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1.
Anal Chem ; 93(36): 12434-12440, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34473470

RESUMO

The ability to accurately diagnose cancer is the cornerstone of early cancer treatment. The mitochondria in cancer cells maintain a higher pH and lower polarity relative to that in normal cells. A probe that reports signals only when both conditions are met may provide a reliable method for cancer detection with reduced false positives. Here, we construct an AND logic gate fluorescent probe using mitochondrial microenvironments as inputs. Utilizing the hydrolysis of a coumarin scaffold, the probe generates fluorescence signals ("ON") only when high pH (>7.0) and low polarity conditions exist simultaneously. Additionally, the higher mitochondrial membrane potential in cancer cells provides an additional level of selectivity because probe has increased affinity for cancer cell mitochondria. These capabilities endow the probe with a high contrast fluorescence diagnosis ability of cancer at cellular and tissue levels (as high as 51.9 fold), which is far exceeding the clinic threshold of 2.0 fold.


Assuntos
Lógica , Neoplasias , Cumarínicos , Fluorescência , Corantes Fluorescentes , Hidrólise , Neoplasias/diagnóstico
2.
Org Biomol Chem ; 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34590107

RESUMO

A general visible-light-promoted metal-free synthesis of secondary and tertiary thiocarbamates starting from thiosulfonates and N-substituted formamides is developed. By employing rhodamine B as a photocatalyst and tert-butyl hydroperoxide (TBHP) as an oxidant, a wide scope of thiocarbamates can be obtained through direct thiolation of acyl C-H bonds under irradiation of blue light at room temperature for 12 h.

3.
ACS Appl Mater Interfaces ; 13(37): 44086-44095, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34516075

RESUMO

Lipid droplets (LDs) play indispensable roles in numerous physiological processes; hence, the visualization of the dynamic behavior of LDs in living cells is of great importance in physiological and pathological research. In this article, the quantitative structure-activity relationship (QSAR) theory was employed as an effective design strategy for the development of organelle-targeting carbon dots (CDs). The lipid-water partition coefficient (Log P) of the QSAR was adopted as a key parameter to predict the cellular uptake and subcellular localization of CDs in live cells. By carefully adjusting the molecular structure and lipophilicity of the precursors, p-phenylenediamine-derivatized nucleolus-targeting hydrophilic CDs were converted to lipophilic CDs [4-piperidinoaniline (PA) CDs] with inherent LD-targeting performance. The PA CDs were able to indicate the dynamic behavior of LDs and visualize the changes of bisphenol A-induced nonalcoholic fatty liver disease-like changes in a cellular model. The QSAR strategy of CDs demonstrated here is expected to be increasingly exploited as a powerful design tool for developing various organelle-targeting CDs.

4.
Chemosphere ; 287(Pt 1): 132030, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34461338

RESUMO

A biocomposite (PN-Fe3O4-PEI) was synthesized via the chemical modification of peanut husk (a low-cost adsorbent) with Fe3O4 particles and polyethyleneimine under benign environmental conditions. The modification agents used in this study were observed to overcome the challenges associated with the use pristine peanut husk with a concomitant enhancement in its efficiency as an adsorbent. Results from the characterization studies employed in this study confirmed PN-Fe3O4-PEI to be a crystalline magnetic adsorbent with a mesoporous structure. The adsorption property of the developed material (PN-Fe3O4-PEI) for wastewater treatment was investigated using Chromium (VI), Phosphates (PO43-) and Congo red (CR) as model pollutants. Using the batch method, PN-Fe3O4-PEI exhibited a maximum monolayer adsorption capacity of 58.4, 13.5 and 71.3 mg g-1 for Cr(VI), PO43- (as P g L-1) and CR, respectively and was dependent on temperature and initial adsorbate concentration. Kinetic studies revealed that the Elovich equation, the pseudo-second order kinetic model and double constant equation well described the uptake of Cr(VI), PO43- and CR onto PN-Fe3O4-PEI, respectively. These results may confirm the uptake of these pollutants to be mainly driven by chemical forces. In addition, PN-Fe3O4-PEI was observed to be efficient for the decontamination of the studied pollutants in real water samples as well as exhibit antibacterial properties towards the growth of S. aureus. These properties of PN-Fe3O4-PEI with its other excellent features such as high stability in solution, good regeneration properties and its facile retrieval from the solution using a magnet promote its suitability for practical wastewater treatment.

