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1.
Int J Nanomedicine ; 16: 651-665, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33536753

RESUMEN

Objective: This study was intended to utilize lecithin-based mixed polymeric micelles (lbMPMs) for enhancing the solubility and bioavailability of honokiol and magnolol to resolve the hindrance of their extreme hydrophobicity on the clinical applications. Methods: Lecithin was selected to increase the volume of the core of lbMPMs, thereby providing a greater solubilization capacity. A series of amphiphilic polymers (sodium deoxycholate [NaDOC], Cremophor®, and Pluronic® series) were included with lecithin for screening and optimization. Results: After preliminary evaluation and subsequentially optimization, two lbMPMs formulations composed of honokiol/magnolol:lecithin:NaDOC (lbMPMs[NaDOC]) and honokiol/magnolol:lecithin:PP123 (lbMPMs[PP123]) in respective ratios of 6:2:5 and 1:1:10 were optimally obtained with the mean particle sizes of 80-150 nm, encapsulation efficacy (EEs) of >90%, and drug loading (DL) of >9.0%. These lbMPMs efficiently stabilized honokiol/magnolol in phosphate-buffered saline (PBS) at room temperature or 4 °C and in fetal bovine serum or PBS at 37 °C. PK study demonstrated that lbMPMs[NaDOC] showed much improvement in enhancing bioavailability than that by lbMPMs[PP123] for both honokiol and magnolol. The absolute bioavailability for honokiol and magnolol after intravenous administration of lbMPMs[NaDOC] exhibited 0.93- and 3.4-fold increases, respectively, compared to that of free honokiol and magnolol. For oral administration with lbMPMs[NaDOC], the absolute bioavailability of honokiol was 4.8%, and the absolute and relative bioavailability of magnolol were 20.1% and 2.9-fold increase, respectively. Conclusion: Overall, honokiol/magnolol loaded in lbMPMs[NaDOC] showed an improvement of solubility with suitable physical characteristics leading to enhance honokiol and magnolol bioavailability and facilitating their wider application as therapeutic agents for treating human disorders.


Asunto(s)
Compuestos de Bifenilo/farmacología , Lecitinas/química , Lignanos/farmacología , Micelas , Polímeros/química , Administración Oral , Animales , Disponibilidad Biológica , Compuestos de Bifenilo/sangre , Compuestos de Bifenilo/química , Compuestos de Bifenilo/farmacocinética , Liberación de Fármacos , Humanos , Lignanos/sangre , Lignanos/química , Lignanos/farmacocinética , Masculino , Tamaño de la Partícula , Ratas Sprague-Dawley , Solubilidad
2.
Int J Nanomedicine ; 16: 715-724, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33542626

RESUMEN

Objective: The coronavirus disease (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is now rapidly spreading globally. Serological tests are an important method to assist in the diagnosis of COVID-19, used for epidemiological investigations. In this study, we aimed to investigate the impact of different types of vacuum collection tubes on the detection of SARS-CoV-2 IgM and IgG antibodies, using the colloidal gold immunochromatographic assay (GICA). Patients and Methods: A total of 112 patients with COVID-19 and 200 healthy control subjects with no infection were enrolled in this study. Their serum and plasma were collected into four different types of vacuum blood collection tubes. SARS-CoV-2 IgM and IgG specific antibodies in the plasma and serum were then detected by GICA and chemiluminescence assay (CA), respectively. In addition, the particle sizes of different colloidal gold solutions in the presence of different anticoagulants and coagulants were evaluated by both laser diffraction (Malvern) and confocal laser microscope, respectively. Results: Our results revealed that anticoagulated plasma with EDTA-K2 improved the positive detection rate of SARS-CoV-2 IgM antibodies. Furthermore, our results shown that the detection results by GICA and CA were highly consistent, especially, the results of EDTA-K2 anticoagulated plasma detected by GICA was more consistent with CA results. We confirmed that EDTA-K2 could improve the detection sensitivity of SARS-CoV-2 IgG antibodies by chelating excessive colloidal gold compared with sodium citrate or lithium heparin, these methodologies did not appear to cause false positives. Colloidal gold particles could be chelated and aggregated by EDTA-K2, but not by sodium citrate, lithium heparin and coagulants. Conclusion: GICA is widely used to detect antibodies for the advantages of convenient, fast, low cost, suitable for screening large sample and require minimal equipment. In this study, we found that EDTA-K2 amplified the positive antibody signal by chelating colloidal gold and improved the detection sensitivity of SARS-CoV-2 IgM and IgG antibodies when using the GICA. Therefore, we suggested that EDTA-K2 anticoagulated plasma was more suitable for the detection of SARS-CoV-2 antibodies.


