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1.
Lab Med ; 55(2): 209-214, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-37499047

RESUMO

OBJECTIVE: The objective of this study was to assess oxidative stress in small for gestational age (SGA) newborns and their mothers by evaluating intra- and extracellular thiol homeostasis and the quantification of major oxidants and antioxidants. METHODS: A total of 75 mothers and their 75 newborns (43 SGA) were enrolled in this study. Thiol-disulfide homeostasis, serum myeloperoxidase, catalase, total oxidant, and antioxidant status were analyzed. Additionally, erythrocytic glutathione (GSH) homeostasis was measured. RESULTS: Although native and total thiol levels were decreased, disulfide levels were increased in SGA groups. Additionally, myeloperoxidase activity and total oxidant status levels were significantly elevated whereas total antioxidant status levels and enzymatic antioxidant systems were diminished in SGA groups. Similarly, intra-erythrocytic GSH homeostasis was shifted in favor of oxidants in SGA groups. CONCLUSION: Our results demonstrate that insufficient antioxidant systems in mothers and a robust source of oxidative stress in SGA might contribute to the pathophysiology of SGA births.


Assuntos
Antioxidantes , Oxidantes , Humanos , Recém-Nascido , Antioxidantes/metabolismo , Idade Gestacional , Oxirredução , Peroxidase , Dissulfetos , Compostos de Sulfidrila , Biomarcadores
2.
Bioelectrochemistry ; 144: 107993, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34823072

RESUMO

Biotin is widely used in infant formula to prevent biotin deficiency of newborn babies and in beauty products as nutritional supplements for coenzymatic functions and having strong nails, shiny hair, and skin over the last few years. There is a need for the development of a fast, simple and reusable assay method to perform biotin determination at very low concentrations. Biotin determination has achieved with a prepared potentiometric biotin sensor that has a very wide concentration range (10-15M-10-7M) and a lower detection limit (0.3 10-15M) with a very good regression coefficient (0.9925). A quick response (7 min), good accuracy (recovery 100.4-103.7%), reproducible, reusable (10 times), and long-term stability (3 months) have been obtained using the prepared potentiometric sensor. The obtained results have proved that the prepared potentiometric sensor can be used for biotin determination in real samples.


Assuntos
Estreptavidina
3.
Protein Pept Lett ; 28(11): 1303-1311, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34629039

RESUMO

BACKGROUND: Sarcosine, also known as N-methyl glycine, is a natural amino acid that is an intermediate and by product in glycine synthesis and degradation. Recently found in many peptides, sarcosine has been researched as a newly accepted prostate cancer marker. The increased concentration of sarcosine in blood serum and the urine showed that malignancy of measured prostate cancer cells is active. OBJECTIVE: In this article, we aimed to design a potentiometric biosensor for detection of sarcosine with a low detection limit, high selectivity, short response time, wide linear range, and satisfactory long-term stability. METHODS: In this article, we developed a new Graphene oxide (GFOX) photosensitive cross-linker based potentiometric biosensor based on the AmiNoAcid (monomer) Decorated and Light Underpinning Conjugation Approach (ANADOLUCA) method. The functional groups determined using Raman, FT-IR, XPS analyzes, and surface characterization, the morphology of synthesized GFOX photosensitive cross-linker were determined by TEM and AFM studies. Then, the performance of the GFOX based potentiometric biosensor has been evaluated. RESULTS: When the usage of the developed GFOX doped potentiometric biosensor against sarcosine determination, it was found that 10-4 mM sarcosine was determined in 60 seconds in the solution. In addition, the detection limit of the GFOX doped potentiometric biosensor was found to be 9.45x10-7 mM, and the linear potentiometric biosensor was found to be in the concentration range of 10-1 to 10-5 mM. The selectivity studies of the developed potentiometric biosensor were investigated using glycine solutions, and it was determined that GFOX doped potentiometric biosensor was more selective against sarcosine. Besides this, a reusability test using 10-3 mM sarcosine solution showed that reproducible studies were performed without the loss of potential of designed potentiometric biosensor and no loss of sensitivity. CONCLUSION: After applying the framework, we get a new potentiometric biosensor for sarcosine determination. GFOX photosensitive cross-linker was used in designing potentiometric biosensors, and this increased the stability and efficiency of the biosensor. Therefore, the developed potentiometric biosensor for sarcosine determination could be easily used for the early diagnosis of prostate cancer.


