A critical challenge in producing an antibody-based assay with the highest reproducibility and sensitivity is the strategy to immobilize antibodies to solid phase. To date, numerous methods of antibody immobilization were reported but each was subjected to its advantages and limitations. The current study proposes a new potential antibody binding protein, the human neonatal fragment crystallizable (Fc) receptor. This protein has shown its high affinity to the Fc of antibody either in vivo or in vitro. Human neonatal Fc receptor is a heterodimer constructed by p51 α-heavy chain and β2-microglobulin light chain; however, the binding sites toward the antibody are located in the p51 α-heavy chain. Hence, vector cloning and recombinant protein expression were carried out to express the p51 α-heavy chain of the human neonatal Fc receptor (hFcRn-α). The recombinant protein expressed, hFcRn-α, was adopted to pin rabbit IgG against hepatitis B virus surface antigen to a solid phase. A sandwich enzyme-linked immunosorbent assay was further developed to evaluate the efficiency of hFcRn-α-directed immobilization in antigen detection. The result was compared with the conventional physical adsorption method. The findings demonstrated that human neonatal Fc receptor was efficient in pinning antibodies and generating higher signals compared with the physical adsorption of antibody.
Ganoderma neo-japonicum is a well-known medicinal mushroom in Asian countries. However, scientific validations on its curative activities are confined to cirrhosis and diabetes. In this study, the anticancer properties of G. neo-japonicum were evaluated using cellular and computational models. The ethanolic extract (EtOH) with a promising inhibitory effect was fractionated into four different fractions: hexane (Hex), chloroform (Chl), butanol (Btn), and aqueous (Aq). The active fractions were then subjected to cell apoptosis assessment and phytochemical profiling. Molecular docking was conducted to elucidate the affinity of selected constituents towards antiapoptotic Bcl-2 protein. The butanol fraction showed the highest antioxidant activities as well as total phenolic content. Both hexane and chloroform fractions exerted a potent cytotoxic effect on colonic carcinoma cells through the induction of apoptosis. Phytochemical analysis revealed that the chloroform fraction is terpenoid enriched whereas the hexane fraction comprises predominantly sterol constituents. Stellasterol and 1,25-dihydroxyvitamin D3 3-glycoside were demonstrated to have a high affinity towards Bcl-2 protein. Overall, G. neo-japonicum can be considered as a compelling therapeutic candidate for cancer treatment.
Anesthesia-related drugs cause various side effects and health-related illnesses after surgery. In particular, neurogenerative disorder is a common problem of anesthesia-related drugs. A patient gets anesthesia as a requirement of the preoperative evaluation to diagnose the medical illness, which is caused by anesthetic drug treatment. Different blood-based biomarkers help in identifying the changes appearing in patients after anesthesia treatment. Among them, tau protein is a sensitive biomarker of neurodegenerative diseases, and the fluctuations in tau proteins are highly associated with various diseases. Furthermore, researchers have found unstable levels of tau protein after the anesthesia process. The current research has focused on quantifying tau protein via impedance spectroscopy to identify the problems caused by anesthesia-related drugs. An impedance spectroscopy electrode was modified into a multiwalled carbon nanotube, and an amine-ended aptamer was then attached. This electrode surface was used to quantify the tau protein level and reached the detection limit of 1 fM. The determination coefficient was found to be y = 369.93x + 1144.9, with R2 = 0.9846 in the linear range of 1 fM-1 nM. Furthermore, tau protein spiked human serum was clearly identified on the immobilized aptamer surface, indicating the specific detection.
Acute myocardial infarction (AMI) is one of the leading causes of death worldwide. Cardiac troponin I (cTn1) is a commonly used biomarker for the diagnosis of AMI. Although there are various detection methods for the rapid detection of cTn1 such as optical, electrochemical, and acoustic techniques, electrochemical aptasensing techniques are commonly used because of their ease of handling, portability, and compactness. In this study, an electrochemical cTn1 biosensor, MoS2 nanoflowers on screen-printed electrodes assisted by aptamer, was synthesized using hydrothermal technique. Field emission scanning electron microscopy revealed distinct 2D nanosheets and jagged flower-like 3D MoS2 nanoflower structure, with X-ray diffraction analysis revealing well-stacked MoS2 layers. Voltammetry aptasensing of cTn1 ranges from 10 fM to 1 nM, with a detection limit at 10 fM and a sensitivity of 0.10 nA µM-1 cm-2 . This is a ∼fivefold improvement in selectivity compared with the other proteins and human serum. This novel aptasensor retained 90% of its biosensing activity after 6 weeks with a 4.3% RSD and is a promising high-performance biosensor for detecting cTn1.
An oligonucleotide DNA probe has been developed for the application in the DNA electrochemical biosensor for the early diagnosis of coronavirus disease (COVID-19). Here, the virus microRNA from the N-gene of severe acute respiratory syndrome-2 (SARS-CoV-2) was used for the first time as a specific target for detecting the virus and became a framework for developing the complementary DNA probe. The sequence analysis of the virus microRNA was carried out using bioinformatics tools including basic local alignment search tools, multiple sequence alignment from CLUSTLW, microRNA database (miRbase), microRNA target database, and gene analysis. Cross-validation of distinct strains of coronavirus and human microRNA sequences was completed to validate the percentage of identical and consent regions. The percent identity parameter from the bioinformatics tools revealed the virus microRNAs' sequence has a 100% match with the genome of SARS-CoV-2 compared with other coronavirus strains, hence improving the selectivity of the complementary DNA probe. The 30 mer with 53.0% GC content of complementary DNA probe 5' GCC TGA GTT GAG TCA GCA CTG CTC ATG GAT 3' was designed and could be used as a bioreceptor for the biosensor development in the clinical and environmental diagnosis of COVID-19.