Asunto(s)
Anticuerpos Antivirales/aislamiento & purificación , Quelantes/química , Ácido Edético/química , Oro Coloide/química , Inmunoensayo/métodos , Inmunoglobulina G/aislamiento & purificación , Inmunoglobulina M/aislamiento & purificación , /inmunología , Adulto , Anticuerpos Antivirales/sangre , Especificidad de Anticuerpos/inmunología , /inmunología , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Peso Molecular , Tamaño de la Partícula , Polímeros/química , Sensibilidad y Especificidad
3.
Trials ; 22(1): 127, 2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33568226

RESUMEN

OBJECTIVES: The objective of the study is to measure the efficacy of ionic-iodine polymer complex [1] for clinical and radiological improvement in coronavirus disease 2019 (COVID-19) patients. TRIAL DESIGN: The trial will be closed label, randomized and placebo-controlled with a 1:1:1:1 allocation ratio and superiority framework. PARTICIPANTS: All PCR confirmed COVID-19 adult patients including non-pregnant females, with mild to moderate disease, will be enrolled from Shaikh Zayed Post-Graduate Medical Complex, Ali Clinic and Doctors Lounge in Lahore (Pakistan). Patients with any pre-existing chronic illness will be excluded from the study. INTERVENTION AND COMPARATOR: In this multi-armed study ionic-iodine polymer complex with 200 mg of elemental iodine will be given using three formulations to evaluate efficacy. Patients will be receiving either encapsulated iodine complex of 200 mg (arm A), iodine complex syrup form 40 ml (arm B), iodine complex throat spray of 2 puffs (arm C) or empty capsule (arm D) as placebo; all three times a day. All the 4 arms will be receiving standard care as per version 3.0 of the clinical management guidelines for COVID-19 established by the Ministry of National Health Services of Pakistan. MAIN OUTCOMES: Primary outcomes will be viral clearance with radiological and clinical improvement. SARS-CoV-2 RT-PCR and HRCT chest scans will be done on the admission day and then after every fourth day for 12 days or till the symptoms are resolved. RT-PCR will only be shown as positive or negative while HRCT chest scoring will be done depending on the area and severity of lung involvement [2]. Time taken for the alleviation of symptoms will be calculated by the number of days the patient remained symptomatic. 30-day mortality will be considered as a secondary outcome. RANDOMISATION: Stratification for initial COVID-19 status (or days from initial symptoms as a proxy), age groups, gender, baseline severity of symptoms and co-morbidities will be used to ensure that the study arms remain balanced in size for the 1:1:1:1 allocation ratio. Randomization will be done using the lottery method. As patients are being admitted at different times, they will be recruited after obtaining their voluntary written informed consent following all standard protocols of the infection, control and disinfection. BLINDING (MASKING): This is a quadruple (participants, care providers, investigators and outcomes assessors) blinded study where only the study's Primary Investigator will have information about the arms and their interventions. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): 200 patients will be randomized into four groups with three experimental and one placebo arm. TRIAL STATUS: Protocol Version Number is 2.3 and it is approved from IRB Shaikh Zayed Hospital with ID SZMC/IRB/Internal0056/2020 on July 14th, 2020. The recruitment is in progress. It was started on July 30, 2020, and the estimated end date for the trial is August 15, 2021. TRIAL REGISTRATION: Clinical Trial has been retrospectively registered on www.clinicaltrials.gov with registration ID NCT04473261 dated July 16, 2020. FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). With the intention of expediting dissemination of this trial, the conventional formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines.


Asunto(s)
/tratamiento farmacológico , Compuestos de Yodo/administración & dosificación , Polímeros/administración & dosificación , Índice de Severidad de la Enfermedad , Adulto , /mortalidad , Cápsulas , Femenino , Humanos , Masculino , Vaporizadores Orales , Pakistán/epidemiología , Admisión del Paciente , Ensayos Clínicos Controlados Aleatorios como Asunto , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Resultado del Tratamiento
4.
Zhonghua Xin Xue Guan Bing Za Zhi ; 49(2): 121-127, 2021 Feb 24.
Artículo en Chino | MEDLINE | ID: mdl-33611897

