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1.
AAPS PharmSciTech ; 25(5): 127, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844724

RESUMO

The success of obtaining solid dispersions for solubility improvement invariably depends on the miscibility of the drug and polymeric carriers. This study aimed to categorize and select polymeric carriers via the classical group contribution method using the multivariate analysis of the calculated solubility parameter of RX-HCl. The total, partial, and derivate parameters for RX-HCl were calculated. The data were compared with the results of excipients (N = 36), and a hierarchical clustering analysis was further performed. Solid dispersions of selected polymers in different drug loads were produced using solvent casting and characterized via X-ray diffraction, infrared spectroscopy and scanning electron microscopy. RX-HCl presented a Hansen solubility parameter (HSP) of 23.52 MPa1/2. The exploratory analysis of HSP and relative energy difference (RED) elicited a classification for miscible (n = 11), partially miscible (n = 15), and immiscible (n = 10) combinations. The experimental validation followed by a principal component regression exhibited a significant correlation between the crystallinity reduction and calculated parameters, whereas the spectroscopic evaluation highlighted the hydrogen-bonding contribution towards amorphization. The systematic approach presented a high discrimination ability, contributing to optimal excipient selection for the obtention of solid solutions of RX-HCl.


Assuntos
Química Farmacêutica , Excipientes , Polímeros , Cloridrato de Raloxifeno , Solubilidade , Difração de Raios X , Polímeros/química , Excipientes/química , Cloridrato de Raloxifeno/química , Análise Multivariada , Difração de Raios X/métodos , Química Farmacêutica/métodos , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Microscopia Eletrônica de Varredura/métodos , Ligação de Hidrogênio , Cristalização/métodos
2.
Anal Chem ; 96(25): 10467-10475, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38863336

RESUMO

"Signal-off" nanozyme sensing platforms are usually employed to detect analytes (e.g., ascorbic acid (AA) and alkaline phosphatase (ALP)), which are mostly based on oxidase (OXD) nanozymes. However, their drawbacks, like dissolved oxygen-dependent catalysis capability, relatively low enzyme activity, limited amount, and kind, may not favor sensing platforms' optimization. Meanwhile, with the need for sustainable development, a reusable "signal-off" sensing platform is essential for cutting down the cost of the assay, but it is rarely developed in previous studies. Magnetic peroxidase (POD) nanozymes potentially make up the deficiencies and become reusable and better "signal-off" sensing platforms. As a proof of concept, we first construct Fe3O4@polydopamine-supported Pt/Ru alloy nanoparticles (IOP@Pt/Ru) without stabilizers. IOP@Pt/Ru shows high POD activity with Vmax of 83.24 × 10-8 M·s-1 for 3,3',5,5'-Tetramethylbenzidine (TMB) oxidation. Meanwhile, its oxidation rate for TMB is slower than the reduction of oxidized TMB by reducers, favorable for a more significant detection signal. On the other hand, IOP@Pt/Ru possesses great magnet-responsive capability, making itself be recycled and reused for at least 15-round catalysis. When applying IOP@Pt/Ru for AA (ALP) detection, it performs better detectable adaptability, with a linear range of 0.01-0.2 mM (0.1-100 U/L) and a limit of detection of 0.01 mM (0.05 U/L), superior to most of OXD nanozyme-based ALP sensing platform. Finally, IOP@Pt/Ru's reusable assay was demonstrated in real blood samples for ALP assay, which has never been explored in previous studies. Overall, this study develops a reusable "signal-off" nanozyme sensing platform with superior assay capabilities than traditional OXD nanozymes, paves a new way to optimize nanozyme-based "signal-off" sensing platforms, and provides an idea for constructing inexpensive and sustainable sensing platforms.


