Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 20 de 32
Filter
1.
Int J Mol Sci ; 24(11)2023 May 26.
Article in English | MEDLINE | ID: covidwho-20232955

ABSTRACT

The term "liver disease" refers to any hepatic condition that leads to tissue damage or altered hepatic function and can be induced by virus infections, autoimmunity, inherited genetic mutations, high consumption of alcohol or drugs, fat accumulation, and cancer. Some types of liver diseases are becoming more frequent worldwide. This can be related to increasing rates of obesity in developed countries, diet changes, higher alcohol intake, and even the coronavirus disease 2019 (COVID-19) pandemic was associated with increased liver disease-related deaths. Although the liver can regenerate, in cases of chronic damage or extensive fibrosis, the recovery of tissue mass is impossible, and a liver transplant is indicated. Because of reduced organ availability, it is necessary to search for alternative bioengineered solutions aiming for a cure or increased life expectancy while a transplant is not possible. Therefore, several groups were studying the possibility of stem cells transplantation as a therapeutic alternative since it is a promising strategy in regenerative medicine for treating various diseases. At the same time, nanotechnological advances can contribute to specifically targeting transplanted cells to injured sites using magnetic nanoparticles. In this review, we summarize multiple magnetic nanostructure-based strategies that are promising for treating liver diseases.


Subject(s)
COVID-19 , Liver Diseases , Nanostructures , Humans , Regenerative Medicine , Hepatocytes/transplantation , COVID-19/therapy , Liver Diseases/therapy , Stem Cells , Liver Regeneration , Magnetic Phenomena
2.
Biosens Bioelectron X ; 13: 100289, 2023 May.
Article in English | MEDLINE | ID: covidwho-2296697

ABSTRACT

The recent emergence of human coronaviruses (CoVs) causing severe acute respiratory syndrome (SARS) is posing a great threat to global public health. Therefore, the rapid and accurate identification of pathogenic viruses plays a vital role in selecting appropriate treatments, saving people's lives and preventing epidemics. Nucleic acids, including deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), are natural biopolymers composed of nucleotides that store, transmit, and express genetic information. Applications of nucleic acid detection range from genotyping and genetic prognostics, to expression profiling and detection of infectious disease. The nucleic acid detection for infectious diseases is widely used, as evidenced by the widespread use of COVID-19 tests for the containment of the pandemic. Nanotechnology influences all medical disciplines and has been considered as an essential tool for novel diagnostics, nanotherapeutics, vaccines, medical imaging, and the utilization of biomaterials for regenerative medicine. In this review, the recent advances in the development of nanotechnology-based diagnostic methods for coronavirus, and their applications in nucleic acid detection are discussed in detail. The techniques for the amplification of nucleic acids are summarized, as well as the use of magnetic nanoparticles for nucleic acid extraction. Besides, current challenges and future prospects are proposed, along with the great potential of nanotechnology for the effective diagnosis of coronavirus.

3.
Talanta ; 258: 124479, 2023 Jun 01.
Article in English | MEDLINE | ID: covidwho-2255880

ABSTRACT

The ongoing outbreak of the novel coronavirus disease 2019 (COVID-19) draws worldwide concerns due to its long incubation period and strong infectivity. Although RT-PCR-based methods are being widely applied for clinical diagnosis, timely and accurate diagnosis towards COVID-19 causing virus, the SARS-CoV-2, is still limited due to labor-intensive and time-consuming operations. Herein, we report a new viral RNA extraction method based on poly-(amino ester) with carboxyl group (PC)-coated magnetic nanoparticles (pcMNPs) for the sensitive detection of SARS-CoV-2. This method combines the lysis and binding steps into one step, and refines multiple washing steps into one step, giving a turnaround time of less than 9 min. Furthermore, the extracted pcMNP-RNA complexes can be directly introduced into subsequent RT-PCR reactions without elution. This simplified viral RNA method could be well adapted in fast manual and automated high-throughput nucleic acids extraction protocols suitable for different scenarios. A high sensitivity down to 100 copies/mL and a linear correlation between 100 and 106 copies/mL of SARS-CoV-2 pseudovirus particles are achieved in both protocols. Benefitting from the simplicity and excellent performances, this new method can dramatically improve the efficiency and reduce operational requirements for the early clinical diagnosis and large-scale SARS-CoV-2 nucleic acid screening.