Assuntos
Técnicas Biossensoriais , Grafite/química , Sarcosina/análise , Humanos , Masculino , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Sarcosina/sangue
4.
Biotechnol Appl Biochem ; 68(2): 392-403, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32388888

RESUMO

In this study, carbon dioxide (CO2 ) capture and conversion systems based on the combination of biomimetic systems with nano enzymes have been developed. The effectiveness of the developed system has been investigated toward CO2 conversion. For this aim, nano ribulose bisphosphate carboxylase/oxygenase (RuBisCO) enzyme that plays role in the Calvin cycle in photosynthesis has been synthesized in 93 nm size according to AmiNoAcid (monomer) Decorated and Light Underpinning Conjugation Approach (ANADOLUCA) method. Enzymatic activity of synthesized nano RuBisCO enzyme has been spectrophotometrically determined by the formation of 3-phosphoglycerate (3-PGA) at the end of the reaction between CO2 and d-ribulose-1,5 biphosphate with the catalysis of RuBisCO enzyme at 340 nm. The effect of substrate concentration, pH, temperature, and Mg2+ ion concentration on the conversion reaction have investigated comparatively with nano and free RuBisCO enzyme. Besides this, the reusability feature of synthesized nano RuBisCO enzyme in conversion of CO2 reaction is indicated. When all data were evaluated, it has been seen that the nano RuBisCO enzyme is effective on the conversion of CO2 into 3-PGA and can be used for CO2 capture and conversion systems repeatedly without any deformation in its structure.


Assuntos
Dióxido de Carbono/metabolismo , Fotossíntese , Ribulose-Bifosfato Carboxilase/metabolismo , Catálise
5.
Soft Matter ; 17(4): 1008-1015, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33284939

RESUMO

3D bioprinting allows the production of patient-specific tissue constructs with desired structural characteristics such as high resolution, controlled swelling degree, and controlled degradation behavior by mostly using hydrogels. Crosslinking of hydrogels is an essential parameter in bioprinting applications, which is beneficial for tuning structural specifications. In this study, gelatin-alginate-whey protein isolate based hydrogels have been used for 3D printing structures in a layer-by-layer fashion. These structures were cross-linked by the Amino Acid (monomer) Decorated and Light Underpinning Conjugation Approach (ANADOLUCA) method, which is a unique, non-invasive photosensitive cross-linking technique for protein-based mixtures. In that aim, hydrogel properties (e.g., printability, biocompatibility, rheologic and mechanical behavior) and cross-linking properties (e.g., swelling and degradation behavior) were studied. Results were compared with UV and ionic cross-linking techniques, which are the abundantly used techniques in such studies. The results showed that the ANADOLUCA method can be used for in situ cross-linking under mild conditions for the printing of bio-inks, and the proposed method can be used as an alternative for UV-based and chemical cross-linking techniques.


Assuntos
Materiais Biocompatíveis , Bioimpressão , Humanos , Hidrogéis , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais
6.
Biotechnol Appl Biochem ; 68(6): 1153-1158, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32970336

RESUMO

An immunosensor is based on the signal measurement obtained upon the reaction of an antibody antigen complex. It plays a significant role in various fields such as environmental analysis, production monitoring, drug detection or screening, veterinary medicine, and animal food. In this study, an antibody crosslinked graphen oxide (GO)-based potentiometric sensor has been developed for fast, simple, and economical detection of clenbuterol. In this context, the photosensitive amino acid bound GO platform is synthesized and used for the preparation of electrode material. Then, polymeric structure is characterized by infrared spectroscopy, and the performance of immunonano platform prepared by potentiometric sensor is evaluated. The effect of pH, response time, selectivity, and sensitivity is investigated. Under the optimized conditions, a simple and rapid method for the determination of clenbuterol from milk sample is established by immuno-potentiometric sensor. The detection limit has found to be 0.87 × 10-9 mmol L-1 for this immuno-potentiometric sensor. This immuno-potentiometric sensor has optimum pH at 7.0, a wide linear response (1.0 × 10-2 to 1.0 × 10-9 mmol L-1 ), rapid response time (2 Min) and 36 weeks operational lifetime.