Assuntos
Ligas , Peroxidase , Platina , Platina/química , Ligas/química , Peroxidase/química , Peroxidase/metabolismo , Benzidinas/química , Limite de Detecção , Oxirredução , Polímeros/química , Humanos , Catálise , Técnicas Biossensoriais/métodos , Ácido Ascórbico/análise , Ácido Ascórbico/química , Indóis
3.
ACS Appl Bio Mater ; 7(7): 4702-4709, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38910532

RESUMO

A label-free electrochemical immunosensor was developed for the rapid and sensitive detection of neuron-specific enolase (NSE). The electropolymerization of dopamine in conjunction with highly conductive carbon nanotubes offers a simple and quick platform for the direct anchoring of antibodies without the assistance of any coupling agent as well as a blocking agent. The developed immunosensor exhibited a wider detection range from 120 pM (9 ng mL-1) to 3 nM (200 ng mL-1) for NSE with a high sensitivity of 3.9 µA pM-1 cm-2 in 0.1 M phosphate-buffered saline (PBS) at physiological pH (7.4). Moreover, the short recognition time (15 min) for the antigen enabled the detection to be fast and less invasive. Additionally, the evaluation of a rate constant at various concentrations of NSE via feedback mode of scanning electrochemical microscopy (SECM) explained the profound effect of antigen concentration on the rate of flow of electrons. Therefore, the proposed immunosensor can be a promising tool for the early detection of small cell lung cancer in a very short period of time with consistent accuracy.


Assuntos
Materiais Biocompatíveis , Técnicas Biossensoriais , Indóis , Nanotubos de Carbono , Fosfopiruvato Hidratase , Polímeros , Nanotubos de Carbono/química , Fosfopiruvato Hidratase/imunologia , Fosfopiruvato Hidratase/metabolismo , Fosfopiruvato Hidratase/análise , Polímeros/química , Indóis/química , Humanos , Imunoensaio/métodos , Materiais Biocompatíveis/química , Teste de Materiais , Tamanho da Partícula , Técnicas Eletroquímicas
4.
Sensors (Basel) ; 24(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38733009

RESUMO

Recent advancements in polymer-assisted layer-by-layer (LbL) fabrication have revolutionized the development of wearable sensors for health monitoring. LbL self-assembly has emerged as a powerful and versatile technique for creating conformal, flexible, and multi-functional films on various substrates, making it particularly suitable for fabricating wearable sensors. The incorporation of polymers, both natural and synthetic, has played a crucial role in enhancing the performance, stability, and biocompatibility of these sensors. This review provides a comprehensive overview of the principles of LbL self-assembly, the role of polymers in sensor fabrication, and the various types of LbL-fabricated wearable sensors for physical, chemical, and biological sensing. The applications of these sensors in continuous health monitoring, disease diagnosis, and management are discussed in detail, highlighting their potential to revolutionize personalized healthcare. Despite significant progress, challenges related to long-term stability, biocompatibility, data acquisition, and large-scale manufacturing are still to be addressed, providing insights into future research directions. With continued advancements in polymer-assisted LbL fabrication and related fields, wearable sensors are poised to improve the quality of life for individuals worldwide.


Assuntos
Técnicas Biossensoriais , Polímeros , Dispositivos Eletrônicos Vestíveis , Polímeros/química , Humanos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos
5.
Sci Rep ; 14(1): 11795, 2024 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782942

RESUMO

The clinical finite element analysis (FEA) application in maxillofacial surgery for mandibular fracture is limited due to the lack of a validated FEA model. Therefore, this study aims to develop a validated FEA model for mandibular fracture treatment, by assessing non-comminuted mandibular fracture fixation. FEA models were created for mandibles with single simple symphysis, parasymphysis, and angle fractures; fixated with 2.0 mm 4-hole titanium miniplates located at three different configurations with clinically known differences in stability, namely: superior border, inferior border, and two plate combinations. The FEA models were validated with series of Synbone polymeric mandible mechanical testing (PMMT) using a mechanical test bench with an identical test set-up. The first outcome was that the current understanding of stable simple mandibular fracture fixation was reproducible in both the FEA and PMMT. Optimal fracture stability was achieved with the two plate combination, followed by superior border, and then inferior border plating. Second, the FEA and the PMMT findings were consistent and comparable (a total displacement difference of 1.13 mm). In conclusion, the FEA and the PMMT outcomes were similar, and hence suitable for simple mandibular fracture treatment analyses. The FEA model can possibly be applied for non-routine complex mandibular fracture management.


