Excellent Recovery Rate Research Articles

Development of novel FRET aptasensor based on the quenching ability of iron oxide-gold nanostars for the detection of aflatoxin M1

Detecting Aflatoxin M1 (AFM1) in food products is crucial due to its high toxicity and health risks. This study introduced a fluorescence donor material using Rhodamine-B-Isothiocyanate (RBITC)-doped silica nanoparticles (RDSN) combined with iron oxide‑gold nanostars (IOGNS) as a quencher. The composite aptasensor (RDSN/IOGNS) served as a Förster Resonance Energy Transfer (FRET) nanoprobe for sensitive and selective AFM1 detection. The fluorescence of aptamer-conjugated RDSN (apt-RDSN) was effectively quenched by complementary DNA-conjugated IOGNS (cDNA-IOGNS). Upon AFM1 introduction, apt-RDSN dissociated from the IOGNS surface, restoring the fluorescence signal. The fluorescence intensity correlated linearly with AFM1 concentration, achieving a detection limit of 0.15 ng/mL. Compared to conventional enzyme-linked immunosorbent assay (ELISA), this FRET aptasensor showed excellent recovery rate and relative standard deviation (RSD) in milk samples, highlighting its potential for practical AFM1 detection applications.

A Photoelectrochemical Biosensor Mediated by CRISPR/Cas13a for Direct and Specific Detection of MiRNA-21.

Direct detection of miRNA is currently limited by the complex amplification and reverse transcription processes of existing methods, leading to low sensitivity and high operational demands. Herein, we developed a CRISPR/Cas13a-mediated photoelectrochemical (PEC) biosensing platform for direct and sensitive detection of miRNA-21. The direct and specific recognition of target miRNA-21 by crRNA-21 eliminates the need for pre-amplification and reverse transcription of miRNA-21, thereby preventing signal distortion and enhancing the sensitivity and precision of target detection. When crRNA-21 binds to miRNA-21, it activates the trans-cleavage activity of CRISPR/Cas13a, leading to the non-specific cleavage of biotin-modified DNA with uracil bases (biotin-rU-DNA). This cleavage prevents the biotin-rU-DNA from being immobilized on the electrode surface. As a result, streptavidin cannot attach to the electrode via specific biotin binding, reducing spatial resistance and causing a positively correlated increase in the photocurrent response. This Cas-PEC biosensor has good analytical capabilities, linear responses between 10 fM and 10 nM, a minimum detection limit of 9 fM, and an excellent recovery rate in the analysis of real human serum samples. This work presented an innovative solution for detecting other biomarkers in bioanalysis and clinical diagnostics.

Determination of tetramethylammonium hydroxide in air using ion chromatography or ultra-performance liquid chromatography - high-resolution mass spectrometry

Tetramethylammonium hydroxide (TMAH) is extensively utilized in the semiconductor and optoelectronic industries, serving as either a developer or an etchant. TMAH possesses acute toxicity and alkaline corrosiveness, having caused several fatal and injurious accidents in Taiwan. However, there is currently a lack of methods available for assessing TMAH exposure. This study developed a method involving sampling with quartz fiber filters followed by ultrasonic agitation in 10 mL mobile phase, filtering, and analysis using either ion chromatography (IC) or ultra-performance liquid chromatography - high-resolution mass spectrometry (UPLC-HRMS). Utilizing the characteristics of HRMS, the compound analyzed was identified as tetramethylammonium ion (TMA+) through mass spectrometry analysis. The method exhibits excellent trapping capacity and recovery rate. The linear range of TMA+ for IC is 0.3 to 100 μg/mL, with a correlation coefficient of R = 0.9998. The linear range of TMA+ for UPLC-HRMS is 0.002 to 1 μg/mL, with a correlation coefficient of R = 0.996. The recovery rates for IC and HRMS were 116.6% and 90.6%, with corresponding coefficient of variation (CV) of 2.25% and 3.53%, respectively. Samples can be stored at room temperature for 28 days. Verification of this method was conducted at the TMAH factory, and the air concentrations measured in the TMAH filling area were 3.29 and 4.75 μg/m3 from IC and UPLC-HRMS, respectively. This method will be applied in the on-site analysis of occupational hazards for operators in chemical plants, technology factories, and recycling plants, aiming to evaluate risk values to protect the safety and health of workers and prevent occupational diseases.