5.
Anal Chem ; 93(36): 12456-12463, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34449199

RESUMO

Molecular probe that enables in vivo imaging is the cornerstone of accurate disease diagnosis, prognostic estimation, and therapies. Although several nucleic acid-based probes have been reported for tumor detection, it is still a challenge to develop programmable methodology for accurately identifying tumors in vivo. Herein, a reconfigurable DNA hybridization-based reaction was constructed to assemble DNAzyme computing that contains an intracellular miRNA-unlocked entropy-driven catalysis module and an endogenous metal ion-responsive DNAzyme module for specific in vivo imaging. By reasonable design, the programmable DNAzyme computing can not only successfully distinguish tumor cells from normal cells but also enable tumor imaging in living mice. Due to its excellent operation with high specificity and sensitivity, this design may be broadly applied in the biological study and personalized medicine.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , MicroRNAs , Animais , DNA Catalítico/metabolismo , Camundongos , Hibridização de Ácido Nucleico
6.
J Org Chem ; 86(13): 9055-9066, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34157844

RESUMO

A visible-light-induced decarboxylation reaction was developed for the synthesis of alkylated benzimidazo[2,1-a]isoquinoline-6(5H)-ones and indolo[2,1-a]isoquinolin-6(5H)-ones under metal-free conditions. Impressively, metal catalysts and traditionally volatile organic solvents could be effectively avoided.


Assuntos
Isoquinolinas , Fotossíntese , Catálise
7.
Adv Healthc Mater ; 10(14): e2002268, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34165910

RESUMO

Wound healing is an essential and complex biological process. Research into its mechanism and factors that influence its effectiveness has led to better treatments. Changes in the microenvironment are demonstrated to affect wound healing. Cell polarity is a significant microenvironment-related parameter that is associated with many physiological and pathological activities. However, dynamic changes in polarity during wound healing have not been investigated. Monitoring cell polarity during wound healing may open up a new avenue for developing better treatments. Here, a method is developed to monitor cell polarity that involved taking advantage of the fascinating optical properties and biocompatibility of carbon dots (CDs). Specifically, near-infrared (NIR) polarity-sensitive N-phenyl-p-phenylenediamine (PPh-CDs) are successfully prepared, which exhibit high sensitivity to polarity, with 509-fold stronger fluorescence in dioxane than in water. The PPh-CDs are successfully applied to monitor the changes of lysosomal polarity during starvation conditions. Using this method, dynamic changes of polarity during wound healing of zebrafish are monitored for the first time. Upon an amputation performed at the zebrafish tail, stronger PPh-CDs fluorescence appeared at the wound sites, and the intensity increased for 25 min and then gradually decreased. This report provides an important experimental basis for investigating wound healing by employing polarity-sensitive CDs.


Assuntos
Carbono , Pontos Quânticos , Animais , Corantes Fluorescentes , Espectrometria de Fluorescência , Cicatrização , Peixe-Zebra
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120020, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34119770

RESUMO

DNA (cytosine-5)-methyltransferase1 (DNMT1) is the most abundant DNA methyltransferase in somatic cells, and it plays an important role in the initiation, occurrence, and rehabilitation of tumors. Herein, we developed a novel strategy for the detection of the level of DNMT1 in human plasma using the self-assembled nucleic acid probe signal amplification technology. In this method, the DNMT1 monoclonal antibody (McAbDNMT1) was immobilized on carboxyl magnetic beads to form immunomagnetic beads and then captured DNMT1 specifically. After that, DNMT1 polyclonal antibody (PcAbDNMT1) and biotinylated sheep anti-rabbit IgG (sheep anti rabbit IgG-Biotin) were sequentially added into the system to react with DNMT1 and form biotinylated double antibody sandwich immunomagnetic beads. In the presence of the bridging medium streptavidin, the biotinylated double antibody sandwich immunomagnetic beads would form a complex with biotinylated poly-fluorescein (Biotin-poly FAM), and the fluorescence intensity of the complex was proportional to the concentration of DNMT1. Immunomagnetic beads can capture the target DNMT1 in the sample, and Biotin-poly FAM can realize signal amplification. Using these strategies, we got a linear range of the system for DNMT1 level detection was from 2 nmol/L to 200 nmol/L, and the limit of detection (LOD) was 0.05 nmol/L. The method was successfully applied for the determination of DNMT1 in human plasma with the recovery of 101.3-106.0%. Therefore, this method has the potential for the detection of DNMT1 level in clinical diagnosis.