Assuntos
Anticorpos/química , Clembuterol/análise , Reagentes de Ligações Cruzadas/química , Grafite/química , Imunoensaio , Potenciometria
7.
J Fluoresc ; 29(3): 609-617, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30963369

RESUMO

This study demonstrates the preparation of photosensitively orientated and crosslinked proteinous polymeric shell having quantum dot based nanocrystals through Amino acid Decorated and Light Underpinning Conjugation Approach (ANADOLUCA). ANADOLUCA is based on photo-electron transfer method and uses these decorated nanocrystals for specifically and effectively recognition and detection of Immunoglobulin M in the aqueous environment. The conjugation method effectively provides an orientation of affinity pairs on the surface of quantum dots nanocrystals. This photosensitive ruthenium-based amino acid monomer is a synthetic and inexpensive material for the preparation of bioconjugates. The nanocrystals give advantages for using a wide pH and temperature range. The construction and preparation method is applicable to silica materials, superparamagnetic particles, quantum dots, carbon nanotubes, Ag/Au nanoparticles, Au surfaces, and polymeric materials. This prepared proteinous polymeric shell decorated nanocrystals are of great potential in applications in life sciences and can be used in infection case studies or allergy symptoms.


Assuntos
Imunoglobulina M/química , Nanopartículas/química , Polímeros/química , Concanavalina A/química , Pontos Quânticos/química , Rutênio/química , Água/química
8.
Talanta ; 176: 85-91, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28917810

RESUMO

In this study, a biomemory device, consisting of hemoglobin (Hb) cross-linked by MACys-Ru(bipyr)2-MACys) photosensitive monomer cross-linkers, which have memory effect through both Ru3+/2+ in hapten monomer and Fe3+/2+ in redox active center of Hb through multi-charge transfer mechanism, has been improved. Cyclic voltammetry (CV) has been used to determine the redox property of the Hb cross-linked MACys-Ru(bipyr)2-MACys) hapten. Three memory functions, writing, reading and erasing of the fabricated biomemory device, have been accomplished by chronoamperometry (CA) and open-circuit potential amperometry (OCPA). The reliability and repeatability of the biodevice consisting of the p(Hb-co-MACys-Ru(bipyr)2-MACys) sextet state bio-memory layer have been analysed. The Hb film based biodevice on gold electrodes has shown ≥ 2 months the retention time and switched until 106 times continuous cycling without degradation in efficiency. Other hand, the topography of p(Hb-co-MACys-Ru(bipyr)2-MACys) layer on the gold surface has investigated by scanning electron microscopy (SEM) and EDX data.


Assuntos
Hemoglobinas/química , Nanoestruturas/química , Sulfato de Amônio/química , Cisteína/análogos & derivados , Cisteína/química , Ouro/química , Haptenos/química , Compostos Organometálicos/química
9.
Chempluschem ; 83(1): 42-46, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31957319

RESUMO

A large-area, all-flexible, microwaveable polydimethoxysilane microfluidic reactor was fabricated by using a 3D printing system. The sacrificial microchannels were printed on polydimethoxysilane substrates by a direct ink writing method using water-soluble Pluronic F-127 ink and then encapsulated between polydimethoxysilane layers. The structure of micron-sized channels was analyzed by optical and electron microscopy techniques. The fabricated flexible microfluidic reactors were utilized for the acetylation of different amines under microwave irradiation to obtain acetamides in shorter reaction times and good yields by flow organic synthesis.