CTAC Self-Assembled Alkylated β-Cyclodextrin Loaded onto Functionalized MWCNTs Electrochemical Sensor for NP Detection.

Nonylphenol (NP) is an important fine chemical raw material and intermediate that is widely utilized in industry and may be distributed in aquatic ecosystems. Following its entry into the food and water cycles, it can subsequently enter the human body and potentially harm the human reproductive system. For the purpose of monitoring NP in water, it is thus essential to build a straightforward, affordable, and robust electrochemical sensor. Based on a two-step chemical modification proceeding and an electrostatic self-assembly effect, a double-modified β-cyclodextrin functionalized multiwalled carbon nanotube sensor (HE-β-CD-CTAC/F-MWCNTs) has been successfully constructed. It incorporates the excellent host-guest interaction ability of β-cyclodextrin and the high chemical activity of cetyltrimethylammonium chloride (CTAC), and the carbon nanotubes have an enormous particular surface area and strong electrical conductivity. The electrochemical oxidation reaction of NP with the sensor is controlled by a surface adsorption process of equal numbers of protons and electrons. In accordance with the optimized experimental parameters, the limit of detection (LOD) for the sensor is 0.13 μM, and it responds linearly to NP in the concentration range of 1-200 μM. Meanwhile, the sensor has excellent repeatability, stability, and immunity to interference. For the detection of NP in real water samples, the sensor also showed an excellent recovery rate (92.8%-98.5%) and relative standard deviation (1.16%-3.26%).

One-pot construction of gradient colloidal gel coating for stable and efficient emulsion separation

Gradient gel coatings possess superior interfacial bonding strength and surface wettability, providing new ideas for the structure design of separation materials. However, simply and effectively combining colloidal gels that have excellent separation potential with gradient structure design remains a great challenge. Herein, a polymerization-induced microphase separation strategy based on metal ions is developed for constructing colloidal gel coatings with gradient structure on the stainless steel mesh. The colloidal gel is formed by hydrogen-bond complexation and microphase separation of acrylamide and methacrylic acid during polymerization. The metal ions generated by the hydrogen evolution corrosion of stainless steel mesh can not only be used to construct a continuous gradient structure by influencing the microphase separation process but also enhance the mechanical properties and stability of the gel coating. The preparation strategies of traditional gradient materials are limited in the manufacturing and application processes due to their complicated preparation procedures and potential requirement for special equipment assistance. In contrast, this strategy can simply and efficiently prepare colloidal gel coatings with continuous gradient structure by one-pot method under strict monomer ratio. Its unique colloid network demonstrates better wettability and permeability than conventional polymer gel. The prepared gradient colloidal gel coating exhibits excellent separation efficiency (above 99.9 %) and water flux recovery rate (≈98.75 %) in separating surfactant-stabilized emulsion. Therefore, this work provides new insights into the design and preparation of gradient colloidal gels, promoting their development in the field of water treatment.

Preparation of dual recognition adsorbents based on molecularly imprinted polymers and aptamer for highly sensitive recognition and enrichment of ochratoxin A