Subject(s)
Magnetite Nanoparticles , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , COVID-19/diagnosis , RNA, Viral/analysis , RNA, Viral/genetics , Sensitivity and Specificity
4.
Biointerface Research in Applied Chemistry ; 13(3), 2023.
Article in English | Scopus | ID: covidwho-2243783

ABSTRACT

Amplification of the RNA from the Covid-19 virus is considered the main objective of the molecular diagnosis of SARS-Cov-2. However, the use of target-based amplification methods such as polymerase chain reaction requires a step to convert the RNA of the Covid-19 virus into a DNA template to lead to amplification. In addition, isolating the RNA of the Covid-19 virus requires RNA purification kits, which will increase the time and costs of molecular detection of this virus. In this study, the magnetic nanoprobe is introduced that it could capture and amplify Covid-19 RNA through an isothermal amplification process called loop-mediated isothermal amplification without requiring a step to convert the viral RNA into a DNA template. By using the engineered sequences corresponding to the target nucleic acid attached to magnetic nanoparticles, it becomes possible to identify the target RNA of this virus through color changes due to pH changes that can be seen with the naked eye due to the presence of pH indicators in the reaction mix. According to the isothermal amplification of the viral RNA via LAMP assisted with the magnetic nanoprobe, the nanomolecular method eliminated the need for special equipment and the time for detecting Covid-19 in specimens. © 2022 by the authors.

5.
Chinese Chemical Letters ; : 108092, 2022.
Article in English | ScienceDirect | ID: covidwho-2165128

ABSTRACT

Nucleic acid detection (NAD) based on real-time polymerase chain reaction (real-time PCR) is gold standard for infectious disease detection. Magnetic nanoparticles (MNPs) are widely used for nucleic acid extraction (NAE) because of their excellent properties. Microfluidic technology makes automated NAD possible. However, most of the NAD microfluidic chips are too complex to be applied to point-of-care (POC) testing. In this paper, a simple-structure cartridge was developed for POC detection of infectious diseases. This self-contained cartridge can be divided into a magnetic-controlled NAE part, a valve-piston combined fluidic control part and a PCR chip, which is able to extract nucleic acid from up to 500 μL of liquid samples by MNPs and finish the detection process from "sample in” to "answer out” automatically. Performance tests of the cartridges show that it met the demands of automated NAD. Results of on-cartridge detection of hepatitis B virus (HBV) demonstrated that this system has good uniformity and no cross-contamination between different cartridges, and the limit of detection (LOD) of this system for HBV in serum is 50 IU/mL. Multiplex detections of severe acute respiratory syndrome coronaviruses 2 (SARS-CoV-2) with a concentration of 500 copies/mL were carried out on the system and 100% positive detection rate was achieved.

6.
ACS Appl Bio Mater ; 5(11): 5140-5147, 2022 Nov 21.
Article in English | MEDLINE | ID: covidwho-2096625

ABSTRACT

Severe acute respiratory syndrome coronavirus 2's (SARS-CoV-2) rapid global spread has posed a significant threat to human health, and similar outbreaks could occur in the future. Developing effective virus inactivation technologies is critical to preventing and overcoming pandemics. The infection of SARS-CoV-2 depends on the binding of the spike glycoprotein (S) receptor binding domain (RBD) to the host cellular surface receptor angiotensin-converting enzyme 2 (ACE2). If this interaction is disrupted, SARS-CoV-2 infection could be inhibited. Magnetic nanoparticle (MNP) dispersions exposed to an alternating magnetic field (AMF) possess the unique ability for magnetically mediated energy delivery (MagMED); this localized energy delivery and associated mechanical, chemical, and thermal effects are a possible technique for inactivating viruses. This study investigates the MNPs' effect on vesicular stomatitis virus pseudoparticles containing the SARS-CoV-2 S protein when exposed to AMF or a water bath (WB) with varying target steady-state temperatures (45, 50, and 55 °C) for different exposure times (5, 15, and 30 min). In comparison to WB exposures at the same temperatures, AMF exposures resulted in significantly greater inactivation in multiple cases. This is likely due to AMF-induced localized heating and rotation of MNPs. In brief, our findings demonstrate a potential strategy for combating the SARS-CoV-2 pandemic or future ones.