10.
Biosens Bioelectron ; 103: 19-25, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29277010

RESUMO

Ferritin is an iron cage having protein, capable of extracting metal ions in their cages and a consequence of the electron transfer of metal ions in their cage by reduction and oxidation processes, electrochemical information storage devices can be designed. In this work, ferritin based protein biomemory substrate has been synthesized by using Amino Acid (monomer) Decorated and Light Underpinning Conjugation Approach (ANADOLUCA) method, which utilizes photosensitive electron transfer based microemulsion co-polymerization as nanobead form of ferritin. Protein substrate contains metal ions such as silver and copper or metal ion pairs namely, silver-copper (Janus bionanocage) and co-polymeric shell of the photosensitive crosslinker protein. The redox behavior of bionanocages differentiates electrochemical "writing" and "erase" states depending on these metal ions (silver or copper) or metal ion pairs. The bionanocages based biomemory substrates have been immobilized using graphene modified glassy carbon electrodes and the memory functions of ferritin based bionanocages have been confirmed by chronoamperometry (CA) and open circuit potential amperometry (OCPA). The stability and durability of multi-state memory devices represent promising properties for future bioelectronic information technologies.


Assuntos
Aminoácidos/química , Técnicas Biossensoriais , Ferritinas/química , Metais/isolamento & purificação , Cobre/química , Eletrodos , Grafite/química , Ferro/química , Metais/química , Oxirredução , Processamento de Sinais Assistido por Computador , Prata/química
11.
Mater Sci Eng C Mater Biol Appl ; 79: 336-342, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28629026

RESUMO

A multistate biomemory device consisting of cytochrome c (Cyt-c) photosensitively cross-linked by MACys-Ru(bipyr)2-MACys hapten molecules, which have memory effect through a charge transfer mechanism, has been developed. In this study, it has suggested a highly resolute surface-confined switch composed a signal-enhanced electro-active protein (Cyt-c) co-polymerized on the gold substrates that can be controlled by redox property through Ruthenium based cysteine monomer hapten, MACys-Ru(bipyr)2-MACys as an ANADOLUCA photosensitive cross-linker. The photosensitive cross-linking of the Cyt-c protein on the gold surface topography has been determined by the scanning electron microscopy (SEM). Two state memory functions, writing and erasing of the developed biomemory device, have been investigated by the chronoamperometry (CA) and open-circuit potential amperometry (OCPA). The polymeric proteinous memory device, p(MACys-Ru(bipyr)2-MACys-co-Cyt-c) layer, on the gold electrode is stable and repeatable up to with 104 times continuous cycle.


Assuntos
Haptenos/química , Reagentes de Ligações Cruzadas , Citocromos c , Eletrodos , Desenho de Equipamento , Ouro , Oxirredução
12.
Sensors (Basel) ; 17(3)2017 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-28245588

RESUMO

Molecularly imprinted polymers (MIPs) as artificial antibodies have received considerable scientific attention in the past years in the field of (bio)sensors since they have unique features that distinguish them from natural antibodies such as robustness, multiple binding sites, low cost, facile preparation and high stability under extreme operation conditions (higher pH and temperature values, etc.). On the other hand, the Quartz Crystal Microbalance (QCM) is an analytical tool based on the measurement of small mass changes on the sensor surface. QCM sensors are practical and convenient monitoring tools because of their specificity, sensitivity, high accuracy, stability and reproducibility. QCM devices are highly suitable for converting the recognition process achieved using MIP-based memories into a sensor signal. Therefore, the combination of a QCM and MIPs as synthetic receptors enhances the sensitivity through MIP process-based multiplexed binding sites using size, 3D-shape and chemical function having molecular memories of the prepared sensor system toward the target compound to be detected. This review aims to highlight and summarize the recent progress and studies in the field of (bio)sensor systems based on QCMs combined with molecular imprinting technology.


Assuntos
Impressão Molecular , Técnicas Biossensoriais , Polímeros , Quartzo , Técnicas de Microbalança de Cristal de Quartzo , Reprodutibilidade dos Testes , Temperatura
13.
Talanta ; 167: 172-180, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28340708