Assuntos
Biotina , DNA , Animais , Fluoresceína , Limite de Detecção , Coelhos , Ovinos , Estreptavidina
9.
Small ; 17(29): e2007174, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34047052

RESUMO

Exosomes, a class of small extracellular vesicles (30-150 nm), are secreted by almost all types of cells into virtually all body fluids. These small vesicles are attracting increasing research attention owing to their potential for disease diagnosis and therapy. However, their inherent heterogeneity and the complexity of bio-fluids pose significant challenges for their isolation. Even the "gold standard," differential centrifugation, suffers from poor yields and is time-consuming. In this context, recent developments in microfluidic technologies have provided an ideal system for exosome extraction and these devices exhibit some fascinating properties such as high speeds, good portability, and low sample volumes. In this review, the focus is on the state-of-the-art microfluidic technologies for exosome isolation and highlight potential directions for future research and development by analyzing the challenges faced by the current strategies.


Assuntos
Exossomos , Vesículas Extracelulares , Transporte Biológico , Exossomos/metabolismo , Humanos , Microfluídica
10.
Sci Total Environ ; 780: 146629, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34030339

RESUMO

This review is an attempt to assess the adsorption performance of different green adsorbents derived from agricultural waste materials (AWMs) that were used for the elimination of bisphenol A (BPA) from aqueous matrices. Different processes including grafting, polymerization, activation and chemical treatment have been applied to functionalize and modify agricultural waste materials for the purposes of increasing their adsorptive performances toward BPA. The highest reported adsorption capacity of adsorbent from agricultural waste for the uptake of BPA is the highly microporous carbon adsorbent derived from Argan nut shell (1408 mg g-1). Hydrogen bonding, hydrophobic and π-π interactions were reported in most studies as the main mechanisms governing the adsorption of BPA onto agricultural waste adsorbents. Equilibrium isotherm and kinetic studies for the uptake of BPA onto agricultural waste adsorbents were best described by Langmuir/Freundlich model and pseudo-second order model, respectively. Despite the effective elimination of BPA by various agricultural waste adsorbents, an appropriate selection of elution solvent is important for effective desorption of BPA from spent adsorbent. To date, ethanol, diethyl ether-methanol, methanol-acetic acid, mineral acids and sodium hydroxide are the most eluents applied for desorption of BPA molecules loaded onto AW-adsorbents. Looking toward the future, studies on the agricultural waste adsorbents based on polymers, activated carbons, nanoparticles and highly microporous carbons should be mostly considered by the researchers toward removing BPA. These future studies should be performed both in laboratory, pilot and industrial scales, and also should report the sustainable techniques for disposal of the spent AW-adsorbents after lose their adsorption performance on BPA.

11.
Biosens Bioelectron ; 188: 113337, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34030091

RESUMO

A dual-model "on-super off" photoelectrochemical (PEC)/ratiometric electrochemical (EC) biosensor based on signal enhancing and quenching combining three-dimensional (3D) DNA walker strategy was designed for the ultrasensitive and accurate detection of microRNA-224 (miRNA-224). The "signal on" PEC state was achieved by methylene blue labeled hairpin DNA (MB-DNA) for sensitizing CdS QDs. Then numerous transformational ferrocene labeled DNAs (Fc-DNAs) converted by target-induced 3D DNA walker amplification with the help of Ag nanocubes (NCs) label DNA (Ag-DNA) were introduced to open hairpin MB-DNA. Such configuration change would relocate the sensitizer MB and the quencher Fc, whereas energy transfer placed between Ag NCs and CdS QDs, thereby significantly quenching the PEC signal to obtain "super off" state. Meanwhile, these changes resulted in a decreased oxidation peak current of MB (IMB) and an increased that of Fc (IFc). MiRNA-224 was also detected on basis of the dual-signaling EC ratiometric method for complementary PEC detection. Benefiting from different mechanisms and relatively independent signal transduction, this approach not only avoided interference from difficult assembly but also outstandingly increased sensitivity by distance-controllable signal enhancing and quenching strategies. As a result, the detection ranges of 0.1-1000 fM with a low detection limit of 0.019 fM for PEC, and 0.52 to 500 fM with a low detection limit of 0.061 fM for EC, were obtained for miRNA-224, which opens a new avenue for designing numerous elegant biosensors with potential utility in bioanalysis and early disease diagnosis.