Subject(s)
COVID-19 , Magnetite Nanoparticles , Humans , SARS-CoV-2 , Magnetite Nanoparticles/therapeutic use , Peptidyl-Dipeptidase A/chemistry , Magnetic Fields
7.
J Nanobiotechnology ; 20(1): 393, 2022 Aug 31.
Article in English | MEDLINE | ID: covidwho-2009412

ABSTRACT

High-quality point-of-care is critical for timely decision of disease diagnosis and healthcare management. In this regard, biosensors have revolutionized the field of rapid testing and screening, however, are confounded by several technical challenges including material cost, half-life, stability, site-specific targeting, analytes specificity, and detection sensitivity that affect the overall diagnostic potential and therapeutic profile. Despite their advances in point-of-care testing, very few classical biosensors have proven effective and commercially viable in situations of healthcare emergency including the recent COVID-19 pandemic. To overcome these challenges functionalized magnetic nanoparticles (MNPs) have emerged as key players in advancing the biomedical and healthcare sector with promising applications during the ongoing healthcare crises. This critical review focus on understanding recent developments in theranostic applications of functionalized magnetic nanoparticles (MNPs). Given the profound global economic and health burden, we discuss the therapeutic impact of functionalized MNPs in acute and chronic diseases like small RNA therapeutics, vascular diseases, neurological disorders, and cancer, as well as for COVID-19 testing. Lastly, we culminate with a futuristic perspective on the scope of this field and provide an insight into the emerging opportunities whose impact is anticipated to disrupt the healthcare industry.


Subject(s)
COVID-19 Drug Treatment , COVID-19 , Magnetite Nanoparticles , Nanoparticles , COVID-19/diagnosis , COVID-19 Testing , Chronic Disease , Humans , Magnetite Nanoparticles/therapeutic use , Nanomedicine , Pandemics
8.
Anal Chim Acta ; 1225: 340246, 2022 Sep 08.
Article in English | MEDLINE | ID: covidwho-1982438

ABSTRACT

Protein-based diagnostics are the standard of care for screening and diagnosing a broad range of diseases and medical conditions. The current gold standard method for quantifying proteins in clinical specimens is the enzyme-linked immunosorbent assay (ELISA), which offers high analytical sensitivity, can process many samples at once, and is widely available in many diagnostic laboratories worldwide. However, running an ELISA is cumbersome, requiring multiple liquid handling and washing steps, and time-intensive (∼2 - 4 h per test). Here, we demonstrate a unique magneto-ELISA that utilizes dually labeled magnetic nanoparticles (DMPs) coated with horseradish peroxidase (HRP) and an HRP-conjugated detection antibody, enabling rapid immunomagnetic enrichment and signal amplification. For proof of concept, this assay was used to detect Plasmodium falciparum histidine-rich protein 2 (PfHRP2), a malaria parasite biomarker, which exhibited a lower limit of detection of 2 pg mL-1 (33 fM) in human serum. Measurements of PfHRP2 in clinical blood samples from individuals with and without P. falciparum infection revealed that this magneto-ELISA offers a superior diagnostic accuracy compared to a commercial PfHRP2 ELISA kit. We also demonstrate the versatility of this platform by adapting it for the detection of SARS-CoV-2 nucleocapsid protein, which could be detected at concentrations as low as 8 pg mL-1 (174 fM) in human serum. In addition to its high analytical performance, this assay can be completed in 30 min, requires no specialized equipment, and is compatible with standard microplate readers and ELISA protocols, allowing it to integrate readily into current clinical practice.