RESUMO

Cancer antigen 125 (CA 125) is widely used as diagnostic biomarker for ovarian cancer. Change in the concentration level of CA 125 is associated with disease progression or regression. CA 125 posseses a phosphorylation site and protein backbone is phosphorylated on serine, before secretion. In this study, we have developed an imprinting method for CA 125 recognition and determination. In this method, methacryloyl antipyrine europium (III) [(MAAP)2-Eu(III)] and methacryloyl antipyrine terbium (III) [(MAAP)2-Tb(III)] have been used as new metal-chelating monomers via metal coordination-chelation interactions. Phosphoserine (PS) has been used as a template for the detection of CA 125. PS imprinted carbon nanotube (CNT) and Fe2O3 nanoparticle (SPN) have cavities that are selective for CA 125. The binding affinity of the PS imprinted CNT and SPN nanosensor has been investigated using Langmuir adsorption isotherms and affinity constants (Kaffinity) have found to be 1.85 105M-1 for PS and 13.5 10-3 mLU-1 and 7.73 10-3 mLU-1 for CA 125 (for CNT and SPN, respectively). Detection limit of PS imprinted CNT nanosensor for PS and CA 125 have been found to be 1.77 10-10M and 0.49 UmL-1, respectively. Human serum samples have been spiked with different concentrations of CA 125 (in pH 7.4 PBS) to investigate the feasibility of the nanosensors for clinical applications. Experimental results have been revealed that prepared nanosensors have been exhibited better sensivity, recovery and reproducibility.


Assuntos
Antígeno Ca-125/análise , Limite de Detecção , Impressão Molecular , Nanotecnologia/instrumentação , Fosfosserina/química , Metacrilatos/química , Nanotubos de Carbono/química
14.
Mater Sci Eng C Mater Biol Appl ; 69: 231-5, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27612708

RESUMO

In this study, a simple, rapid and sensitive method based on novel molecular imprinted polymeric sensor has been developed and validated for the determination of prostate cancer metabolite biomarker. The molecularly imprinted polymer (MIP) has been synthesized by emulsion polymerization, using sarcosine as template molecule, methacryloylamido histidine (MAH) as functional monomer and ethylene glycol dimethacrylate (EDMA) as cross-linking agent. The performance of the developed sarcosine sensor has been evaluated, and the results have indicated that a sensitive potentiometric sensor has been fabricated. The sarcosine sensor has showed high-selectivity, shorter response time (<2min), wider linear range (10(-2)-10(-6)mM), lower detection limit (1.35×10(-7)mM), and satisfactory long-term stability (>5.5months).


Assuntos
Impressão Molecular , Polímeros/química , Potenciometria , Sarcosina/análise , Biomarcadores Tumorais/análise , Histidina/química , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Reprodutibilidade dos Testes , Sarcosina/química , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Biotechnol Prog ; 31(1): 119-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25376531

RESUMO

As one of the most important components copying DNA molecules in the PCR system, Taq DNA polymerase has a high processivity, however, lower persistence when compared to other polymerases. Studies for the enhancement of stability of Taq DNA polymerase is of great importance. The present study describes the integration of PCR application of cross-linked Taq DNA polymerase enzyme in a nanochamber using a ruthenium based MATyr-Ru-(bipyr)2)-MATyr monomer hapten prepared by photosensitive microemulsion polymerization technique. The conjugation and cross-linking have achieved using our previously invented Aminoacid (monomer) Decorated and Light Underpining Conjugation Approach (ANADOLUCA) method. Microemulsion polymerization media has prepared by dispersing PVA in deionized water. The nano enzyme could be easily prepared at room temperature, in daylight and under nitrogen atmosphere using ruthenium based photosensitive cross-linking agents. The nano copy machine particles (nano Taq DNA polymerase) are very stable against more acidic or more basic conditions, high temperatures and could be reusable in PCR analysis for many times without any deformation in their structures.


Assuntos
Nanoestruturas/química , Nanotecnologia/instrumentação , Reação em Cadeia da Polimerase/instrumentação , Taq Polimerase/química , Taq Polimerase/metabolismo , DNA/química , DNA/metabolismo , Estabilidade Enzimática , Desenho de Equipamento , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Reação em Cadeia da Polimerase/métodos
16.
Biomed Chromatogr ; 28(10): 1345-51, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24827758

