy for diagnosing and treating myocardial infarction. Its potential to enhance clinical outcomes and revolutionize patient care makes it an exciting area of research with practical applications in real-world clinical settings.

Therapeutic potency of marine collagen/pectin scaffolds - Fabrication, characterization and evaluation

Skin is an important vital organ that must be given proper care and protection from external damage and harmful microbes. If injured, it must be treated with an ideal wound dressing material with potent hemostatic and non-toxic properties. In the present study, fish collagen (FC) was extracted from the fins and tails of Black pomfret (Parastromateus niger). The isolated fish collagen was homogenized with pectin (P) and freeze dried to obtain fish collagen/pectin (FC/P) scaffolds. Scanning electron microscopic analysis showed the porous nature of scaffolds with intermittent holes. UV-Visible and Fourier infrared spectroscopic analyses demonstrated the physicochemical properties of FC/P scaffolds. Hemolytic assay performed using human blood demonstrated the percentage of hemolysis as 0.5 %. In vitro blood clotting assay carried out to determine the hemostatic behaviour displayed the formation of blood clot within 60 s in the presence of FC/P scaffolds. 95 % of cells were viable with the highest concentration of FC/P scaffold used for MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. Scratch wound assay demonstrated complete closure of wound in FC/P scaffold treated cells after 48 h of treatment. Chick embryo chorioallantoic membrane (CAM) assay showed the development of new blood vessels within 6 h of incubation with the FC/P scaffolds, thereby proving their angiogenic potency. These results indicate the potential use of FC/P scaffolds as effective biomaterials for tissue regenerative applications.

Sericin coats of silk fibres, a degumming waste or future material?

Silk is a fibrous biopolymer with a recorded history in the textile industries for centuries. This fibre is constituted of two different proteins: fibroin and sericin, of which the latter accounting for approximately 20-30 % of the silk mass. Silk sericin (SSER) was previously considered as a waste by-product in silk fibroin extraction. SSER has recently garnered significant scientific interest due to its extensive biological and pharmacological properties. These include antioxidant effects, biocompatibility, low immunogenicity, controlled biodegradability, and the ability to induce cell proliferation. This review covers studies about various aspects of this emerging material, namely, its general morphology, specific structure, molecular weight, features of different layers, and gene sequences. The impact of different extraction methods and the application of extracted SSER based on molecular weight are discussed. Additionally, the characteristic functional groups in the amino acids of sericin facilitate its applications in regenerative medicine, wound healing, drug delivery, textile, environment, and energy, in various forms like hydrogels, films, scaffolds, and conduits. SSER-based materials offer great potentials for multi-functional applications in the upcoming decades, showcasing adaptability for various functional uses and promising future technological advancements.

Haemostatic potency of sodium alginate/aloe vera/sericin composite scaffolds - preparation, characterisation, and evaluation

Fabrication of haemostatic materials with excellent antimicrobial, biocompatible and biodegradable properties remains as a major challenge in the field of medicine. Haemostatic agents play vital role in protecting patients and military individuals during emergency situations. Natural polymers serve as promising materials for fabricating haemostatic compounds due to their efficacy in promoting hemostasis and wound healing. In the present work, sodium alginate/aloe vera/sericin (SA/AV/S) scaffold has been fabricated using a simple cost-effective casting method. The prepared SA/AV/S scaffolds were characterised for their physicochemical properties such as scanning electron microscope, UV-visible spectroscopy and Fourier transform infra-red spectroscopy. SA/AV/S scaffold showed good mechanical strength, swelling behaviour and antibacterial activity. In vitro experiments using erythrocytes proved the hemocompatible and biocompatible features of SA/AV/S scaffold. In vitro blood clotting assay performed using human blood demonstrated the haemostatic and blood absorption properties of SA/AV/S scaffold. Scratch wound assay was performed to study the wound healing efficacy of prepared scaffolds. Chick embryo chorioallantoic membrane assay carried out using fertilised embryos proved the angiogenic property of SA/AV/S scaffold. Thus, SA/AV/S scaffold could serve as a potential haemostatic healthcare product due to its outstanding haemostatic, antimicrobial, hemocompatible, biocompatible and angiogenic properties.