Subject(s)
COVID-19 , Malaria, Falciparum , Nanoparticles , Enzyme-Linked Immunosorbent Assay/methods , Humans , Malaria, Falciparum/diagnosis , Malaria, Falciparum/parasitology , Plasmodium falciparum , SARS-CoV-2
9.
Biointerface Research in Applied Chemistry ; 13(3), 2023.
Article in English | Scopus | ID: covidwho-1965108

ABSTRACT

Amplification of the RNA from the Covid-19 virus is considered the main objective of the molecular diagnosis of SARS-Cov-2. However, the use of target-based amplification methods such as polymerase chain reaction requires a step to convert the RNA of the Covid-19 virus into a DNA template to lead to amplification. In addition, isolating the RNA of the Covid-19 virus requires RNA purification kits, which will increase the time and costs of molecular detection of this virus. In this study, the magnetic nanoprobe is introduced that it could capture and amplify Covid-19 RNA through an isothermal amplification process called loop-mediated isothermal amplification without requiring a step to convert the viral RNA into a DNA template. By using the engineered sequences corresponding to the target nucleic acid attached to magnetic nanoparticles, it becomes possible to identify the target RNA of this virus through color changes due to pH changes that can be seen with the naked eye due to the presence of pH indicators in the reaction mix. According to the isothermal amplification of the viral RNA via LAMP assisted with the magnetic nanoprobe, the nanomolecular method eliminated the need for special equipment and the time for detecting Covid-19 in specimens. © 2022 by the authors.

10.
Biochip J ; : 1-15, 2022 Jul 05.
Article in English | MEDLINE | ID: covidwho-1926100

ABSTRACT

During the ongoing COVID-19 pandemic, the development of point-of-care (POC) detection with high sensitivity and rapid detection time is urgently needed to prevent transmission of infectious diseases. Magnetic nanoparticles (MNPs) have been considered attractive materials for enhancing sensitivity and reducing the detection time of conventional immunoassays due to their unique properties including magnetic behavior, high surface area, excellent stability, and easy biocompatibility. In addition, detecting target analytes through color development is necessary for user-friendly POC detection. In this review, recent advances in different types of MNPs-based immunoassays such as improvement of the conventional enzyme-linked immunosorbent assay (ELISA), immunoassays based on the peroxidase-like activity of MNPs and based on the dually labeled MNPs, filtration method, and lateral-flow immunoassay are described and we analyze the advantages and strategies of each method. Furthermore, immunoassays incorporating MNPs for COVID-19 diagnosis through color development are also introduced, demonstrating that MNPs can become common tools for on-site diagnosis.

11.
Nanomaterials (Basel) ; 12(12)2022 Jun 14.
Article in English | MEDLINE | ID: covidwho-1911490

ABSTRACT

Lateral flow immunoassays for detecting biomarkers in body fluids are simple, quick, inexpensive point-of-care tests widely used in disease surveillance, such as during the coronavirus disease 2019 (COVID-19) pandemic. Improvements in sensitivity would increase their utility in healthcare, food safety, and environmental control. Recently, biofunctional magnetic nanoclusters have been used to selectively label target proteins, which allows their detection and quantification with a magneto-inductive sensor. This type of detector is easily integrated with the lateral flow immunoassay format. Pneumolysin is a cholesterol-dependent cytolysin and one of the most important protein virulence factors of pneumonia produced by Streptococcus pneumoniae. It is recognized as an important biomarker for diagnosis in urine samples. Pneumonia is the infectious disease that causes the most deaths globally, especially among children under five years and adults over 65 years, most of them in low- and middle-income countries. There especially, a rapid diagnostic urine test for pneumococcal pneumonia with high sensitivity and specificity would be helpful in primary care. In this work, a lateral flow immunoassay with magnetic nanoclusters conjugated to anti-pneumolysin antibodies was combined with two strategies to increase the technique's performance. First, magnetic concentration of the protein before the immunoassay was followed by quantification by means of a mobile telephone camera, and the inductive sensor resulted in detection limits as low as 0.57 ng (telephone camera) and 0.24 ng (inductive sensor) of pneumolysin per milliliter. Second, magnetic relocation of the particles within the test strip after the immunoassay was completed increased the detected signal by 20%. Such results obtained with portable devices are promising when compared to non-portable conventional pneumolysin detection techniques such as enzyme-linked immunosorbent assays. The combination and optimization of these approaches would have excellent application in point-of-care biodetection to reduce antibiotic misuse, hospitalizations, and deaths from community-acquired pneumonia.