RESUMEN

Objective: To evaluate the five-year safety and efficacy of the second generation biodegradable polymer sirolimus-eluting stent (EXCROSSAL) in treating patients with de novo coronary artery diseases. Methods: Patients with coronary artery disease (CAD)who were implanted with EXTROSSAL stents in CREDIT Ⅱ and CREDIT Ⅲ study were included. CREDIT Ⅱ was a randomized trial, and CREDIT Ⅲ was a single-arm study. From November 2013 to December 2014, 833 CAD patients with de novo coronary lesions implanted with EXTROSSAL stents were selected from 33 centers in China. The primary outcome was 5-year target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction and clinically indicated target lesion revascularization. Secondary endpoints was patient-oriented composite endpoint (PoCE), including all-cause death, all myocardial infarction, or any revascularization within 5 years post stenting and stent thrombosis according to Academic Research Consortium's (ARC) definition. Kaplan Meier method was used to calculate the incidence of TLF and PoCE within 5 years after operation. Univariate Cox regression analysis was used to analyze the impacts of diabetes, small vessel disease (vessel diameter ≤ 2.74 mm), lesion length ≥ 16.7 mm and multivessel disease on the incidence of TLF within 5 years after operation. Results: A total of 833 patients were included in this study including 579 males (69.5%), the age was (59.3±9.1) years. And 832 (99.9%) patients completed 5-year clinical follow-up. The incidence of TLF and PoCE in the 5-year follow-up were 10.6%(86/811) and 15.5%(126/811), respectively. Stent thrombosis occurred in 1.0%(8/811) of patients. Univariate Cox regression analysis showed that vessel diameter ≤ 2.74 mm (HR=3.20,95%CI 1.90-5.39,P<0.001), lesion length ≥ 16.7 mm (HR=1.88,95%CI 1.18-2.99,P=0.007) and multivessel disease (HR=2.44,95%CI 1.60-3.72,P<0.001) were related factors of TLF within 5 years after operation. Conclusion: EXCROSSAL stent is effective and safe in treating CAD patients with de novo coronary lesions, with low incidence of TLF and PoCE within 5 years after operation.


Asunto(s)
Fármacos Cardiovasculares , Enfermedad de la Arteria Coronaria , Stents Liberadores de Fármacos , Intervención Coronaria Percutánea , Anciano , China , Enfermedad de la Arteria Coronaria/cirugía , Humanos , Masculino , Persona de Mediana Edad , Polímeros , Factores de Riesgo , Sirolimus/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento
5.
Water Sci Technol ; 83(4): 886-893, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33617495

RESUMEN

Solid-phase denitrification is a promising approach to enhance nitrate removal. In this work, polybutylene succinate (PBS) and peanut shell (PS) (with crosslinked polyvinyl alcohol-sodium alginate (PVA-SA) as carrier) were used to prepare a composite solid carbon source (3P) to denitrify the secondary effluent. The results showed that for carbon release performance, 3P had not only a large release of organics, like PS, but also the excellent sustainability of PBS. Among the short chain fatty acids released by PBS, PS, PVA-SA and 3P, the percentages of acetic acid were 59.42%, 72.54%, 72.29% and 92.11%, respectively. When 3P was used as external carbon source, denitrification performance could be enhanced with effluent dissolved organic carbon lower than 20 mg/L. The prepared 3P could improve denitrification, from both microbial and kinetic aspects. The relative abundance of Gammaproteobacteria increased from 39.32% to 43.58%, and the half saturation constant of the fitting Monod equation was 21.28 mg/L. The prepared 3P is an ideal carbon source for secondary effluent denitrification. Using multiple crosslinking methods to produce carrier is an effective way to show the properties of each material.


Asunto(s)
Carbono , Desnitrificación , Reactores Biológicos , Nitratos , Nitrógeno , Polímeros
6.
Talanta ; 225: 121977, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33592725

RESUMEN

SARS-COV-2 is a novel coronavirus discovered in Wuhan in December 30, 2019, and is a family of SARS-COV (severe acute respiratory syndrome coronavirus), that is, coronavirus family. After infection with SARS-COV-2, patients often experience fever, cough, gas prostration, dyspnea and other symptoms, which can lead to severe acute respiratory syndrome (SARS), kidney failure and even death. The SARS-COV-2 virus is particularly infectious and has led to a global infection crisis, with an explosion in the number of infections. Therefore, rapid and accurate detection of the virus plays a vital role. At present, many detection methods are limited in their wide application due to their defects such as high preparation cost, poor stability and complex operation process. Moreover, some methods need to be operated by professional medical staff, which can easily lead to infection. In order to overcome these problems, a Surface molecular imprinting technology (SM-MIT) is proposed for the first time to detect SARS-COV-2 virus. For this SM-MIT method, this review provides detailed detection principles and steps. In addition, this method not only has the advantages of low cost, high stability and good specificity, but also can detect whether it is infected at designated points. Therefore, we think SM-MIT may have great potential in the detection of SARS-COV-2 virus.


Asunto(s)
/diagnóstico , Nanopartículas de Magnetita/química , Impresión Molecular , Polímeros/química , Proteínas Virales/metabolismo , /virología , Humanos , Microesferas , Ovalbúmina/química , Ovalbúmina/metabolismo , Sensibilidad y Especificidad , Proteínas Virales/química
7.
Biomed Res Int ; 2021: 6653967, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33521128

RESUMEN

3D printing technology is widely used in the field of implantable medical device in recent decades because of its advantages in high precision, complex structure, and high material utilization. Based on the characteristics of 3D printing technology, this paper reviews the manufacturing process, materials, and some typical products of 3D printing implantable medical devices and analyzes and summarizes the development trend of 3D printed implantable medical devices.