RESUMO

In this study, we have investigated the isolation of serum amyloid P (SAP) and C-reactive protein (CRP) from rainbow trout. It has recently been found that SAP is deposited in atherosclerotic lesions or neurofibrillary tangles, which are related to aging process and Alzheimer's disease. Given the importance of CRP, the CRP level in blood is becoming recognized as a potential means of monitoring cardiovascular risk. These two proteins, members of the pentraxin family of oligomeric serum proteins, were isolated from rainbow trout using N-methacryloyl-phosphoserine (MA-pSer) immobilized poly (2-hydroxy ethylmethacrylate) (PHEMA) cryogels as a column material in a fast protein liquid chromatography system. The separation process was verified in two steps. First, SAP and CRP proteins were isolated together from serum sample of rainbow trout using MA-pSer/PHEMA cryogel columns. Second, SAP protein was separated chromatographically from CRP protein using the Ca(2+) ion immobilized PHEMA cryogel column. According to the data, a new and effective technique has been developed for the isolation of SAP and CRP proteins from a biological source, rainbow trout. Finally, purified SAP and CRP were loaded using sodium dodecyl sulfate-polyacrylamide gel and western blot analysis to investigate the purity of chromatographically isolated SAP and CRP compared with commertial SAP and CRP.


Assuntos
Proteína C-Reativa/isolamento & purificação , Cromatografia Líquida de Alta Pressão/instrumentação , Componente Amiloide P Sérico/isolamento & purificação , Adsorção , Animais , Proteína C-Reativa/análise , Proteína C-Reativa/química , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Concentração de Íons de Hidrogênio , Oncorhynchus mykiss , Poli-Hidroxietil Metacrilato/química , Componente Amiloide P Sérico/análise , Componente Amiloide P Sérico/química
17.
Artif Cells Nanomed Biotechnol ; 42(2): 138-45, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24621078

RESUMO

The main problem in cancer chemotherapy is the cytotoxic side effects of therapeutics on healthy tissues and cells. The targeted drug delivery and nanotechnology are intensively investigated area to find new ways to solve, at least to reduce, these problems. Hereby, we have reported a new method inspired from both conventional military strategies and biorecognition in the body. In this respect, we have produced two fluorescent nano-drug systems with bitargeting and biorecognition properties, recognizing cancer cells and each other. The multiplexed nanostructures were interacted with HL-60 cells to show their efficiency for bitargeting, ambushing, timed, and double-controlled cancer cell apoptosis.


Assuntos
Antineoplásicos/farmacologia , Ifosfamida/farmacologia , Leucemia/tratamento farmacológico , Nanoestruturas/química , Pró-Fármacos/farmacologia , Apoptose/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Células HL-60 , Humanos , Leucemia/patologia , NADPH-Ferri-Hemoproteína Redutase/síntese química , Nanopartículas/química , Nanotecnologia/métodos , Transtornos de Fotossensibilidade , Polimerização , Pontos Quânticos/química
18.
Colloids Surf B Biointerfaces ; 112: 1-8, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23928053

RESUMO

In this study, we aimed to develop an alternative matrix able to deplete the albumin (Alb) and immunoglobulin G (IgG) from blood plasma simultaneously to prepare plasma samples for large-scale applications of blood-related proteomics. As a first step, nano-protein A nanoparticles (nanoProA) were prepared and characterized. Subsequently, cibacron blue F3GA (CB) was immobilized onto the nanoProA's to enhance their specific affinity for Alb molecules. Finally, both nanoparticles, specifically, nanoProA and CB-nanoProA, were separately embedded into cryogel structures to combine advantages of the nanoparticles with those of the cryogels. The protein adsorption was optimized using aqueous Alb and IgG solutions separately. Subsequently, competitive protein adsorption was performed using a protein mixture prepared with Alb and IgG adhering to their plasma protein ratios. Because of the CB-immobilization, the Alb depletion performance of the cryogels increased whereas the IgG depleting performance decreased. Using the nanoProA, embedded cryogel removed 99.3% of the IgG, while using the CB-nanoProA embedded cryogel removed 97.5% of the Alb content. The simultaneous depletion performances of the cryogels for Alb and IgG were characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In this study, the monolithic cryogel-based adsorbents were classified as an alternative matrix to prepare plasma samples for proteomics applications at the preparative scale.