Assuntos
Placas Ósseas , Análise de Elementos Finitos , Fixação Interna de Fraturas , Mandíbula , Fraturas Mandibulares , Fraturas Mandibulares/cirurgia , Humanos , Mandíbula/cirurgia , Mandíbula/fisiologia , Fenômenos Biomecânicos , Fixação Interna de Fraturas/métodos , Testes Mecânicos , Titânio , Estresse Mecânico , Polímeros/química
6.
J Environ Manage ; 360: 121210, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38781878

RESUMO

The food industry requires new production models that include more environmentally friendly waste management practices, considering that the environmental loads of solid waste and wastewater associated with this sector cause damage to the receiving ecosystems. The approach considered in this study focuses on the design and environmental assessment of an enzymatic process for the valorization of ferulic acid present in the effluent of a corn tortilla plant. The ferulic acid can be immobilized on chitosan so that the ferulic acid grafted chitosan can be used as a bioactive film with enhanced antioxidant properties with potential applications in the biotechnology sector. Its real projection approach requires the evaluation of its environmental and economic performance, trying to identify its benefits and potential in the value chain, using the Techno-Economic Analysis (TEA) as a phase for the conceptual design of the process and the Life Cycle Assessment (LCA) methodology for the environmental evaluation. It should be noted that the TEA indicators are promising, since the values of the financial indicators obtained are representative of the economic profitability, which makes the ferulic acid valorization a viable process. In terms of the environmental impact of the process, the buffer dose and the chitosan production process are identified as the main critical points. This double benefit in environmental and economic terms shows that the valorization of ferulic acid for chitosan functionalization is a promising alternative to improve the sustainability performance of corn processing.


Assuntos
Quitosana , Ácidos Cumáricos , Zea mays , Quitosana/química , Ácidos Cumáricos/química , Polímeros/química , Gerenciamento de Resíduos/métodos
7.
PeerJ ; 12: e17237, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699192

RESUMO

Background: Root perforation repair presents a significant challenge in dentistry due to inherent limitations of existing materials. This study explored the potential of a novel polydopamine-based composite as a root repair material by evaluating its sealing efficacy, radiopacity, and surface topography. Methods: Confocal microscopy assessed sealing ability, comparing the polydopamine-based composite to the gold standard, mineral trioxide aggregate (MTA). Radiopacity was evaluated using the aluminium step wedge technique conforming to ISO standards. Surface roughness analysis utilized atomic force microscopy (AFM), while field emission scanning electron microscopy (FESEM) visualized morphology. Results: The polydopamine-based composite exhibited significantly superior sealing efficacy compared to MTA (P < 0.001). Radiopacity reached 3 mm aluminium equivalent, exceeding minimum clinical requirements. AFM analysis revealed a smooth surface topography, and FESEM confirmed successful composite synthesis. Conclusion: This study demonstrates promising properties of the polydopamine-based composite for root perforation repair, including superior sealing efficacy, clinically relevant radiopacity, and smooth surface topography. Further investigation is warranted to assess its clinical viability and potential translation to endodontic practice.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Indóis , Óxidos , Polímeros , Materiais Restauradores do Canal Radicular , Silicatos , Propriedades de Superfície , Polímeros/química , Indóis/química , Silicatos/química , Compostos de Cálcio/química , Óxidos/química , Materiais Restauradores do Canal Radicular/química , Compostos de Alumínio/química , Humanos , Combinação de Medicamentos , Microscopia Eletrônica de Varredura , Microscopia de Força Atômica/métodos , Microscopia Confocal , Teste de Materiais , Raiz Dentária/lesões , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/cirurgia
8.
ACS Sens ; 9(5): 2294-2309, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38654679

