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1.
Colloids Surf B Biointerfaces ; 222: 113077, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36577341

RESUMO

Magnetic hyperthermia (MH) has been studied for almost seventy-five years, but its efficacy in clinical applications is still fiercely contested. Despite this, few magnetic nanosystems are approved for clinical usage due to their strong affinity as drug carriers. The most important condition for hyperthermia applications for successful cancer therapy is magnetic nanoparticles with a controlled heating pattern (42-46 °C) for a prolonged timeframe. In the current study, cobalt-zinc nanoferrites (MNPs) having a Curie temperature of 46 â„ƒ with a tunable heating profile was loaded with Doxorubicin (DOX) through a surface conjugation technique (DOX-Cs-MNPs), and characterized by using multiple techniques. The magnetic hyterises (M-H) curves revealed the occurrence of superparamagnetism in the MNPs with extremely low coercivity; further, the DOX-loaded nanoparticles exhibited enhanced saturation magnetization. More importantly, the MNPs showed that they could maintain a therapeutic temperature for an indefinite amount of time. High drug loading affinity (86 %) was observed on MNPs with pH and temperature-controlled release. Under in vitro conditions, the biocompatible DOX-Cs-MNPs caused substantial apoptosis in MCF-7 cells (72 %) with overall cell death of < 95 %. The distinctive MNPs thus have the potential to be used in clinical applications.


Assuntos
Hipertermia Induzida , Nanopartículas de Magnetita , Neoplasias , Humanos , Zinco , Doxorrubicina/farmacologia , Doxorrubicina/química , Cobalto/farmacologia , Cobalto/química , Nanopartículas de Magnetita/química , Neoplasias/tratamento farmacológico
2.
Mater Sci Eng C Mater Biol Appl ; 129: 112366, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34579885

RESUMO

Carbon-based nanostructures with nanometer dimensions have been identified as potential photoluminescence probes for bioimaging due to their biocompatibility, tunable bandgap, and resistance to photobleaching. However, the influence of structural features of carbon quantum dots (CQDs) and graphene quantum dots (GQDs) in bioimaging has not been explored previously. In the present investigation, we elucidated the mechanism of higher PL in GQDs as compared to CQDs as a function of their structural features. TEM and AFM studies revealed that CQDs were spherical (size ~5 nm), while GQDs showed zigzag edges (size ~3 nm). Further, XRD and NMR studies confirmed that CQDs and GQDs show amorphous and crystalline structures with greater sp2 clusters, respectively. While both the QDs demonstrated multicolor fluorescence against variable excitations with similar lifetime, GQDs showed 7-fold higher QY than CQDs. Bioimaging studies in 2D cell culture, 3D tumoroids, and in vivo suggested a greater intensity of fluorescence in GQDs than CQDs. Additionally, rapid cell internalization was observed in GQDs owing to their positive surface potential by heterogeneous atomic (N and S) doping. Moreover, both CQDs and GQDs have demonstrated better time dependent stability for fluorescence properties. Taken together, the proposed mechanism elucidates the greater PL intensity in GQDs due to quantum confinement effect, crystallinity, and surface edge effects and is a better candidate for bioimaging amongst the carbon family.


Assuntos
Grafite , Pontos Quânticos , Carbono , Fluorescência
3.
Measur Sens ; 16: 100052, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36578268

RESUMO

World Health Organization (WHO) declares the COVID-19 outbreak as a pandemic. The newly emerging infection has caused around one million deaths worldwide and still counting. There is no specific treatment for the disease, and it can only contain by breaking the spread. So that early and rapid diagnosis of the infection is the only way to control the outbreak. The COVID-19 virus affects the human respiratory system and subsequently infects other vital organs. In consideration of the diagnosis, the present review focuses on the critical diagnostic approaches for COVID-19, including RT-PCR, Chest-CT scan, some biosensor-based systems, etc. Moreover, this review is a specific bird's eye view on recent developments on the point of care devices and related technologies. Additionally, it presented a small glimpse of the pathophysiology and structural aspects of COVID-19. Therefore, the current review can motivate and help the reader to develop cutting-edge diagnostic technologies for the early and rapid detection of the COVID-19.

4.
J Biomed Mater Res A ; 107(12): 2835-2847, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31433892

RESUMO

Poly(methyl methacrylate) (PMMA) bone cement is the most widely used grouting material in the joint arthroplasties and vertebroplasties. The present investigation has been carried out to scavenge the radicals and monomer by addition of an antioxidant to minimize the toxicity of bone cement (BC). The in silico studies were employed to determine the potent natural antioxidant at physiological conditions. The antioxidant methionine demonstrated a strong binding affinity with free radicals and methyl methacrylate (MMA) monomer than cysteine. The designated amount of methionine was optimized by various assay methods and >2% methionine shows strong scavenging capacity in BC. Moreover, the antioxidant-loaded BC (ABC) demonstrated similar handling, physicochemical and mechanical properties to pristine bone cement. Significantly, the developed formulation shows superior biological characteristics such as cell proliferation (2 ± 1 BC and 6 ± 1 ABC), adhesion (0.32 ± 0.02 BC and 0.54 ± 0.01 ABC), and cell viability (81 ± 2% BC and 93 ± 1% ABC) toward human osteoblast-like cells (MG-63). Therefore, the novel antioxidant bone cement is a potential candidate for various orthopedic applications to eliminate the adverse effects, related to residual toxic radical and monomer in bone cement.


Assuntos
Antioxidantes/farmacologia , Cimentos Ósseos/farmacologia , Metionina/farmacologia , Polimetil Metacrilato/farmacologia , Antioxidantes/química , Cimentos Ósseos/química , Cimentos Ósseos/toxicidade , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Teste de Materiais , Metionina/química , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Polimetil Metacrilato/química , Polimetil Metacrilato/toxicidade
5.
Med Hypotheses ; 126: 60-65, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31010501

RESUMO

Every year millions of lacerations and incisions taken place and require an effective methodology to manage the wound for a better life. The primary causes include mechanical trauma and surgical procedures. The rapid healing of the wound is critical to prevent further infection and reduction pain etc. Current options comprise of sutures, staplers, surgical strips and glues, again the intervention depends on the type of wound and the surgeon preference. The current wound closure techniques pose various potent limitations and confronting the problems to create a desired wound closure technique is necessary for faster and effective wound healing management. The surgical staplers are fast and easy to use wound closure devices, which approximates the edges of the wounds together by staples. The staples are mostly made up of metals like titanium and stainless steel. By modifying the existing stapling method using biodegradable staples that are expected to have good mechanical properties, not require removal procedure, minimized scarring and an overall acceleration in wound healing with minimal complications. Present, the paper focuses on the novel hypothesis on natural fiber reinforced biodegradable polymer staples as wound enclosures with high strength and degradability.


Assuntos
Materiais Biocompatíveis/química , Procedimentos Cirúrgicos Dermatológicos , Grampeamento Cirúrgico/métodos , Técnicas de Sutura/instrumentação , Suturas , Cicatrização , Animais , Humanos , Modelos Teóricos , Polímeros/química , Infecção da Ferida Cirúrgica , Ferimentos e Lesões/terapia
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