In light of the significant risks that mycotoxins posed to public health and environmental safety, this research developed an adsorbent MIPs/Apt/AuNPs@ZIF-67 (MA-AZ) utilizing a dual-recognition approach combining molecularly imprinted polymers (MIPs) and aptamer (Apt). This innovative method enabled the effective and highly selective recognition and enrichment of ochratoxin A (OTA). ZIF-67 was utilized as a carrier with a substantial specific surface area, and gold nanoparticles (AuNPs) were loaded on its surface to fix the thiol-modified Apt on the surface of the carrier. Then, an initiator was used to initiate a polymerization reaction, and the generated MIPs coated Apt/AuNPs@ZIF-67, thereby synthesizing the MA-AZ with a “synergistic recognition” effect. The Apt significantly increased the number of recognition sites within the imprinted cavities, and MIPs played roles in identifying targets, fixing and protecting Apt. The combination of the both produced the effect of “1+1>2”. The study on the adsorption performance of MA-AZ found that the adsorption capacity of MA-AZ could reach 65.1 mg/g, and the imprinted factor was 5.48. In addition, MA-AZ exhibited excellent stability, specificity, reusability and recovery rate. Thus, this study offers valuable insights for the recognition and enrichment of hazardous substances, and helps to promote the rapid development of safety detection.

Evaluation of Bacterial Viability for Fecal Microbiota Transplantation: Impact of Thawing Temperature and Storage Time.

Fecal Microbiota Transplantation (FMT) represents a promising therapeutic tool under study for several purposes and is currently applied to the treatment of recurrent Clostridioides difficile infection. However, since the use of fresh stool was affected by several issues linked to donor screening, the development of a frozen stool bank is a reliable option to standardize FMT procedures. Nevertheless, different environmental factors impact microbial viability. Herein, we report the effect of different thawing temperatures and storage conditions on bacterial suspensions in the FMT procedure. In total, 20 stool samples were divided into aliquots and tested across a combination of different storing periods (15, 30; 90 days) and thawing procedures (4 °C overnight, room temperature for 1 h; 37 °C for 5 min). Focusing on storage time, our data showed a significant reduction in viability for aerobic and anaerobic bacteria after thawing for 15 days, while no further reductions were observed until after 90 days. Instead, among the different thawing procedures, no significant differences were observed for aerobic bacteria, while for anaerobes, thawing at 37 °C for 5 min was more effective in preserving the bacterial viability. In conclusion, the frozen fecal microbiota remained viable for at least three months, with an excellent recovery rate in all three thawing conditions.

An electrochemical aptasensor based on MOF-derived bimetallic carbon nanocomposites Au@Cu-C for ultrasensitive detection of homocysteine on portable potentiostat

Homocysteine (Hcy), a metabolic intermediate of methionine, is a biomarker for neurological, cardiovascular and cerebrovascular diseases. Timely measurement of Hcy acts as a significant role in disease prevention and diagnosis. Given the fast response of the electrochemical sensing method, herein, a sensitive electrochemical aptasensor was proposed for the detection of Hcy. The aptasensor was constructed by utilizing the MOF-derived bimetallic carbon nanocomposites (Au@Cu-C) plus multi-walled carbon nanotubes (MWCNTs) as electrode modification materials and methylene blue (MB) as the signal marker. The Au@Cu-C was synthesized through hydrothermal methods, calcination and simple galvanic replacement reactions. The prepared Au@Cu-C enhance the electrical signal due to the synergistic effect of bimetallic alloy, while the specific morphology facilitated the immobilization of the aptamer. MB, served as the signal marker, can reflect the current changes of the aptasensor caused by the conformational change of aptamer before and after binding Hcy. As a result, the constructed electrochemical aptasensor exhibited a high sensitivity of 0.415 μA μM−1, a low detection limit of 0.017 μM and an excellent recovery rate in the detection of human serum samples. Besides, the detection was performed on the portable potentiostat which demonstrated the potential application of the aptasensor in medical diagnosis and on-site analysis.

Effects of co-assembly of gliadin and carboxymethyl cellulose on the high internal phase pickering emulsions: Rheology properties, 3D printing performance and oil-soluble nutrient delivery