RESUMO

Bioanalyte collection by blood draw is a painful process, prone to needle phobia and injuries. Microneedles can be engineered to penetrate the epidermal skin barrier and collect analytes from the interstitial fluid, arising as a safe, painless, and effective alternative to hypodermic needles. Although there are plenty of reviews on the various types of microneedles and their use as drug delivery systems, there is a lack of systematization on the application of polymeric microneedles for diagnosis. In this review, we focus on the current state of the art of this field, while providing information on safety, preclinical and clinical trials, and market distribution, to outline what we believe will be the future of health monitoring.


Assuntos
Agulhas , Polímeros , Humanos , Polímeros/química , Sistemas de Liberação de Medicamentos/instrumentação , Animais , Microinjeções/instrumentação , Microinjeções/métodos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos
9.
Int J Numer Method Biomed Eng ; 40(6): e3827, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38623951

RESUMO

A prosthetic knee is designed to replace the functionality of an anatomical knee in transfemoral amputees. The purpose of a prosthetic knee is to restore mobility and compensate amputees for their impairment. In the present research numerical modelling and simulation of a carbon fabric reinforced polymer made polycentric prosthetic knee with four-bar mechanism was performed. Virtual prototyping with computer-aided design and computer-aided engineering software ensured geometric and structural stability of the knee design. The linkage mechanism, instantaneous centre's location and trajectory were investigated using multibody dynamics and analytical formulations. Computational simulations with a non-linear finite element model were employed with joints, contact formulations and an orthotropic material model to predict the displacement, stress formulated and life of the knee prosthesis under static and cyclic loading conditions. Finite element analysis assessed the strength and durability of knee in accordance to standards. Maximum Principal stress of 155 MPa and life expectancy of 3.1 × 106 cycles were determined for the composite knee through numerical simulations ensuring a safe design. Experimental testing was also conducted as per standards and the percentage error was estimated to be 2.52%, thereby establishing the validity of the finite element model deployed. This type of simulation-based approach can be implemented to efficiently and affordably design and prototype a prosthetic knee with desired functioning criteria.


Assuntos
Análise de Elementos Finitos , Prótese do Joelho , Polímeros , Desenho de Prótese , Humanos , Polímeros/química , Simulação por Computador , Fibra de Carbono/química , Desenho Assistido por Computador , Carbono/química , Estresse Mecânico , Teste de Materiais
10.
Sensors (Basel) ; 24(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38676201

RESUMO

This paper presents an enhanced version of our previously developed bio-optical transceiver, presenting a significant advancement in nanosensor technology. Using self-assembled polymers, this nanodevice is capable of electron detection while maintaining biocompatibility, an essential feature for in vivo medical biosensors. This enhancement finds significance in the field of infectious disease control, particularly in the early detection of respiratory viruses, including high-threat pathogens such as SARS-CoV-2. The proposed system harnesses bioluminescence by converting electric signaling to visible blue light, effectively opening the path of linking nano-sized mechanisms to larger-scale systems, thereby pushing the boundaries of in vivo biomedical sensing. The performance evaluation of our technology is analytical and is based on the use of Markov chains, through which we assess the bit error probability. The calculated improvements indicate that this technology qualifies as a forerunner in terms of supporting the communication needs of smaller, safer, and more efficient manufactured sensor technologies for in vivo medical applications.