Asunto(s)
Impresión Tridimensional , Prótesis e Implantes , Diseño de Prótesis/métodos , Tecnología Farmacéutica/métodos , Materiales Biocompatibles , Prótesis Vascular , Cerámica , Humanos , Prótesis Articulares , Rayos Láser , Ortopedia , Polímeros/química , Stents
8.
Nat Commun ; 12(1): 742, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33531498

RESUMEN

Nanomedicine in combination with immunotherapy offers opportunities to treat cancer in a safe and effective manner; however, remote control of immune response with spatiotemporal precision remains challenging. We herein report a photothermally activatable polymeric pro-nanoagonist (APNA) that is specifically regulated by deep-tissue-penetrating second near-infrared (NIR-II) light for combinational photothermal immunotherapy. APNA is constructed from covalent conjugation of an immunostimulant onto a NIR-II semiconducting transducer through a labile thermo-responsive linker. Upon NIR-II photoirradiation, APNA mediates photothermal effect, which not only triggers tumor ablation and immunogenic cell death but also initiates the cleavage of thermolabile linker to liberate caged agonist for in-situ immune activation in deep solid tumor (8 mm). Such controlled immune regulation potentiates systemic antitumor immunity, leading to promoted cytotoxic T lymphocytes and helper T cell infiltration in distal tumor, lung and liver to inhibit cancer metastasis. Thereby, the present work illustrates a generic strategy to prepare pro-immunostimulants for spatiotemporal regulation of cancer nano-immunotherapy.


Asunto(s)
Inmunoterapia/métodos , Neoplasias/terapia , Polímeros/química , Animales , Sistemas de Liberación de Medicamentos/métodos , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Nanotecnología , Análisis Espacio-Temporal , Linfocitos T Citotóxicos
9.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(1): 57-61, 2021 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-33522178

RESUMEN

Polymer hydrophilic lubricating coatings for medical catheters refer to highly hydrophilic coating films fixed on the surface of catheters with binding force, which can reduce the surface friction with human tissues during the use of interventional catheters, improve the patient comfort of and effectively reduce the incidence of infection. Based on the development process of medical catheter coating, this review summarizes recent advances in the field of polymer hydrophilic lubricating coatings for medical catheters from types of hydrophilic coating polymer, development of coating technology and establishment of coating performance evaluation method. Main problems in this field are analyzed and development trends in the future are prospected.


Asunto(s)
Catéteres , Polímeros , Humanos , Interacciones Hidrofóbicas e Hidrofílicas
10.
Int J Nanomedicine ; 16: 185-199, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33447034

RESUMEN

Background: Therapy for glioblastoma (GBM) has always been very challenging, not only because of the presence of the blood-brain barrier (BBB) but also due to susceptibility to drug resistance. Recently, the clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (CRISPR/Cas9) has revolutionized gene editing technology and is capable of treating a variety of genetic diseases, including human tumors, but there is a lack of safe and effective targeting delivery systems in vivo, especially in the central nervous system (CNS). Methods: Lipid-polymer hybrid nanoparticles (LPHNs-cRGD) were constructed for efficient and targeting delivery of CRISPR/Cas9 plasmids targeting O6-methylguanine-DNA methyltransferase (MGMT), a drug-resistance gene to temozolomide (TMZ). Focused ultrasound (FUS)-microbubbles (MBs) were used to non-invasively and locally open the BBB to further facilitate gene delivery into glioblastoma in vivo. The gene editing efficiency and drug sensitivity changes were evaluated both in vitro and in vivo. Results: The gene-loaded LPHNs-cRGD were successfully synthesized and could protect pCas9/MGMT from enzyme degradation. LPHNs-cRGD could target GBM cells and mediate the transfection of pCas9/MGMT to downregulate the expression of MGMT, resulting in an increased sensitivity of GBM cells to TMZ. MBs-LPHNs-cRGD complexes could safely and locally increase the permeability of the BBB with FUS irradiation in vivo and facilitated the accumulation of nanoparticles at the tumor region in orthotopic tumor-bearing mice. Furthermore, the FUS-assisted MBs-LPHNspCas9/MGMT-cRGD enhanced the therapeutic effects of TMZ in glioblastoma, inhibited tumor growth, and prolonged survival of tumor-bearing mice, with a high level of biosafety. Conclusion: In this work, we constructed LPHNs-cRGD for targeting delivery of the CRISPR/Cas9 system, in combination with FUS-MBs to open the BBB. The MBs-LPHNs-cRGD delivery system could be a potential alternative for efficient targeting gene delivery for the treatment of glioblastoma.