12.
Nano Futures ; 6(2):23, 2022.
Article in English | Web of Science | ID: covidwho-1895744

ABSTRACT

Pandemics such as COVID-19 have highlighted the importance of point-of-care sensors for testing, tracing, and treatment to minimize and manage infection. Biosensors have been widely deployed in portable devices such as glucose sensors and pregnancy tests. Their development for point-of-exposure virus detection or point-of-care devices is anticipated but their reliability for the accurate detection of viruses is critical. Nanomaterials, such as metal nanoparticles (NPs), magnetic NPs, quantum dots, carbon-based nanomaterials, and molecularly imprinted polymer (MIP) NPs, have been utilized in biosensors to enhance sensitivity. Molecular imprinting is a cost-effective method to synthesize polymers for selective binding, which have excellent properties as biosensors. More research on MIP NPs can be expected in the near future. The utilization of nanomaterials in several types of transducers for biosensor devices is also illustrated to give an overview of their use. Finally, a summary is given together with a future perspective on how biosensors can be further developed as reliable, portable viral biosensors.

13.
Chemistryselect ; 7(21):24, 2022.
Article in English | Web of Science | ID: covidwho-1885452

ABSTRACT

Zoonotic infections belong to multiple infectious diseases transferred from animals to humans. Now, the treatment and diagnosis of zoonotic infections are perplexing due to genetic mutations, target site modifications, and multi-drug resistance. Despite their benefits, most diagnostic molecular techniques have certain limits in terms of repeatability and sensitivity, mainly due to the heterogeneity among the diverse family of zoonotic pathogens. Therefore, developing more efficient and cost-effective theranostics tools is the need of the hour to address these concerns. For this purpose, nanotechnology has revolutionized medicine with versatile potential capabilities for diagnosing and treating zoonosis via the targeted and controlled delivery of antimicrobial drugs via binding to the overexpressed infectious macrophages. Massive advancements have been made in fabricating novel nano-based formulations to control zoonosis based on the use of poly(ethylenimine)-conjugated nanomicelles, mannosylated thiolated chitosan (MTC)-coated PM-loaded PLGA NPs, mannose linked thiolated nanocarriers, adjuvanted pDNA hydrogel, arginine-based nanocarriers, quantum dots to treat and diagnose a wide range of zoonotic diseases, including zoonotic influenza, salmonellosis, leishmaniasis, rabies, brucellosis, Lyme Disease, tuberculosis, and other infections caused by West Nile Virus, emerging coronaviruses (SARS, MERS, COVID-19), in a preferentially targeted way. Recently developed anti-pathogen loaded-nanoformulations with enhanced cellular uptake, biocompatibility, and hemocompatibility have shown the ability to cross biological barriers when orally administrated. Therefore, this article reviewed the latest milestones and future growth areas in the field of efficient theranostics platforms to manage zoonotic infections.

14.
Adv Healthc Mater ; 11(17): e2200031, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-1881384

ABSTRACT

Developing efficient and highly sensitive diagnostic techniques for early detections of pathogenic viruses such as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is vitally important for preventing its widespread. However, the conventional polymerase chain reaction (PCR)-based detection features high complexity, excessive time-consumption, and labor-intensiveness, while viral protein-based detections suffer from moderate sensitivity and specificity. Here, a non-PCR but ultrasensitive viral RNA detection strategy is reported based on a facile nanoprobe-coupling strategy without enzymatic amplification, wherein PCR-induced bias and other shortcomings are successfully circumvented. This approach endows the viral RNA detection with ultra-low background to maximum signal ratio in the linear signal amplification by using Au nanoparticles as reporters. The present strategy exhibits 100% specificity toward SARS-CoV-2 N gene, and ultrasensitive detection of as low as 52 cp mL-1 of SARS-CoV-2 N gene without pre-PCR amplification. This approach presents a novel ultrasensitive tool for viral RNA detections for fighting against COVID-19 and other types of pathogenic virus-caused diseases.