Assuntos
Técnicas Biossensoriais , COVID-19 , SARS-CoV-2 , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , SARS-CoV-2/isolamento & purificação , COVID-19/diagnóstico , COVID-19/virologia , Humanos , Desenho de Equipamento , Polímeros/química , Cadeias de Markov
11.
Biomed Phys Eng Express ; 10(4)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38670074

RESUMO

Background. New applications of 3D printing have recently appeared in the fields of radiotherapy and radiology, but the knowledge of many radiological characteristics of the compounds involved is still limited. Therefore, studies are needed to improve our understanding about the transport and interaction of ionizing radiation in these materials.Purpose. The purpose of this study is to perform an analysis of the most important radiation interaction parameters in thermoplastic materials used in Fused Deposition Modeling 3D printing. Additionally, we propose improvements to bring their characteristics closer to those of water and use them as water substitutes in applications such as radiodiagnosis, external radiotherapy, and brachytherapy.Methods. We have calculated different magnitudes as mass linear attenuation, mass energy absorption coefficients, as well as stopping power and electronic density of several thermoplastic materials along with various compounds that have been used as water substitutes and in a new proposed blend. To perform these computations, we have used the XCOM and ESTAR databases from NIST and the EGSnrc code for Montecarlo simulations.Results. From the representation of the calculated interaction parameters, we have been able to establish relationships between their properties and the proportion of certain chemical elements. In addition, studying these same characteristics in different commercial solutions used as substitutes for water phantoms allows us to extrapolate improvements for these polymers.Conclusion. The radiological characteristics of the analyzed thermoplastic materials can be improved by adding some chemical elements with atomic numbers higher than oxygen and by using polyethylene in new blends.


Assuntos
Polímeros , Impressão Tridimensional , Água , Água/química , Polímeros/química , Método de Monte Carlo , Imagens de Fantasmas , Plásticos/química , Simulação por Computador , Humanos , Braquiterapia/métodos
12.
Environ Sci Pollut Res Int ; 31(18): 27329-27344, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38512577

RESUMO

Recently, the usage of a cold-bonded method in the production of artificial green geopolymer coarse aggregates (GCA) has been crucial from an economic and environmental perspective because the sintering method consumes an enormous quantity of energy and generates a significant quantity of pollutants. This research investigated the manufacture of GCA via cold-bonded pelletization using two distinct industrial byproducts (GGBFS and FA) via a new and simpler pelletization technology. Three different binders were used to produce three distinct types of GCAs as partial replacements for natural coarse aggregate (NCA) at varying replacement rates (0%, 25%, 50%, and 75%). The first group used ground-granulated blast furnace slag, while the second used GGBFS with perlite, and the third used FA with perlite. An alkaline activator was commonly used with all three groups. The physical and mechanical properties of three distinct varieties of GCA were recorded. The results indicated that the mechanical and chemical properties of three different types of GCAs were nearly identical to those of natural aggregate, with the exception of their increased water absorption. According to the findings, the recommended mixtures were suitable for usage in the construction industry. The results indicated that the ratio of all investigated attributes declined as the number of GCAs increased. In contrast, lightweight concrete can be obtained at a ratio of GCA (FA with perlite) equal to 75%, where unit weight, compressive, splitting tensile, flexural, and water absorption strengths were 1.87 gm/cm3, 20.2 MPa, 1.8 MPa, 8 MPa, and 6.0%, respectively (FA with perlite).


Assuntos
Materiais de Construção , Polímeros/química , Indústria da Construção
13.
Anal Sci ; 40(4): 773-780, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38413474

RESUMO

In this study, capillary sieving electrophoresis (CSE) using polymer solutions was used to evaluate the structural changes in nucleic acids upon complexation with small molecules. As the model target and nucleic acids, L-tyrosinamide (Tyr-Am) and its aptamer, which is a type of DNA specifically binding to Tyr-Am, were selected. CSE was conducted using a capillary filled with background solution (BGS) containing hydroxypropyl cellulose (HPC) as a sieving matrix. When Tyr-Am or tyrosine was added to the BGS in CSE, the ratio of mobility differences of the Tyr-Am-aptamer complex increased compared to that of the free aptamer without the addition of Tyr-Am. In contrast, when other amino acids or their analogs were added, results showed no apparent change or decreases in electrophoretic mobility. These results indicate that the proposed method can be applied to assess structural changes in nucleic acids that target small molecules.