High internal phase Pickering emulsions (HIPPEs) stabilized with gliadin-based particles have received considerable attention because of the advantages of easy access, low cost and clean label. However, the relatively weak self-supporting and thixotropic recovery properties limit their application in food 3D printing. The present study investigated the effects of co-assembly of gliadin and carboxymethyl cellulose (CMC) on the gel network structure, viscoelasticity, thixotropic recovery, 3D printing properties and β-carotene delivery performance of HIPPEs stabilized with gliadin-based colloid particles. The results showed that the combination of gliadin and CMC significantly enhanced the density of gel network structure of HIPPEs and endowed the HIPPEs solid-like viscoelasticity, moderate shear thinning behavior and excellent thixotropic recovery rate as well as 3D printability. The HIPPEs realized an optimal performance at a gliadin/CMC mass ratio of 2:1, with a thixotropic recovery rate up to 93.23 ± 0.72 %, and the corresponding printed 3D model had a smooth surface, regular shape, and good printing accuracy. In addition, the potential application of HIPPEs in delivery of oil-soluble nutrients was investigated using β-carotene as a model. The result suggested that the stability and bioaccessibility of β-carotene was significantly improved from 25.71 ± 0.29 % to 59.70 ± 0.99 % and 12.30 ± 0.11 % to 37.04 ± 0.76 % respectively as the existence of CMC. This study provides references for the construction and design of food 3D printing materials.

“Off-on” signal-switchable electrochemiluminescence aptasensor based on Cu2O-ABEI-AgNPs mediated signal amplification for the detection of profenofos

An “off-on” signal-switchable electrochemiluminescence (ECL) aptasensor was designed for the detection of profenofos based on Cu2O-ABEI-AgNPs as ECL enhancers. Cubic Cu2O was prepared as a core, and AgNO3 was reduced to silver nanoparticles (AgNPs) by N-(4-Aminobutyl)-N-ethylisoluminol (ABEI) as a shell on the Cu2O surface. The Cu2O with a large surface area could enhance the fixation of AgNPs. Cu2O and AgNPs were utilized as catalysts to enhance the double amplification ECL signals. Additionally, a molecular probe consisting of gold nanoparticles (AuNPs), a T-type aptamer (consisting of thymines “T”, referred to as TApt), and aptamer (Apt) was prepared (referred to as AuNPs-Apt-TApt). The presence of mercury ion (Hg2+) could potentially quench the ECL signal and bind the thymine-Hg2+-thymine (T-Hg2+-T) structure. The structure formed a probe with Apt and AuNPs. The complementary short chain of aptamer (CApt) was designed and immobilized on AgNPs. In the absence of profenofos, the Apt and CApt were bound through complementary base pairing. The probe was immobilized on the electrode, resulting in quenching of the signal (switched into “off”). However, upon the presence of profenofos, the probe was detached from the electrode, and the signal was restored (switched into “on”). Finally, the aptasensor had a broad detection range (1 ×10-3 ng/mL∼1 ×102 ng/mL) with a lower limit of detection (LOD, 3 ×10-4 ng/mL) and an excellent recovery rate (94.34%∼113.80%) for the detection of profenofos in vegetables. The aptasensor had good stability, repeatability and specificity.

A new method for the production of particles with heat-sensitive nutrients by combining low-temperature closed-loop spray drying and natural plant carriers

This work aimed to reduce the loss of thermally unstable nutrients during the powder production process using closed-loop spray drying using an innovative carrier, coconut husk powder. β-carotene was selected as the subject of this study because it decomposes easily, but it is essential for the human body. The use of coconut husk powder as the carrier achieved an excellent powder recovery rate (RR) and β-carotene concentration compared with whey protein isolate, maltodextrin, cellulose, pectin, casein, and other commonly used carriers. The optimal outlet air temperature for spray drying was also found to be 50-55 °C. Coconut husk powder showed an excellent powder recovery rate (84%) and concentration (0.32 mg/g), which is high compared with the other carriers, because of its multi-layered spherical structure. The coconut powder also increased the stability of β-carotene. After being exposed to a temperature of 85 °C for 6 h, coconut husk powder was more resistant to high temperatures than maltodextrin.