Assuntos
Técnicas Biossensoriais , MicroRNAs , DNA , Técnicas Eletroquímicas , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico
12.
Eur J Cancer Prev ; 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33859129

RESUMO

OBJECTIVES: The early detection, early diagnosis, and early treatment of lung cancer are the best strategies to improve the 5-year survival rate. Logistic regression analysis can be a helpful tool in the early detection of high-risk groups of lung cancer. Convolutional neural network (CNN) could distinguish benign from malignant pulmonary nodules, which is critical for early precise diagnosis and treatment. Here, we developed a risk assessment model of lung cancer and a high-precision classification diagnostic model using these technologies so as to provide a basis for early screening of lung cancer and for intelligent differential diagnosis. METHODS: A total of 355 lung cancer patients, 444 patients with benign lung disease and 472 healthy people from The First Affiliated Hospital of Zhengzhou University were included in this study. Moreover, the dataset of 607 lung computed tomography images was collected from the above patients. The logistic regression method was employed to screen the high-risk groups of lung cancer, and the CNN model was designed to classify pulmonary nodules into benign or malignant nodules. RESULTS: The area under the curve of the lung cancer risk assessment model in the training set and the testing set were 0.823 and 0.710, respectively. After finely optimizing the settings of the CNN, the area under the curve could reach 0.984. CONCLUSIONS: This performance demonstrated that the lung cancer risk assessment model could be used to screen for high-risk individuals with lung cancer and the CNN framework was suitable for the differential diagnosis of pulmonary nodules.

13.
J Colloid Interface Sci ; 598: 69-82, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33892443

RESUMO

Accessibility to quality and clean water has in recent times been compromised due to the presence of pollutants, thus posing as a threat to the survival of living organisms. The adsorption technique in this regard has been observed to be useful in the remediation process with the material used as the adsorbent playing an integral role. In this study, a novel biocomposite (PN-Fe3O4-IDA-Al) based on peanut husk (a low-cost material) was developed by functionalization with aluminum (Al), iminodiacetic acid (IDA) and Fe3O4. The efficiency of PN-Fe3O4-IDA-Al as an adsorbent for the remediation of wastewater was evaluated using Congo red (CR) and phosphates (PO43-) as model pollutants. The results from the characterization studies confirmed PN-Fe3O4-IDA-Al to have superparamagnetic properties which ensures its easy retrieval. Adsorption studies indicated that PN-Fe3O4-IDA-Al had a maximum monolayer capacity of 79.0 ± 2.0 and 16.8 ± 2.5 mg g-1 for CR and PO43- (according to P), respectively, which was significantly dependent on factors such as reaction time, solution pH, temperature and the presence of some common anions. The Freundlich model was observed to better describe both adsorption processes with chemisorption being the principal underlying mechanism. Results from using real water samples confirmed PN-Fe3O4-IDA-Al to be highly efficient for practical remediation processes. These results coupled with the synthesis of PN-Fe3O4-IDA-Al under benign conditions using low-cost materials help to expound the knowledge on the use of low cost materials as the basis for the development of highly efficient adsorbents for wastewater remediation.


Assuntos
Vermelho Congo , Poluentes Químicos da Água , Adsorção , Arachis , Concentração de Íons de Hidrogênio , Cinética , Fenômenos Magnéticos , Fosfatos , Poluentes Químicos da Água/análise
14.
Luminescence ; 36(7): 1584-1591, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33900056

RESUMO

In this work, novel types of nitrogen-doped carbon dots (N-CDs) were prepared from citric acid and glycine (GLY) as precursors through a simple pyrolysis method. The GLY-CDs showed strong fluorescence with a fluorescence quantum yield as high as 33.34% and good water solubility. The fluorescence of GLY-CDs could be selectively quenched by iron(III) ion (Fe3+ ) resulting in the non-fluorescent complex. Due to the high affinity of Fe3+ to adenosine-5'-triphosphate (ATP), the fluorescence of the GLY-CDs in GLY-CDs-Fe3+ could be recovered by ATP. Thereby, quantitatively fluorescent turn-on detection of ATP could be achieved. The fluorescence recovery ratio was linearly proportional to the concentration of ATP with a detection limit as low as 15.0 nM, indicating the CDs have high sensitivity. The GLY-CDs were successfully employed in the detection of ATP in serum and cell lysates.