Assuntos
DNA , Ácidos Nucleicos , Eletroforese Capilar/métodos , Polímeros/química , Oligonucleotídeos
14.
ACS Appl Bio Mater ; 7(1): 131-143, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38079569

RESUMO

Smart materials with controlled stimuli-responsive functions are at the forefront of technological development. In this work, we present a generic strategy that combines simple components, physicochemical responses, and easy fabrication methods to achieve a dual stimuli-responsive system capable of location-specific antimicrobial cargo delivery. The encapsulated system is fabricated by combining a biocompatible inert polymeric matrix of poly(dimethylsiloxane) (PDMS) and a bioactive cargo of saturated fatty acids. We demonstrate the effectiveness of our approach to deliver antimicrobial activity for the model bacteria Escherichia coli. The system responds to two control variables, temperature and pH, delivering two levels of antimicrobial response under distinct combinations of stimuli: one response toward the planktonic media and another response directly at the surface for sessile bacteria. Spatially resolved Raman spectroscopy alongside thermal and structural material analysis reveals that the system not only exhibits ON/OFF states but can also control relocation and targeting of the active cargo toward either the surface or the liquid media, leading to different ON/OFF states for the planktonic and sessile bacteria. The approach proposed herein is technologically simple and scalable, facing low regulatory barriers within the food and healthcare sectors by using approved components and relying on fundamental chemical processes. Our results also provide a proof-of-concept platform for the design and easy fabrication of delivery systems capable of operating as Boolean logic gates, delivering different responses under different environmental conditions.


Assuntos
Produtos Biológicos , Temperatura , Polímeros/química , Escherichia coli , Concentração de Íons de Hidrogênio
15.
AAPS PharmSciTech ; 24(7): 203, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37783961

RESUMO

The primary focus of the research is to study the role of cocrystal and amorphous solid dispersion approaches for enhancing solubility and preserving the stability of a poorly soluble drug, i.e., ibuprofen (IBP). First, the solvent-assisted grinding approach determined the optimum molar ratio of the drug and the coformer (nicotinamide (NIC)). Later, the polymeric filaments of cocrystals and amorphous solid dispersions were developed using the hot melt extrusion (HME) process, and the printlets were fabricated using the fused deposition modeling (FDM) additive manufacturing process. In addition, the obtained filaments were also milled and compressed into tablets as reference samples. The formation of cocrystals and amorphous solid dispersions was evaluated and confirmed using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (PXRD) analysis. The drug release profiles of 3D printlets with 50% infill were found to be faster and are in line with the release profiles of compressed tablets. In addition, the 3D-printed cocrystal formulation was stable for 6 months at accelerated conditions. However, the 3D printlets of amorphous solid dispersions and compressed tablets failed to retain stability attributed to the recrystallization of the drug and loss in tablet mechanical properties. This shows the suitability of a cocrystal platform as a novel approach for developing stable formulations of poorly soluble drug substances over amorphous solid dispersions.


Assuntos
Tecnologia de Extrusão por Fusão a Quente , Ibuprofeno , Solubilidade , Tecnologia de Extrusão por Fusão a Quente/métodos , Liberação Controlada de Fármacos , Polímeros/química , Composição de Medicamentos/métodos , Comprimidos
16.
Biosensors (Basel) ; 13(6)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37366951