Probing robust electrochemical monitoring of dimetridazole using nanocrystalline hydroxyapatite-graphene oxide decorated Mn3O4 nanocomposite

Developing low-cost electrocatalysts with efficient, long-lasting electrode materials is of significant interest and presents a considerable challenge for electrochemical sensing applications in food contamination, particularly in the monitoring of dimetridazole (DMZ). In this study, we introduce a novel ternary nanocomposite, namely hydroxyapatite-intercalated graphene oxide-decorated manganese oxide (HAp/GO@Mn3O4), synthesized through straightforward hydrothermal and ultrasonication methods. The nanocomposite is subjected to thorough physicochemical and electrochemical characterization and utilized as an electrode material to enhance DMZ sensors. The ternary nanocomposite of HAp/GO@Mn3O4 delivers improved electrocatalytic activity because the synergistic features offer an enhanced electron transfer rate compared to the other GCE-modified electrodes. The developed sensitive chemical sensor probe exhibits optimized electrochemical conditions and significantly improves the electrode/electrolyte system. It demonstrates wide linear ranges (0.005–440.3 μM), a low limit of detection (LOD, 0.86×10−9 M), and excellent sensitivity (23.12 μA μM−1 cm−2). The sensor also displays reliable reproducibility, repeatability, selectivity, and cycle stability. Moreover, the developed sensor demonstrates its ability to accurately monitor DMZ food contamination samples with an excellent recovery rate in trace-level detection.

Poloxamer 407 Combined with Polyvinylpyrrolidone To Prepare a High-Performance Poly(ether sulfone) Ultrafiltration Membrane.

At present, the design and fabrication of polymer membranes with high permeability and good retention ability are still huge challenges. In this study, the commercial Poloxamer 407 (Pluronic F127) is selected as a multifunctional additive, and polyvinylpyrrolidone is used as a pore-forming agent to modify the poly(ether sulfone) membrane by liquid-liquid phase conversion technology to prepare an ultrafiltration membrane with excellent performance. The hydrophobic poly(propylene oxide) segment in Poloxamer 407 guarantees that this copolymer can be firmly anchored to the poly(ether sulfone) matrix, and the hydrophilic poly(ethylene oxide) segments in Poloxamer 407 impart a stronger hydrophilic nature to the modified membrane surface. Therefore, the permeability and hydrophilicity of the modified membrane are significantly improved and the modified membrane also has good stability. When the amount of Poloxamer 407 added to the casting solution reached 0.6 g, the water flux of the modified membrane was as high as 368 L m-2 h-1, and the rejection rate of bovine serum albumin was close to 98%. In the test to isolate organic small molecule dyes, the retention rate of the modified membrane to Congo red is 94.27%. In addition, the modified membrane shows an excellent water flux recovery rate and antifouling ability. It performs well in subsequent cycle tests and long-term membrane life tests and can be used repeatedly. Our work has resulted in poly(ether sulfone) membranes with good performance, which show great potential in the treatment of biomedical wastewater and the removal of industrial organic dye wastewater, it provides ideas for the development and application of amphiphilic polymer materials.

Synthesis of water-soluble CdS quantum dots for the fluorescence detection of tetracycline

An effective strategy for combating antibiotic-resistant bacteria (ARB) entails the early detection of antibiotics during the initial stages of water treatment facilities. In this context, cadmium sulfide quantum dots (CdS QDs) were employed for the precise detection of tetracycline (TET), an emerging contaminant, in water. CdS QDs with fluorescence properties were synthesized by culturing Citrobacter freundii bacteria. The CdS QDs were characterized by spectroscopy techniques, and the quantum efficiency was estimated to be 55.8% which is ∼2-fold high compared to the standard rhodamine-B solution. The fluorescence of CdS QDs was quenched at 440 nm in the presence of TET. The linear range of TET was varied from 10 to 100 μM with a lower limit of detection of ∼23 nM. The CdS QDs were used to detect TET in river water, tap water, and milk which showed an excellent recovery rate. Therefore, the novel biosynthesis CdS QDs can be a significant fluorescence probe for the detection of TET that shows exceptional sensitivity and selectivity.