Subject(s)
COVID-19 , Metal Nanoparticles , COVID-19/diagnosis , COVID-19 Testing , Gold , Humans , Nucleic Acid Amplification Techniques/methods , Polymerase Chain Reaction , RNA, Viral/genetics , SARS-CoV-2/genetics , Sensitivity and Specificity
15.
Talanta ; 243: 123356, 2022 Jun 01.
Article in English | MEDLINE | ID: covidwho-1778464

ABSTRACT

The increasing mutation frequency of the SARS-CoV-2 virus and the emergence of successive variants have made correct diagnosis hard to perform. Developing efficient and accurate methods to diagnose infected patients is crucial to effectively mitigate the pandemic. Here, we developed an electrochemical immunosensor based on SARS-CoV-2 antibody cocktail-conjugated magnetic nanoparticles for the sensitive and accurate detection of the SARS-CoV-2 virus and its variants in nasopharyngeal swabs. The application of the antibody cocktail was compared with commercially available anti-SARS-CoV-2 S1 (anti-S1) and anti-S2 monoclonal antibodies. After optimization and calibration, the limit of detection (LOD) determination demonstrated a LOD = 0.53-0.75 ng/mL for the antibody cocktail-based sensor compared with 0.93 ng/mL and 0.99 ng/mL for the platforms using anti-S1 and anti-S2, respectively. The platforms were tested with human nasopharyngeal swab samples pre-diagnosed with RT-PCR (10 negatives and 40 positive samples). The positive samples include the original, alpha, beta, and delta variants (n = 10, for each). The polyclonal antibody cocktail performed better than commercial anti-S1 and anti-S2 antibodies for all samples reaching 100% overall sensitivity, specificity, and accuracy. It also showed a wide range of variants detection compared to monoclonal antibody-based platforms. The present work proposes a versatile electrochemical biosensor for the indiscriminate detection of the different variants of SARS-CoV-2 using a polyclonal antibody cocktail. Such diagnostic tools allowing the detection of variants can be of great efficiency and economic value in the fight against the ever-changing SARS-CoV-2 virus.


Subject(s)
Biosensing Techniques , COVID-19 , Magnetite Nanoparticles , COVID-19/diagnosis , Humans , Immunoassay , SARS-CoV-2/genetics
16.
IET Nanobiotechnol ; 16(3): 85-91, 2022 May.
Article in English | MEDLINE | ID: covidwho-1758388

ABSTRACT

Mesoporous magnetic nanoparticles of haematite were synthesised using plant extracts according to bioethics principles. The structural, physical and chemical properties of mesoporous Fe2 O3 nanoparticles synthesised with the green chemistry approach were evaluated by XRD, SEM, EDAX, BET, VSM and HRTEM analysis. Then, their toxicity against normal HUVECs and MCF7 cancer cells was evaluated by MTT assay for 48 h. These biogenic mesoporous magnetic nanoparticles have over 71% of doxorubicin loading efficiency, resulting in a 50% reduction of cancer cells at a 0.5 µg.ml-1 concentration. Therefore, it is suggested that mesoporous magnetic nanoparticles be used as a multifunctional agent in medicine (therapeutic-diagnostic). The produced mesoporous magnetic nanoparticles with its inherent structural properties such as polygonal structure (increasing surface area to particle volume) and porosity with large pore volume became a suitable substrate for loading the anti-cancer drug doxorubicin.


Subject(s)
Nanoparticles , Silicon Dioxide , Doxorubicin/chemistry , Doxorubicin/pharmacology , Drug Carriers/chemistry , Drug Delivery Systems/methods , Drug Liberation , Humans , Nanoparticles/chemistry , Porosity , Silicon Dioxide/chemistry
17.
National Technical Information Service; 2020.
Non-conventional in English | National Technical Information Service | ID: grc-753648

ABSTRACT

Traumatic brain injury (TBI) currently afflicts 357,000 enlisted military men and women in the US Armed Services. For the most common form of TBI, Mild Traumatic Brain Injury (mTBI) most patients recover within a year following the incident, but 10-20 of mild cases result in a long-term disability including seizures and emotional and behavioral issues. Although much has been learned about molecular changes in the brain following injury, access to these biomarkers following mTBI is lacking. The accurate diagnosis and precise individual clinical management of traumatic brain injury (TBI) is limited by the lack of accessible molecular biomarkers that are informative regarding the unique mixture of injury mechanisms in each TBI patient.