RESUMO

Nowadays, virus pandemics have become a major burden seriously affecting human health and social and economic development. Thus, the design and fabrication of effective and low-cost techniques for early and accurate virus detection have been given priority for prevention and control of such pandemics. Biosensors and bioelectronic devices have been demonstrated as promising technology to resolve the major drawbacks and problems of the current detection methods. Discovering and applying advanced materials have offered opportunities to develop and commercialize biosensor devices for effectively controlling pandemics. Along with various well-known materials such as gold and silver nanoparticles, carbon-based materials, metal oxide-based materials, and graphene, conjugated polymer (CPs) have become one of the most promising candidates for preparation and construction of excellent biosensors with high sensitivity and specificity to different virus analytes owing to their unique π orbital structure and chain conformation alterations, solution processability, and flexibility. Therefore, CP-based biosensors have been regarded as innovative technologies attracting great interest from the community for early diagnosis of COVID-19 as well as other virus pandemics. For providing precious scientific evidence of CP-based biosensor technologies in virus detection, this review aims to give a critical overview of the recent research related to use of CPs in fabrication of virus biosensors. We emphasize structures and interesting characteristics of different CPs and discuss the state-of-the-art applications of CP-based biosensors as well. In addition, different types of biosensors such as optical biosensors, organic thin film transistors (OTFT), and conjugated polymer hydrogels (CPHs) based on CPs are also summarized and presented.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanopartículas Metálicas , Vírus , Humanos , Polímeros/química , COVID-19/diagnóstico , Prata , Técnicas Biossensoriais/métodos
17.
Int J Nanomedicine ; 18: 1577-1595, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007986

RESUMO

Purpose: The research objective is to design intranasal brain targeted CLZ loaded lecithin based polymeric micelles (CLZ- LbPM) aiming to improve central systemic CLZ bioavailability. Methods: In our study, intranasal CLZ loaded lecithin based polymeric micelles (CLZ- LbPM) were formulated using soya phosphatidyl choline (SPC) and sodium deoxycholate (SDC) with different CLZ:SPC:SDC ratios via thin film hydration technique aiming to enhance drug solubility, bioavailability and nose to brain targeting efficiency. Optimization of the prepared CLZ-LbPM using Design-Expert® software was achieved showing that M6 which composed of (CLZ:SPC: SDC) in respective ratios of 1:3:10 was selected as the optimized formula. The optimized formula was subjected to further evaluation tests as, Differential Scanning Calorimetry (DSC), TEM, in vitro release profile, ex vivo intranasal permeation and in vivo biodistribution. Results: The optimized formula with the highest desirability exhibiting (0.845), small particle size (12.23±4.76 nm), Zeta potential of (-38 mV), percent entrapment efficiency of > 90% and percent drug loading of 6.47%. Ex vivo permeation test showed flux value of 27 µg/cm².h and the enhancement ratio was about 3 when compared to the drug suspension, without any histological alteration. The radioiodinated clozapine ([131I] iodo-CLZ) and radioiodinated optimized formula ([131I] iodo-CLZ-LbPM) were formulated in an excellent radioiodination yield more than 95%. In vivo biodistribution studies of [131I] iodo-CLZ-LbPM showed higher brain uptake (7.8%± 0.1%ID/g) for intranasal administration with rapid onset of action (at 0.25 h) than the intravenous formula. Its pharmacokinetic behavior showed relative bioavailability, direct transport percentage from nose to brain and drug targeting efficiency of 170.59%, 83.42% and 117% respectively. Conclusion: The intranasal self-assembling lecithin based mixed polymeric micelles could be an encouraging way for CLZ brain targeting.


Assuntos
Clozapina , Micelas , Radioisótopos do Iodo , Clozapina/metabolismo , Lecitinas , Distribuição Tecidual , Sistemas de Liberação de Medicamentos/métodos , Administração Intranasal , Encéfalo , Mucosa Nasal/metabolismo , Polímeros/química , Tamanho da Partícula , Portadores de Fármacos/química
18.
Drug Deliv Transl Res ; 13(9): 2340-2352, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36940079