Assuntos
Carbono , Pontos Quânticos , Trifosfato de Adenosina , Compostos Férricos , Corantes Fluorescentes , Nitrogênio , Espectrometria de Fluorescência
15.
Luminescence ; 36(7): 1592-1599, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33900668

RESUMO

A novel nitrogen-doped graphene quantum dots (N-GQDs) with a green fluorescence emission was synthesized through microwave method using citric acid and semicarbazide hydrochloride as reactants. The as-synthesized N-GQDs exhibited good stability, excellent water solubility, and negligible cytotoxicity. Due to intermolecular charge transfer, ferric ion (Fe3+ ) has a strong quenching effect on the N-GQDs. Fluorescence quenching has a linear relationship with the Fe3+ concentration in the range 0.02-12 µM. The detection limit was 1.43 nM. What is more, it is worth mentioning that the obtained N-GQDs showed high selectivity and sensitivity towards Fe3+ . Under the optimum conditions, the addition of 10-fold copper ions and 100-fold other metal ions had no influence on the detection of Fe3+ (0.8 µM), which indicated a higher sensitivity compared with that of the reported methods. Due to their excellent properties, the obtained N-GQDs was successfully applied for sensing and imaging Fe3+ in water samples and HeLa cells.


Assuntos
Grafite , Pontos Quânticos , Células HeLa , Humanos , Nitrogênio , Espectrometria de Fluorescência
16.
Bioorg Med Chem Lett ; 40: 127913, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33705905

RESUMO

Resveratrol is a natural polyhydroxy trans-stilbene product with many biological activities. One of the most striking biological activities of it is its anti-aging potential. Resveratrol can exhibit anti-aging activity via a variety of signaling pathways, however, the repair effect of it on kidney and brain injury in aging mice induced by d-galactose and its regulation on klotho gene expression have not been reported. Herein, the anti-aging activity of resveratrol and its effect on the repair of kidney and brain injuries in d-galactose-induced aging mice, as well as its regulation of klotho gene expression in these two tissues were investigated. The results indicated that resveratrol could significantly increase the aged cell viability and improve the pathological status of aging mice via inhibiting the formation of malondialdehyde and enhancing the activities of superoxide dismutase and catalase. The histological analysis suggested that resveratrol could remarkably repair the damages of kidney and brain tissues in aging mice. Moreover, PCR and western blot have shown that resveratrol could obviously increase the anti-aging klotho gene expression in the above tissues. The data in this paper further revealed and enriched the anti-aging mechanism of resveratrol, and the methods established in this study can be used as a tool to evaluate the anti-aging activity of drugs to a certain extent.


Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/química , Lesões Encefálicas/tratamento farmacológico , Insuficiência Renal/tratamento farmacológico , Resveratrol/química , Animais , Antioxidantes/farmacologia , Encéfalo , Catalase/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Galactose/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucuronidase/genética , Glucuronidase/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Rim , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Resveratrol/farmacologia , Transdução de Sinais , Superóxido Dismutase/metabolismo
17.
Environ Sci Pollut Res Int ; 28(28): 37322-37337, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33715124

RESUMO

A novel adsorbent (PN-Fe3O4-IDA-Zr) was developed from the chemical modification of peanut husk (a low cost material) with Fe3O4, iminodiacetic acid (IDA) and zirconium (Zr) and its efficacy for the sequestration of wastewater assessed using Alizarin red (AR) and Acid chrome blue K (AK) as model pollutants. To elucidate the characteristics of the formed adsorbent, analytical techniques such as the Bruauner-Emmet-Teller (BET) method, X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffractive spectroscopy (XRD) and vibrating sample magnetometer (VSM) were applied. Results from these studies confirmed the formation of a crystalline mesoporous adsorbent with surface properties which enhanced its usefulness. From the adsorption studies, it was observed that factors such as pH, salts, temperature and contact time influenced the uptake of the anionic dyes. The maximum monolayer capacity of PN-Fe3O4-IDA-Zr for AR was 49.4 mg g-1 (at 313 K) and was well fitted by the Langmuir model with the chemisorption process being the dominant reaction mechanism. In binary systems, PN-Fe3O4-IDA-Zr exhibited higher affinity for AR as compared with AK. The significant removal efficiency exhibited by this novel adsorbent as well as other unique features such as easy retrieval and high regeneration promotes its prospects as an adsorbent for practical wastewater remediation processes.