Asunto(s)
Neoplasias Encefálicas/terapia , Resistencia a Antineoplásicos , Terapia Genética , Glioblastoma/terapia , Ultrasonido Enfocado de Alta Intensidad de Ablación , Lípidos/química , Nanopartículas/química , Polímeros/química , Animales , Barrera Hematoencefálica/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Línea Celular Tumoral , Desoxirribonucleasa I/metabolismo , Glioblastoma/tratamiento farmacológico , Humanos , Ratones Endogámicos NOD , Ratones SCID , Microburbujas , Nanopartículas/ultraestructura , Péptidos Cíclicos/química , Plásmidos/genética , Temozolomida/farmacología , Temozolomida/uso terapéutico , Distribución Tisular , Transfección
11.
Ecotoxicol Environ Saf ; 208: 111729, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396060

RESUMEN

In this work, carboxyl-functionalized hollow polymer microspheres (CHPMs) was successfully fabricated using poly (styrene-itaconic anhydride) particles as the core template and itaconic anhydride and trans-anethole cross-linked with divinylbenzene as the shell. The desirable microspheres and hollow structure of CHPMs were demonstrated by scanning and transmission electron microscopies, respectively. The characterized CHPMs as an adsorbent was packed into a solid phase extraction column to simultaneously detect the V(V), Cr(III), Cu(II), Cd(II), and Pb(II) in digested food samples by inductively coupled plasma-mass spectrometry (ICP-MS). A series of experimental parameters of solid-phase extraction (SPE) were investigated through vast experiments to improve sensitivity of the proposed method in metal ions detection. The detection limits of the method reached 0.8-3.2 ng L-1 for the target elements, and the relative standard deviations (RSDs) ranging from 1.2% to 3.5% were obtained from eleven parallel experiments using a 1.0 µg L-1 sample solution. The stability allowed the material to withstand more than 15 cycling while the recoveries remained above 88%. In food samples, the detection limits were at 0.20-0.80 µg kg-1, and satisfactory recoveries of 85-104% were obtained in spike tests of laver, fish as well as chicken.


Asunto(s)
Análisis de los Alimentos/métodos , Extracción en Fase Sólida/métodos , Oligoelementos/análisis , Concentración de Iones de Hidrógeno , Microesferas , Polímeros/química , Análisis Espectral
12.
Water Sci Technol ; 83(1): 198-211, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33460418

RESUMEN

Blended organic copolymer (or homopolymer) and inorganic nanoparticles have been widely used (separately or simultaneously) for optimizing membrane pore structure and surface functionality. However, the prepared membranes suffer from degraded stability and insufficient integrity due to the high solubility or incompatibility of the blending additives. In this work, an organic-inorganic nanocomposite (i.e., PLA-TiO2) was designed, and employed for PSF membrane preparation. The Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis confirmed that bidentate chelating dominated the bonding mechanism between PLA and TiO2. The resultant PSF/PLA-TiO2 membranes possessed a highly porous surface with narrowed pore size distribution, demonstrating the strong pore forming ability of PLA-TiO2 for membrane preparations. Moreover, owing to the distinct inorganic-organic molecular conformation, the PLA-TiO2 exhibited enhanced stability and dispersibility within the PSF substance, which endowed the membrane with long-acting hydrophilicity and UV responsiveness. Given the UV responsiveness that is introduced by PLA-TiO2, UV-assisted strategies (UV-F and UV-C) were designed to further mitigate membrane fouling. The fouling analysis indicated that both reversible fouling and irreversible fouling were reduced in the UV-C process, signifying the synergistic effect between photocatalysis and hydraulics in membrane fouling mitigation. The enhanced membrane performance and the efficient preparation process highlight the potential of PLA-TiO2 in membrane modifications.


Asunto(s)
Nanocompuestos , Polímeros , Poliésteres , Sulfonas , Titanio
13.
J Chromatogr A ; 1638: 461865, 2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33453656

RESUMEN

The strategy of using polymer-grafted media is effective to create protein chromatography of high capacity and uptake rate, giving rise to an excellent performance in high-throughput protein separation due to its high dynamic binding capacity. Taking the scientific development and technological innovation of protein chromatography as the objective, this review is devoted to an overview of polymer-grafted media reported in the last five years, including their fabrication routes, protein adsorption and chromatography, mechanisms behind the adsorption behaviors, limitations of polymer-grafted media and chromatographic operation strategies. Particular emphasis is placed on the elaboration and discussion on the behaviors of ion-exchange chromatography (IEC) with polymer-grafted media because IEC is the most suitable chromatographic mode for this kind of media. Recent advances in both the theoretical and experimental investigations on polymer-grafted media are discussed by focusing on their implications to the rational design of novel chromatographic media and mobile phase conditions for the development of high-performance protein chromatography. It is concluded that polymer-grafted media are suitable for development of IEC and mixed-mode chromatography with charged and low hydrophobic ligands, but not for hydrophobic interaction chromatography with high hydrophobic ligands and affinity chromatography with ligands that have single binding site on the protein.