18.
Applied Sciences ; 11(21):9786, 2021.
Article in English | ProQuest Central | ID: covidwho-1674438

ABSTRACT

Frequent tests for CD4+ T cell counting are important for the treatment of patients with immune deficiency;however, the routinely used fluorescence-activated cell-sorting (FACS) gold standard is costly and the equipment is only available in central hospitals. In this study, we developed an alternative simple approach (shortly named as the MACS-Countess system) for CD4+ T cell counting by coupling magnetic activated cell sorting (MACS) to separate CD4+ T cells from blood, followed by counting the separated cells using CountessTM, an automated cell-counting system. Using the cell counting protocol, 25 µL anti-CD4 conjugated magnetic nanoparticles (NP-CD4, BD Bioscience) were optimized for separating CD4+ T cells from 50 µL of blood in PBS using a DynamagTM-2 magnet, followed by the introduction of 10 µL separated cells into a CountessTM chamber slide for automated counting of CD4+ T cells. To evaluate the reliability of the developed method, 48 blood samples with CD4+ T cell concentrations ranging from 105 to 980 cells/µL were analyzed using both MACS-Countess and FACS. Compared with FACS, MACS-Countess had a mean bias of 3.5% with a limit of agreement (LoA) ranging from −36.4% to 43.3%, which is close to the reliability of the commercial product, PIMA analyzer (Alere), reported previously (mean bias 0.2%;LoA ranging from −42% to 42%, FACS as reference). Further, the MACS-Countess system requires very simple instruments, including only a magnet and an automated cell counter, which are affordable for almost every lab located in a limited resource region.

19.
Nanomaterials (Basel) ; 12(2)2022 Jan 08.
Article in English | MEDLINE | ID: covidwho-1637239

ABSTRACT

Today, public health is one of the most important challenges in society. Cancer is the leading cause of death, so early diagnosis and localized treatments that minimize side effects are a priority. Magnetic nanoparticles have shown great potential as magnetic resonance imaging contrast agents, detection tags for in vitro biosensing, and mediators of heating in magnetic hyperthermia. One of the critical characteristics of nanoparticles to adjust to the biomedical needs of each application is their polymeric coating. Fatty acid coatings are known to contribute to colloidal stability and good surface crystalline quality. While monolayer coatings make the particles hydrophobic, a fatty acid double-layer renders them hydrophilic, and therefore suitable for use in body fluids. In addition, they provide the particles with functional chemical groups that allow their bioconjugation. This work analyzes three types of self-assembled bilayer fatty acid coatings of superparamagnetic iron oxide nanoparticles: oleic, lauric, and myristic acids. We characterize the particles magnetically and structurally and study their potential for resonance imaging, magnetic hyperthermia, and labeling for biosensing in lateral flow immunoassays. We found that the myristic acid sample reported a large r2 relaxivity, superior to existing iron-based commercial agents. For magnetic hyperthermia, a significant specific absorption rate value was obtained for the oleic sample. Finally, the lauric acid sample showed promising results for nanolabeling.

20.
Talanta ; 241: 123243, 2022 May 01.
Article in English | MEDLINE | ID: covidwho-1633997

ABSTRACT

Viral diseases are the primary source of death, making a worldwide influence on healthcare, social, and economic development. Thus, diagnosis is the vital approach to the main aim of virus control and elimination. On the other hand, the prompt advancement of nanotechnology in the field of medicine possesses the probability of being beneficial to diagnose infections normally in labs as well as specifically. Nanoparticles are efficiently in use to make novel strategies because of permitting analysis at cellular in addition to the molecular scale. Henceforth, they assist towards pronounced progress concerning molecular analysis at the nanoscale. In recent times, magnetic nanoparticles conjugated through covalent bonds to bioanalytes for instance peptides, antibodies, nucleic acids, plus proteins are established like nanoprobes aimed at molecular recognition. These modified magnetic nanoparticles could offer a simple fast approach for extraction, purification, enrichment/concentration, besides viruses' recognition precisely also specifically. In consideration of the above, herein insight and outlook into the limitations of conventional methods and numerous roles played by magnetic nanoparticles to extract, purify, concentrate, and additionally in developing a diagnostic regime for viral outbreaks to combat viruses especially the ongoing novel coronavirus (COVID-19).


Subject(s)
COVID-19 , Viruses , Humans , Magnetic Phenomena , Magnetics , SARS-CoV-2 , Viruses/genetics
SELECTION OF CITATIONS
SEARCH DETAIL