Carbon materials and their metal composites for biomedical applications: A short review

Carbon materials and their hybrid metal composites have garnered significant attention in biomedical applications due to their exceptional biocompatibility. This biocompatibility arises from their inherent chemical stability and low toxicity within biological systems. This review offers a comprehensive overview of carbon nanomaterials and their metal composites, emphasizing their biocompatibility-focused applications, including drug delivery, bioimaging, biosensing, and tissue engineering. The paper outlines advancements in surface modifications, coatings, and functionalization techniques designed to enhance the biocompatibility of carbon materials, ensuring minimal adverse effects in biological systems. A comprehensive investigation into hybrid composites integrating carbon nanomaterials is conducted, categorizing them as fullerenes, carbon quantum dots, carbon nanotubes, carbon nanofibers, graphene, and diamond-like carbon. The concluding section addresses regulatory considerations and challenges associated with integrating carbon materials into medical devices. This review culminates by providing insights into current achievements, challenges, and future directions, underscoring the pivotal role of carbon nanomaterials and their metal composites in advancing biocompatible applications.

Nanotechnology in coronary heart disease

Coronary heart disease (CHD) is one of the major causes of death and disability worldwide, especially in low- and middle-income countries and among older populations. Conventional diagnostic and therapeutic approaches have limitations such as low sensitivity, high cost and side effects. Nanotechnology offers promising alternative strategies for the diagnosis and treatment of CHD by exploiting the unique properties of nanomaterials. In this review, we use bibliometric analysis to identify research hotspots in the application of nanotechnology in CHD and provide a comprehensive overview of the current state of the art. Nanomaterials with enhanced imaging and biosensing capabilities can improve the early detection of CHD through advanced contrast agents and high-resolution imaging techniques. Moreover, nanomaterials can facilitate targeted drug delivery, tissue engineering and modulation of inflammation and oxidative stress, thus addressing multiple aspects of CHD pathophysiology. We discuss the application of nanotechnology in CHD diagnosis (imaging and sensors) and treatment (regulation of macrophages, cardiac repair, anti-oxidative stress), and provide insights into future research directions and clinical translation. This review serves as a valuable resource for researchers and clinicians seeking to harness the potential of nanotechnology in the management of CHD. STATEMENT OF SIGNIFICANCE: Coronary heart disease (CHD) is the one of leading cause of death and disability worldwide. Nanotechnology offers new strategies for diagnosing and treating CHD by exploiting the unique properties of nanomaterials. This review uses bibliometric analysis to uncover research trends in the use of nanotechnology for CHD. We discuss the potential of nanomaterials for early CHD detection through advanced imaging and biosensing, targeted drug delivery, tissue engineering, and modulation of inflammation and oxidative stress. We also offer insights into future research directions and potential clinical applications. This work aims to guide researchers and clinicians in leveraging nanotechnology to improve CHD patient outcomes and quality of life.

A review on background, process and application of electrospun nanofibers for tissue regeneration

Electrospinning is a versatile method which is used to synthesize nano/micro sized fibers under the influence of electric field. Electrospun nanoscaffolds are one of the widely accepted platforms for cultivating soft and hard tissues as they create a prefect micro-environment for cell adhesion, proliferation and differentiation. Nanoscaffolds are widely used in the field of tissue engineering due to their versatility in aiding the growth of different types of cells and tissues for varied applications. The composition, molecular weight and structure of polymer used to fabricate nanoscaffold plays an important role in determining the size and strength of the nanofibers prepared. This review gives information about the background, process and different types of polymers used in electrospinning. Recent advances in culturing liver cells, osteoblasts, skin cells, neural cells and coronary artery smooth muscle cells on nanoscaffolds are also elucidated.