Asunto(s)
Cromatografía por Intercambio Iónico/normas , Cromatografía/tendencias , Polímeros/química , Proteínas/química , Adsorción , Interacciones Hidrofóbicas e Hidrofílicas , Ligandos
14.
J Chromatogr A ; 1638: 461850, 2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33482613

RESUMEN

Herein, commercially available columns employed in hydrophilic interaction chromatography (HILIC) were characterized by determining their ability to selectively distinguish the minute structural differences between small molecules such as nucleosides and xanthines in complex sample matrices. Principal component analysis (PCA) was applied to the data obtained from structurally similar analytes, and the results showed that HILIC columns could generally be classified into two groups: (i) silane-modified columns that were prepared from either native silica particles or silica particles modified with low-molecular-weight silanes and (ii) polymer-modified columns obtained from silica particles functionalized with organic polymers. These two groups could be further subdivided based on the functionalities attached to the respective stationary phases. These results were confirmed via cluster analysis by preparing a dendrogram using the morphology-based selectivity parameters associated with the respective columns. We were able to determine the selectivity of columns for the OH groups, i.e., α(OH) and the prevailing pH conditions (cation- and anion-exchanging natures) on the surface of the respective stationary phases; α(theobromine/theophylline) was employed to obtain a similar two-dimensional plot. This test scheme, in which five compounds were analyze for each column, was helpful for understanding the impact of factors such as the hydrophilicity, degree of hydration, acidity/basicity, or the weak ion-exchange nature of the respective stationary phases on the separation characteristics of new HILIC stationary phases. The selectivity of columns for the CH2 group was also examined. The cation-exchange nature of the HILIC columns significantly influenced native silica columns and some polymer-modified columns. Herein, 45 commercially available HILIC columns were classified according to this method, and the results proved useful for understanding distinct separation characteristics of each HILIC column, enabling improved column selection.


Asunto(s)
Cromatografía , Interacciones Hidrofóbicas e Hidrofílicas , Polímeros/química , Silanos/química , Análisis por Conglomerados , Intercambio Iónico , Nucleósidos/química , Análisis de Componente Principal , Dióxido de Silicio/química
15.
Life Sci ; 267: 118971, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33385406

RESUMEN

AIMS: The study aimed to develop, characterize, and evaluate poly (ɛ-caprolactone) (PCL) based nanoparticles for the sustained release behaviour of cytarabine and to investigate the in vitro anti-cancer influence on KG-1 leukemic cell line. MATERIALS AND METHODS: Nanoprecipitation method was used for the preparation of cytarabine loaded PCL nanoparticles. The developed nanoparticles were characterized for physicochemical properties and the anti-leukemic effect on the KG-1 cell line was evaluated. KEY FINDINGS: A total number of five formulations were prepared with size range from 120.5 ± 1.18 to 341.5 ± 3.02, entrapment efficiency (41.31 ± 0.49 to 62.28 ± 0.39%), spherical morphology, negative zeta potentials, considerable particle size distribution, compatibility between the drug and excipients and thermal stability. X-ray diffraction analysis confirmed the successful incorporation of cytarabine in PCL polymer. In vitro drug release in phosphate buffer saline (pH 7.4) showed initial burst release followed by sustained release up to 48 h. The sustained release behaviour efficiently increased the toxicity of cytarabine-loaded PCL nanoparticles to KG-1 (leukemic) and MCF-7 (breast cancer) cell lines in time dependent manner with lower IC50 values than that of drug solution. The flow cytometry study revealed the better apoptotic activity of cytarabine loaded PCL nanoparticle against treated KG-1 cell line. The western blot analysis confirmed the upregulation of cleaved caspase-3 and downregulation of Bcl-2 protein. SIGNIFICANCE: The experimental results suggest that cytarabine loaded PCL nanoparticles is an efficient carrier to prevent the dose associated toxicity while providing sustained release pattern to ensure maximum anti-cancer influence.


Asunto(s)
Plásticos Biodegradables/química , Citarabina/farmacología , Nanopartículas/química , Plásticos Biodegradables/metabolismo , Plásticos Biodegradables/farmacología , Línea Celular Tumoral , Preparaciones de Acción Retardada/química , Portadores de Fármacos/química , Composición de Medicamentos/métodos , Liberación de Fármacos/fisiología , Humanos , Células MCF-7 , Nanopartículas/uso terapéutico , Tamaño de la Partícula , Poliésteres/química , Polietilenglicoles/química , Polímeros/química
16.
ACS Appl Mater Interfaces ; 13(3): 3512-3520, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33435676