Assuntos
Imunoglobulina G/sangue , Imunoglobulina G/isolamento & purificação , Albumina Sérica/isolamento & purificação , Adsorção , Criogéis/química , Humanos , Proteínas Imobilizadas , Nanopartículas/química , Nanopartículas/ultraestrutura , Poli-Hidroxietil Metacrilato , Proteômica/métodos , Proteína Estafilocócica A , Triazinas
19.
Artigo em Inglês | MEDLINE | ID: mdl-23896429

RESUMO

Hyaluronic acid (HA) has been used in many applications such as pharmaceutical, clinical and cosmetics, so its separation and purification is very important. In this study, firstly d-glucuronic acid imprinted polymers (MIPs) have been synthesized for the separation of HA which has glucuronic acid part in its structure. MIP particles have characterized by elemental analysis, Fourier Transform Infrared Spectroscopy (FT-IR) and swelling tests. Then, synthesized MIP particles have embedded into polyacrylamide based cryogel. Cryogel has prepared by free radical cryogelation process initiated by N,N,N',N'-Tetramethylethylenediamine (TEMED) and ammonium persulfate (APS) as redox initiators. This cryogel material was characterized by FT-IR, swelling tests, scanning electron microscopy (SEM) and surface adsorption analyze including pore size analyzer (BET) method. The adsorption of HA has investigated by spectrophotometric method using MIPs embedded into cryogel columns (GAIPEC) and the maximum HA adsorption capacity was found to be 318mgg(-1). The selectivity of GAIPEC column has estimated using N-acetylglucose amine as interfering agent since this molecule is a part of HA and the results have shown that GAIPEC has been nearly 35 times selective for HA than N-acetylglucose amine. The optimum chromatographic conditions for separation of HA were investigated. pH 7.0 buffer solution for elution and 0.1M of NaCl solution as desorption agent were used at 0.5mLmin(-1) flow rate. Also, recovery of GAIPEC was investigated and the results have shown that GAIPEC could be used many times without decreasing its adsorption capacity significantly. Here in, combining selectivity of MIP particles and mechanical properties of cryogel, a rigid and stable material was prepared for the separation and purification of HA. To point out this, HA has been isolated from fish eye and fermentation of Streptococcus equi RSKK 679 cell culture. After that, it has characterized and Fast Protein Liquid Chromatography (FPLC) applications have been investigated.


Assuntos
Cromatografia Líquida/métodos , Criogéis/química , Ácido Glucurônico/química , Ácido Hialurônico/isolamento & purificação , Polímeros/química , Adsorção , Cromatografia Líquida/instrumentação , Ácido Hialurônico/química , Impressão Molecular , Polímeros/síntese química
20.
Mater Sci Eng C Mater Biol Appl ; 33(4): 1900-6, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23498211

RESUMO

α-Amylase (EC 3.2.1.1; α-D-1,4,glucan glucanohydrolase) catalyzes the hydrolysis of α-D-(1,4)-glucosidic linkages in starch, glycogen, and various malto-oligosaccharides, by releasing α-anomeric products. In this study, a novel method has been developed to prepare nanoprotein particles that carry α-amylase as a monomer by using a photosensitive microemulsion polymerization process. The nanostructured α-amylase with photosensitive features have been characterized by fluorescence spectroscopy, transmission electron microscopy (TEM) and Zeta Sizer. The fluorescence intensity of amylase nanoparticles was determined to be 658 a.u. at 610 nm and the average particle size of nanoamylase was found to be about 71.8 nm. Both free α-amylase and nanoparticles were used in the hydrolysis of starch under varying reaction conditions such as pH and temperature that affect enzyme activity and the results were compared to each other. Km values were 0.26 and 0.87 mM and Vmax values were 0.36 IU mg(-1) and 22.32 IU mg(-1) for nanoenzyme and free enzyme, respectively. Then, thermal stability, storage stability and reusability were investigated and according to the results, activity was preserved 60% at 60 °C; 20% at 70-80 °C temperature values and 80% after 105 days storage. Finally after 10 cycles, the activity was preserved 90% and this novel enzymatic polymeric amylase nanoparticle has showed considerable potential as reusable catalyst.


Assuntos
Biopolímeros/química , Nanopartículas/química , Amido/metabolismo , alfa-Amilases/química , alfa-Amilases/metabolismo , Animais , Bacillus/enzimologia , Bioensaio , Bovinos , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Nanopartículas/ultraestrutura , Tamanho da Partícula , Reciclagem , Espectrometria de Fluorescência , Temperatura
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