Assuntos
Corantes , Poluentes Químicos da Água , Adsorção , Arachis , Concentração de Íons de Hidrogênio , Iminoácidos , Cinética , Fenômenos Magnéticos , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise , Zircônio
18.
Org Lett ; 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33780256

RESUMO

A general and metal-free visible-light-induced decarboxylative arylation procedure at room temperature was described for the construction of acylated heterocyclic derivatives, such as benzimidazo/indolo[2,1-a]isoquinolin-6(5H)-ones, aroylazaspiro[4.5]trienones, thioflavones, and so on. This practical arylation procedure was conducted by using 2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN) as a photocatalyst under mild conditions, which avoided the use of an additional base, traditional heating, and metal reagents.

19.
J Food Sci ; 86(3): 1089-1096, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33751602

RESUMO

Weaning is the gradual process of introducing solids or semisolid foods into an infant's diet, in order to ensure their healthy growth. This study developed two kinds of formula weaning food based on roasted or extruded quinoa and millet flour, and evaluated their quality. A fructo-oligosaccharide (FOS)/galacto-oligosaccharide (GOS) mix was added to provide the prebiotic potential. The protein contents of the roasted quinoa-millet complementary food (RQMCF) and extruded quinoa-millet complementary food (EQMCF) were 16.7% and 17.74% higher, respectively, than that of commercial millet complementary food (CMCF). Both RQMCF and EQMCF provided sufficient levels of energy and minerals. Extrusion provided the foods with a lower viscosity, and higher solubility and water absorption ability than roasting. In vitro digestion results showed that EQMCF exhibited the highest starch and protein digestibility (89.76% and 88.72%, respectively) followed by RQMCF (87.75% and 86.63%) and CMCF (83.35% and 81.54%). The digestas of RQMCF and EQMCF after in vitro digestion exhibited prebiotic effects by promoting the growth of the probiotics (Lactobacillus plantarum and Lactobacillus delbrueckii). These results will contribute to developing complementary weaning foods for infants. PRACTICAL APPLICATION: This study has shown that extrusion is an efficient and stable processing method for producing infant complementary foods with low density, balanced nutrition, and high levels of starch and protein digestibility. Extruded quinoa-millet prebiotic complementary food can also promote the proliferation of probiotics. This will provide a new direction for developing novel infant formula weaning foods.


Assuntos
Chenopodium quinoa/química , Farinha/análise , Alimentos Formulados/análise , Fórmulas Infantis/química , Milhetes/química , Prebióticos/análise , Manipulação de Alimentos , Humanos , Lactente , Fórmulas Infantis/análise , Estado Nutricional , Desmame
20.
Anal Chim Acta ; 1153: 338283, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33714448

RESUMO

An ultrasensitive and selective photoelectrochemical (PEC) biosensor with cathodic background signal was developed for the detection of carcinoembryonic antigen (CEA) based on innovative plasmonic TiO2@Au nanoparticles//CdS quantum dots (TiO2@Au NPs//CdS QDs) photocurrent-direction switching system, coupling with hybridization chain reaction (HCR) for the signal amplification. Firstly, innovative TiO2@Au NPs were successfully fabricated through in situ ascorbic acid-reduction of Au NPs dispersed on TiO2 surface, and TiO2@Au NPs as the photoactive material showed a cathodic background signal. When target CEA existed, a sandwich-type reaction was performed in capture CEA aptamer-modified TiO2@Au NPs and trigger CEA aptamer. Interestingly, after HCR triggered by target CEA, a mass of CdS QDs were introduced into the biosensing platform, resulting in the formation of TiO2@Au NPs//CdS QDs system, along with the switch of photocurrents from cathodic to anodic. The obtained remarkable anodic photocurrent was depended on the localized surface plasmon resonance (LSPR) effect of Au between TiO2 and CdS. Under the optimal conditions, plasmonic TiO2@Au NPs//CdS QDs photocurrent-direction switching PEC biosensing platform with cathodic background signal exhibited ultrasensitive for the determination of CEA with a low limit of detection of 18.9 fg/mL. Importantly, the proposed PEC biosensor can eliminate the interferences of the initial photocurrent and background signal, and has high-efficiency anti-interference ability, satisfactory stability and excellent reproducibility, which may have great potentials in bioanalysis and disease diagnosis.


Assuntos
Técnicas Biossensoriais , Compostos de Cádmio , Nanopartículas Metálicas , Pontos Quânticos , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Reprodutibilidade dos Testes , Sulfetos , Titânio
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