An Enzymatic Biosensor Based on MgO Nanoparticles Grafted on Reduced Graphene Oxide Nanoflakes for the Ultrasensitive Detection of Phenolic Compounds from Wastewater

AbstractIn the present work, an enzymatic biosensor has been fabricated using reduced graphene‐magnesium oxide nanoflakes (rGO‐MgONf). For the fabrication of the bioelectrode, the synthesized rGO‐MgONf were electrophoretically deposited onto indium tin oxide (ITO) coated glass substrate, followed by the covalent immobilization of the Laccase (lac) enzyme. Electrochemical studies show an enhanced diffusion coefficient (10.29×10−12 cm2 s−1), and exchange current per geometric unit area (3.66 μA cm−2) on using the rGO‐MgONf/ITO electrode compared to the GO/ITO and MgO/ITO electrode. Further, the fabricated biosensor (lac/rGO‐MgONf/ITO) displayed excellent performance towards hydroquinone (Hq) detection, with a low limit of detection (0.15 μM), wide linear range (1.0–100.0 μM), and high sensitivity (10.0 μA μM−1 cm−2). The selectivity study suggests that the fabricated biosensor efficiently detects Hq in wastewater. Additionally, the fabricated biosensor shows good stability and reproducibility for detecting Hq in tap and river water with an excellent recovery rate.

Whole-genome detection using multivalent DNA-coated colloids

To minimize the incorrect use of antibiotics, there is a great need for rapid and inexpensive tests to identify the pathogens that cause an infection. The gold standard of pathogen identification is based on the recognition of DNA sequences that are unique for a given pathogen. Here, we propose and test a strategy to develop simple, fast, and highly sensitive biosensors that make use of multivalency. Our approach uses DNA-functionalized polystyrene colloids that distinguish pathogens on the basis of the frequency of selected short DNA sequences in their genome. Importantly, our method uses entire genomes and does not require nucleic acid amplification. Polystyrene colloids grafted with specially designed surface DNA probes can bind cooperatively to frequently repeated sequences along the entire genome of the target bacteria, resulting in the formation of large and easily detectable colloidal aggregates. Our detection strategy allows "mix and read" detection of the target analyte; it is robust and highly sensitive over a wide concentration range covering, in the case of our test target genome Escherichia coli bl21-de3, 10 orders of magnitude from [Formula: see text] to [Formula: see text] copies/mL. The sensitivity compares well with state-of-the-art sensing techniques and has excellent specificity against nontarget bacteria. When applied to real samples, the proposed technique shows an excellent recovery rate. Our detection strategy opens the way to developing a robust platform for pathogen detection in the fields of food safety, disease control, and environmental monitoring.

Rapeseed oil as the extraction solvent motivates fucoxanthin-loaded high internal phase emulsion preparation for food 3D printing

Fucoxanthin (FX), a non-provitamin A carotenoid pigment, is a well-known natural antioxidant contained in brown algae. The present study deals with an ultrasonic-assisted FX extraction process from Undaria pinnatifida with rapeseed oil as the solvent. Then, high internal phase emulsions (HIPEs) with the FX-rich rapeseed oil as the oil phase was constructed using a simple one-step method for food 3D printing. The FX-loaded HIPEs were stabilized by the gelatin (GE)-based microgel, which were prepared by GE complex coacervation with sodium alginate and transglutaminase cross-linking, for the improved delivery and stability of FX. FX-loaded HIPEs stabilized by 2 wt (wt)% GE-based microgel showed a small and uniform particle size and a stable microstructure. The HIPEs stabilized by 2 wt% GE-based microgel had the best FX stability (residual FX 84.81 ± 0.82%) and bioaccessibility (38.26 ± 1.21%). The excellent viscoelasticity, recovery rate and thixotropy of the HIPEs stabilized by 2 wt% GE-based microgel further confirmed the best 3D printing performance. Therefore, rapeseed oil as the extraction solvent motivates FX-loaded HIPEs preparation, and GE-based microgel concentration is crucial for 3D printing.