RESUMEN

Near-infrared conjugated polymer nanoparticles (NIR-CPNs) have been widely used in in vivo imaging fields. However, most of them face the aggregation-induced fluorescence quenching (ACQ) dilemma and serious dye leakage behavior, which impedes the long-term monitoring of transplanted cells in vivo. In the present work, a novel strategy of sandwich-type encapsulation of the conjugated polymer interlayer in the crystalline SiO2 core + shell (SSiO2@SPFTBT@CSiO2) is developed, which works well to avoid the ACQ problem by homogeneously dispersing poly((9,9-dioctylfluorene-2,7-diyl)-alt-(4,7-di(thiophene-2-yl)-2,1,3-benzothiadiazole)-5',5″-diyl) (PFTBT) and suppressing intermolecular π-π stacking. Furthermore, the unparalleled nanostructure efficiently stabilizes nanoparticles and successfully achieves long-term biocompatibility without interfering the biological characteristics of stem cells, indicating the potential of SSiO2@SPFTBT@CSiO2 in cell labeling. In addition, the fate of human umbilical cord mesenchymal stem cells (hucMSCs) in a mouse model with acute liver injury was disclosed. We found that the hucMSCs mainly migrated from the lungs to the injured liver and most transplanted hucMSCs were cleared up by the liver at 8 days post-injection. Revelation of the shuttle process and period will benefit in improving the clinical efficacy of hucMSCs, and the sandwich-type encapsulation strategy could also open a new avenue to obtain bright and robust NIR-CPNs for long-term fluorescence imaging.


Asunto(s)
Rastreo Celular/métodos , Células Madre Mesenquimatosas/citología , Nanopartículas/química , Imagen Óptica/métodos , Polímeros/química , Tiofenos/química , Lesión Pulmonar Aguda/diagnóstico por imagen , Lesión Pulmonar Aguda/terapia , Animales , Línea Celular , Humanos , Masculino , Trasplante de Células Madre Mesenquimatosas , Ratones Endogámicos BALB C , Dióxido de Silicio/química , Tiadiazoles/química , Cordón Umbilical/citología
17.
ACS Appl Mater Interfaces ; 13(3): 3591-3604, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33438397

RESUMEN

A reversible switchable on-demand UV-triggered drug delivery system (DDS) based on interpenetrating polymer networks (IPNs) with silicone as the host polymer and spiropyran (SP)-functionalized guest polymer is designed and demonstrated. The photo-responsive IPNs provide a new triggered drug delivery concept as they exploit the change in intermolecular interactions (work of adhesion) among the drug, matrix, and solvent when the incorporated hydrophobic SP moieties transform into the hydrophilic merocyanine form upon light irradiation without degradation and disruption of the DDS. The change in how the copolymer composition (hydrophilicity and content) and the lipophilicity of the drug (log P) affect the release profile was investigated. A thermodynamic model, based on Hansen solubility parameters, was developed to design and optimize the polymer composition of the IPNs to obtain the most efficient light-triggered drug release and suppression of the premature release. The developed IPNs showed excellent result for dopamine, l-dopa, and prednisone with around 90-95% light-triggered release. The model was applied to study the release behavior of drugs with different log P and to estimate if the light-induced hydrophobic-to-hydrophilic switch can overcome the work of adhesion between polymers and drugs and hence the desorption and release of the drugs. To the best of our knowledge, this is the first time that work of adhesion is used for this aim. Comparing the result obtained from the model and experiment shows that the model is useful for evaluating and estimating the release behavior of specific drugs merocyanine, IPN, DDS, and spiropyran.


Asunto(s)
Benzopiranos/química , Preparaciones de Acción Retardada/química , Indoles/química , Nitrocompuestos/química , Polímeros/química , Antiinflamatorios/administración & dosificación , Antiinflamatorios/química , Dopamina/administración & dosificación , Dopamina/química , Dopaminérgicos/administración & dosificación , Dopaminérgicos/química , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/efectos de la radiación , Interacciones Hidrofóbicas e Hidrofílicas , Levodopa/administración & dosificación , Levodopa/química , Prednisona/administración & dosificación , Prednisona/química , Rayos Ultravioleta
18.
ACS Appl Mater Interfaces ; 13(4): 5652-5659, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33478213

RESUMEN

We have previously shown that the upper critical solution temperature-type thermoresponsive ureido polymers such as polyallylurea and poly(2-ureidoethylmethacrylate) derivatives show liquid-liquid phase separation (LLPS), also known as simple coacervation, under physiological conditions below their phase-separation temperatures (Tp). The addition of the polymer-rich coacervate droplets that result from LLPS to a monolayer cell culture induced aggregation of cells into multicellular spheroids. In this study, we prepared a ureido copolymer, poly(vinylamine-co-vinylurea), with azobenzene substituents (Azo-PVU) and demonstrated light-guided assembly and disassembly of LLPS coacervates. Azo-PVUs with Tp values ranging from 10 to 52 °C were prepared by changing the azobenzene content. Ultraviolet light caused a decrease in the Tp of Azo-PVU because of trans-to-cis photoisomerization of the azobenzene and irradiation with visible light increased the Tp. Thus, LLPS of Azo-PVU was reversibly controlled. The coacervate droplets deposited on a dish surface were immediately dissolved by targeted UV irradiation (owing to a decrease in the Tp). Spatially controlled recruitment of proteins on the dish surface was achieved when protein solution was added to the light-patterned surface. Furthermore, the light-guided deposition of coacervates resulted in the spatiotemporal transformation of monolayer cells to aggregates. This light-controlled LLPS will allow the preparation of novel liquid-based materials for biomolecular and cellular engineering.