RESUMO

The solid dispersion technique is the most effective and widely used approach for increasing the solubility and release of drugs that have low water solubility. Mirtazapine (MRT) is an atypical antidepressant used to treat severe depression. MRT has a low oral bioavailability (about 50%) due to its low water solubility (BCS class II). The study's goal was to determine optimum conditions for incorporating MRT into various polymer types utilizing the solid dispersion (SD) technique, with the goal of selecting the most suitable formula with the optimal aqueous solubility, loading efficiency, and dissolution rate. The D-optimal design was used to pick the optimal response. The optimum formula was subjected to physicochemical evaluation by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), and scanning electron microscopy (SEM). In vivo bioavailability study was conducted on white rabbits' plasma samples. MRT-SDs were prepared by the solvent evaporation method using Eudragit (RL-100, RS-100, E-100, L-100-55), PVP K-30, and PEG 4000 with different drug/polymer percentages (33.33%, 49.99%, and 66.66%). Results showed that the optimum formula obtained using PVP K-30 at a drug percentage of 33.33% gave a loading efficiency of 100.93%, an aqueous solubility of 0.145 mg/ml, and a dissolution rate of 98.12% after 30 min. These findings demonstrated promising enhancement of MRT properties and increasing its oral bioavailability by 1.34-fold more than plain drug.


Assuntos
Química Farmacêutica , Polímeros , Animais , Coelhos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Mirtazapina , Química Farmacêutica/métodos , Disponibilidade Biológica , Polímeros/química , Povidona/química , Difração de Raios X , Solubilidade , Água , Varredura Diferencial de Calorimetria , Portadores de Fármacos/química
19.
Int J Biol Macromol ; 235: 123571, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36750168

RESUMO

Carbohydrate polymers (polysaccharides) and their derivatives are widely utilized in sustainable corrosion inhibition (SCI) because of their various fascinating properties including multiple adsorption sites, high solubility and high efficiency. Contrary to traditional synthetic polymer-based corrosion inhibitors, polysaccharides are related to the 4E dimension, which stands for Energy, Economy, Ecology, and Effectivity. Furthermore, they are relatively more environmentally benign, biodegradable, and non-bioaccumulative. The current review describes the SCI features of various heteropolysaccharides, including gum Arabic (GA), glycosaminoglycans (chondroitin-4-sulfate (CS), hyaluronic acid (HA), heparin, etc.), pectin, alginates, and agar for the first time. They demonstrate impressive anticorrosive activity for different metals and alloys in a variety of corrosive electrolytes. Through their adsorption at the metal/electrolyte interface, heteropolysaccharides function by producing a corrosion-protective film. In general, their adsorption follows the Langmuir isotherm model. In their molecular structures, heteropolysaccharides contain several polar functional groups like -OH, -NH2, -COCH3, -CH2OH, cyclic and bridging O, -CH2SO3H, -SO3OH, -COOH, -NHCOCH3, -OHOR, etc. that serve as adsorption centers when they bind to metallic surfaces.


Assuntos
Ligas , Metais , Corrosão , Ligas/química , Metais/química , Polissacarídeos , Polímeros/química , Pectinas
20.
Int J Mol Sci ; 24(4)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36835080

RESUMO

The bioactivity of the versatile biodegradable biopolymer poly(lactic acid) (PLA) can be obtained by combining it with natural or synthetic compounds. This paper deals with the preparation of bioactive formulations involving the melt processing of PLA loaded with a medicinal plant (sage) and an edible oil (coconut oil), together with an organomodifed montmorillonite nanoclay, and an assessment of the resulting structural, surface, morphological, mechanical, and biological properties of the biocomposites. By modulating the components, the prepared biocomposites show flexibility, both antioxidant and antimicrobial activity, as well as a high degree of cytocompatibility, being capable to induce the cell adherence and proliferation on their surface. Overall, the obtained results suggest that the developed PLA-based biocomposites could potentially be used as bioactive materials in medical applications.


Assuntos
Ácido Láctico , Polímeros , Polímeros/química , Óleo de Coco , Ácido Láctico/química , Poliésteres/química
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