A microfluidics chemiluminescence immunosensor based on orientation of antibody for HIV-1 p24 antigen detection

The HIV-1 capsid protein, p24 antigen, is a recognizable early diagnostic biomarker for human immune deficiency virus (HIV) infection. However, the existing methods address the limitations of high cost, cumbersome operations, long analysis time, and insufficient sensitivity and selectivity. Herein, an antibody oriented microfluidic chemiluminescence biosensor based on multiple signal amplification strategy was developed for rapid and ultrasensitive detection of HIV-1 p24 antigen. The microfluidic device contained an upstream snake-shape mixing channel and a downstream ship-shape microcavity with micropillar arrays for sufficient mixing of CL reagents, efficient capture of p24 antigen, double antibody sandwich reaction, hybridization chain reaction (HCR) amplification and CL detection. The multiple signal amplification was realized by antibody orientation, multiple HCRs on antibody and initiator chain modified gold nanoparticles (Ab2-AuNPs-I), and HRP and AuNPs synergistic catalyzed CL reaction. Using the platform, the detection of target p24 is converted to the detection of nucleic acid with a limit detection of 0.212 pg mL−1 and excellent specificity within 2 h of total analysis time, which is better or comparable to previously reported biosensors. Moreover, the biosensor exhibited an excellent recovery rate ranging from 92.7% to 102.3%. Therefore, the proposed method holds great potential in clinical diagnosis.

Ossification of yellow ligament-lesser known common cause of thoracic myelopathy in Indian subcontinent treated surgically

Background: To undertake a study which outlines the clinical and radiological features of ossification of yellow ligament (OYL) causing thoracic myelopathy (TM) in Indian subcontinent, to assess the outcomes of surgical resection of yellow ligament and compare different preoperative factors that contribute to be a risk factor in the overall post-surgical recovery rates (RR). Methods: A retrospective analysis of prospectively collected data from a cohort of 45 patients who visited our spine OPD from January 2012 to December 2019 who underwent surgical decompression for TM due to OYL was studied. The surgical outcomes and RR were calculated, compared and pre operative risk factors which could possibly be involved in giving poorer RR were analysed. Results: Our study included 45 patients who underwent surgical resection of OYL for TM. On comparison of post operative improvement in myelopathic symptoms, pre-operative mJOA score of 4.56 had increased significantly to 7.83 at 2 years follow up. While the majority (80%) of patients had an excellent and good recovery rate while 16% of patients had a fair recovery rate and 4% had no change at all in comparison to pre-operative mJOA scores. Preoperative risk factors for poor outcomes were also analysed. Conclusions: Early and timely before the onset or progression of any neurologic involvement. The pre operative risk factors which could give guarded prognosis and lower RR are, the presence of intramedullary signal changes (myelomalacia), >6-10 months of progressive pre operative symptoms and an mJOA<5.

Molecular Docking Insight into the Label-Free Fluorescence Aptasensor for Ochratoxin A Detection.

Ochratoxin A (OTA) is the most common mycotoxin and can be found in wheat, corn and other grain products. As OTA pollution in these grain products is gaining prominence as a global issue, the demand to develop OTA detection technology has attracted increasing attention. Recently, a variety of label-free fluorescence biosensors based on aptamer have been established. However, the binding mechanisms of some aptasensors are still unclear. Herein, a label-free fluorescent aptasensor employing Thioflavin T (ThT) as donor for OTA detection was constructed based on the G-quadruplex aptamer of the OTA aptamer itself. The key binding region of aptamer was revealed by using molecular docking technology. In the absence of the OTA target, ThT fluorescent dye binds with the OTA aptamer to form an aptamer/ThT complex, and results in the fluorescence intensity being obviously enhanced. In the presence of OTA, the OTA aptamer binds to OTA because of its high affinity and specificity to form an aptamer/OTA complex, and the ThT fluorescent dye is released from the OTA aptamer into the solution. Therefore, the fluorescence intensity is significantly decreased. Molecular docking results revealed that OTA is binding to the pocket-like structure and surrounded by the A29-T3 base pair and C4, T30, G6 and G7 of the aptamer. Meanwhile, this aptasensor shows good selectivity, sensitivity and an excellent recovery rate of the wheat flour spiked experiment.