Asunto(s)
Compuestos Azo/química , Agregación Celular , Polímeros/química , Polivinilos/química , Agregación Celular/efectos de la radiación , Técnicas de Cultivo de Célula , Células HeLa , Humanos , Isomerismo , Transición de Fase/efectos de la radiación , Proteínas/aislamiento & purificación , Temperatura , Rayos Ultravioleta
19.
ACS Appl Mater Interfaces ; 13(4): 5795-5802, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33480669

RESUMEN

A novel ratiometric electrochemical (EC) sensing platform was established for sensitive immunoassay of target cytokeratin 19 fragment 21-1 (CYFRA21-1) biomarker by combining competitive immunoreaction and multisignal output. This immunosensor utilized Ag nanoparticles (NPs)-functionalized urchin-like Fe3O4@polydopamine (u-Fe3O4@PDA-Ag) as a matrix to immobilize CYFRA21-1 antigens and methylene blue (MB)-absorbed Ni3Si2O5(OH)4-Au nanotubes (NTs) to label the anti-CYFRA21-1 (Ab). During the competitive immunoreaction, square wave voltammetric (SWV) current changes of Ag NPs from u-Fe3O4@PDA-Ag indicator and MB from Ni3Si2O5(OH)4-Au/MB indicator are relevant to the dosage of CYFRA21-1-acquired Ni3Si2O5(OH)4-Au/MB/Ab. More importantly, numerous CYFRA21-1 loaded stably on u-Fe3O4@PDA-Ag exhibited strong competitive capacity toward the target-CYFRA21-1 to combine Ni3Si2O5(OH)4-Au/MB/Ab, causing sensitive changes in the ratio of two measured SWV currents. Prominently, "ΔI = ΔIMB + |ΔIAg NPs|" (ΔIMB and |ΔIAg NPs| represents the change values of the oxidation peak currents of MB and Ag NPs, respectively) could be regarded as significantly amplifying the signal response and ultimately improving the sensitivity of CYFRA21-1 detection, from which we derived a wide dynamic range from 500 fg/mL to 50 ng/mL and a low detection limit of 0.39 pg/mL (S/N = 3). This work may exert a profound impact on monitoring other biomarkers in early diagnosis of diseases.


Asunto(s)
Antígenos de Neoplasias/sangre , Óxido Ferrosoférrico/química , Oro/química , Queratina-19/sangre , Azul de Metileno/química , Nanotubos/química , Antígenos de Neoplasias/análisis , Técnicas Electroquímicas/métodos , Humanos , Inmunoensayo/métodos , Indoles/química , Queratina-19/análisis , Límite de Detección , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Nanotubos/ultraestructura , Polímeros/química , Compuestos de Silicona/química , Plata/química
20.
ACS Appl Mater Interfaces ; 13(4): 5486-5497, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33491443

RESUMEN

Flexible paper-based sensors may be applied in numerous fields, but this requires addressing their limitations related to poor thermal and water resistance, which results in low service life. Herein, we report a paper-based composite sensor composed of carboxylic carbon nanotubes (CCNTs) and poly-m-phenyleneisophthalamide (PMIA), fabricated by a facile papermaking process. The CCNT/PMIA composite sensor exhibits an ability to detect pressures generated by various human movements, attributed to the sensor's conductive network and the characteristic "mud-brick" microstructure. The sensor exhibits the capability to monitor human motions, such as bending of finger joints and elbow joints, speaking, blinking, and smiling, as well as temperature variations in the range of 30-90 °C. Such a capability to sensitively detect pressure can be realized at different applied frequencies, gradient sagittas, and multiple twists with a short response time (104 ms) even after being soaked in water, acid, and alkali solutions. Moreover, the sensor demonstrates excellent mechanical properties and hence can be folded up to 6000 times without failure, can bear 5 kg of load without breaking, and can be cycled 2000 times without energy loss, providing a great possibility for a long sensing life. Additionally, the composite sensor shows exceptional Joule heating performance, which can reach 242 °C in less than 15 s even when powered by a low input voltage (25 V). From the perspective of industrialization, low-cost and large-scale roll-to-roll production of the paper-based sensor can be achieved, with a formed length of thousands of meters, showing great potential for future industrial applications as a wearable smart sensor for detecting pressure and temperature, with the capability of electric heating.


Asunto(s)
Nanotubos de Carbono/química , Papel , Fenilendiaminas/química , Ácidos Ftálicos/química , Polímeros/química , Dispositivos Electrónicos Vestibles , Técnicas Biosensibles/instrumentación , Conductividad Eléctrica , Humanos , Monitoreo Fisiológico/instrumentación , Movimiento (Física) , Nanotubos de Carbono/ultraestructura
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