Influence of pH in the synthesis of calcium phosphate based nanostructures with enhanced bioactivity and pro-angiogenic properties

In synthetic fabrication, the process parameters decide the growth nucleation, phase translation, and the evolution of morphological facets of nanostructured materials. This work demonstrates the formation of different crystallographic phases of calcium phosphate by the influence of pH from acidic to alkaline conditions and also investigated their bone regeneration, protein adsorption, and pro-angiogenic properties. Present results illustrate that the alteration of pH is the crucial factor for the synthesis of calcium phosphate (CP) phases. The structural analysis reveals the monetite (CaHPO₄ ) phase with a triclinic crystal system for pH 5, dual-phase of monetite combined with hydroxyapatite at the neutral pH 7, and pure phase of hydroxyapatite (Ca₁₀ [PO₄ ]₆ OH₂ ) with hexagonal structure at pH 10. Microscopic analysis portrays the cubic and rod-like morphologies by changing the pH values. FTIR and RAMAN spectroscopic analyses confirm the stretching, bending, and vibrational modes of dominant phosphate groups of different CP phases. Further, the biocompatibility of the prepared CP phases was examined by hemolysis assay, which showed less than 2% of lysis and enhanced cell viability. Moreover, the bioactivity study revealed rapid mineralization and a higher protein adsorption rate for the monetite CP phase (M-CP). Subsequently, the chick embryo angiogenesis assay elucidated 33% higher neovascularization for M-CP compared with the other two CP phases. The fabricated M-CP nanostructure constitutes a promising candidate for biomedical applications.

Sericin/Human Placenta-Derived Extracellular Matrix Scaffolds for Cutaneous Wound Treatment-Preparation, Characterization, In Vitro and In Vivo Analyses

Human placenta is loaded with an enormous amount of endogenous growth factors, thereby making it a superior biomaterial for tissue regeneration. Sericin is a naturally occurring silk protein that is extensively used for biomedical applications. In the present work, sericin and human placenta-derived extracellular matrix were blended and fabricated in the form of scaffolds using the freeze-drying method for cutaneous wound treatment. The prepared sericin/placenta-derived extracellular matrix (SPEM) scaffolds were characterized to determine their morphology, functional groups, mechanical strength, and antibacterial activity. Scanning electron microscopic analysis of the scaffolds showed smooth surfaces with interconnected pores. In vitro MTT and scratch wound assays performed using HaCaT cells proved the non-toxic and wound-healing efficacy of SPEM scaffolds. In vivo CAM assay using fertilized chick embryos proved the angiogenic potency of the scaffolds. Animal experiments using Wistar albino rats proved that the open excision wounds treated with SPEM scaffolds significantly reduced wound size with collagen deposition. These results confirm that SPEM scaffolds can serve as a promising biomaterial for tissue regeneration.

PEGylation of Goldbody: PEG-aided conformational engineering of peptides on gold nanoparticles

It is still a great challenge to engineer flexible non-functional molecules into special conformations to carry out novel functions. Previously, we successfully restored the native conformations and functions of the flexible complementary-determining regions (CDRs) of antibodies on the surface of gold nanoparticles (AuNPs), and created a class of AuNP-based artificial antibodies, denoted as Goldbodies. Yet, in these Goldbodies, there are dozens of CDRs on one Goldbody. Herein, we show that the number of CDRs per Goldbody could be reduced by more than one order of magnitude, by replacing the majority of the CDRs with polyethylene glycol (PEG) with a molecular weight around 600 Da, while the native conformations and functions of the CDRs could still be restored on AuNPs. Also, we find that the PEG with two terminal -SH groups is much better than the PEG with a single -SH group for aiding the restoration of the native conformation of the CDRs on AuNPs. To demonstrate the potential generic applicability of the PEGylation in aiding conformational engineering of peptides, two PEGylated Goldbodies have been created, which can specifically recognize lysozyme and epidermal growth factor receptor, respectively. The PEGylated Goldbodies further prove the mechanism of conformational engineering and the "Confined Lowest Energy Fragments" (CLEFs) hypothesis, and pave the way for future applications of Goldbodies.