Results from the present study have shown that the ionic species of buffers, pH values and reaction temperature can affect the enzyme unit activities and product specificity of Toruzyme (Novo Nordisk A/S Bagsvaerd, Denmark) CGTase (cyclodextrin glucanotransferase). Applying a similar reaction environment (acetate buffer, pH 6.0; temperature, 60 degrees C), the CGTase was found to be capable of producing pre dominantly beta-cyclodextrin from either raw or gelatinized sago (Cycas revoluta) starch. Changing the buffer from acetate to phosphate reduced the yield of beta-cyclodextrin from 2.48 to 1.42 mg/ml and also affected the product specificity, where production of both alpha- and beta-cyclodextrins were more pronounced. The decrease in the production of cyclodextrins in phosphate buffer was significant at both pH 6.0 and 7.0. However, changing the buffer to Tris/HCl (pH 7.0) showed a significant increase in beta-cyclodextrin production. Increasing the ionic strength of sodium acetate and Tris/HCl buffers at pH 6.0 and 7.0 to equivalent ionic strength of phosphate buffers showed no significant effects on cyclodextrin production. Higher yield of cyclodextrins at pH 7.0 when Tris/HCl was used might be due to the binding of chloride ions at the calcium-binding sites of the CGTase, resulting in the shift of the optimum pH close to physiological environment, leading to an increase in the activities and specificity.
Major concern about the presence of fluoranthene, which consists of four fused benzene rings, in the environment has been raised in the past few years due to its toxic, mutagenic, and persistent organic pollutant properties. In this study, we investigated the removal of fluoranthene under static and agitated conditions. About 89% fluoranthene was removed within 30 days under the agitated condition, whereas under the static condition, only 54% fluoranthene was removed. We further investigated the behavior and mechanism of fluoranthene biosorption and biotransformation by Pleurotus eryngii F032 to accelerate the elimination of fluoranthene. The optimum conditions for the elimination of fluoranthene by P. eryngii F032 included a temperature of 35 °C, pH 3, 0.2% inoculum concentration, and a C/N ratio of 16. Under these conditions at the initial fluoranthene concentration of 10 mg/L, more than 95% of fluoranthene was successfully removed within 30 days. Of those factors influencing the biodegradation of fluoranthene, salinity, glucose, and rhamnolipid content were of the greatest importance. Degradation metabolites identified using gas chromatography-mass spectrometry were 1-naphthalenecarboxylic acid and salicylic acid, suggesting possible metabolic pathways. Finally, it can be presumed that the major mechanism of fluoranthene elimination by white-rot fungi is to mineralize polycyclic aromatic hydrocarbons via biotransformation enzymes like laccase.
Researches have proved that increasing level of prostate-specific antigen (PSA) is an indicator for the progression of prostate cancer. The present study was focused to determine the PSA level by using anti-PSA antibody conjugated iron oxide nanoparticles, as the probe immobilized on the gap-fingered electrode sensing surface. The detection limit and sensitivity were found at the level of 1.9 pg/mL on the linear regression curve (y = 1.6939x - 0.5671; R² = 0.9878). A dose-dependent liner range was found from 1.9 until 60 pg/mL. Further, PSA was spiked in human serum and did not affect the interaction of PSA and its antibody. This method of detection quantifies the level of PSA, which helps to diagnose prostate cancer at its earlier stage.
Overuse of antibiotics has led to the development of multi drug resistant strains. Antibiotic resistance is a major drawback in the biomedical field since medical implants are prone to infection by biofilms of antibiotic resistant strains of bacteria. With increasing prevalence of antibiotic resistant pathogenic bacteria, the search for alternative method is utmost importance. In this regard, magnetic nanoparticles are commonly used as a substitute for antibiotics that can circumvent the problem of biofilms growth on the surface of biomedical implants. Iron oxide nanoparticles (IONPs) have unique magnetic properties that can be exploited in various ways in the biomedical applications. IONPs are engineered employing different methods to induce surface functionalization that include the use of polyethyleneimine and oleic acid. IONPs have a mechanical effect on biofilms when in presence of an external magnet. In this review, a detailed description of surface engineered magnetic nanoparticles as ideal antibacterial agents is provided, accompanied by various methods of literature review. This article is protected by copyright. All rights reserved.
This study demonstrated the terminated sialo-sugar chains (Neu5Acα2,6Gal and Neu5Acα2,3Gal) mediated specificity enhancement of influenza virus and chicken red blood cell (RBC) by hemagglutination assay. These glycan chains were immobilized on the gold nanoparticle (GNP) to withhold the higher numbers. With the preliminary optimization, a clear button formation with 0.5% RBC was visualized. On the other hand, intact B/Tokio/53/99 with 750 nM hemagglutinin (HA) displayed a nice hemagglutination. The interference on the specificity of RBC and influenza virus was observed by anti-influenza aptamer at the concentration 31 nM, however, there is no hemagglutination prevention was noticed in the presence of complementary aptamer sequences. Spiking GNP conjugated Neu5Acα2,6Gal or Neu5Acα2,3Gal or a mixture of these two to the reaction promoted the hemagglutination to 63 folds higher with 12 nM virus, whereas under the same condition the heat inactivated viruses were lost the hemagglutination. Neuraminidases from Clostridium perfringens and Arthrobacter ureafaciens at 0.0025 neuraminidase units are able to abolish the hemagglutination. Other enzymes, Glycopeptidase F (Elizabethkingia meningoseptica) and Endoglycosidase H (Streptomyces plicatus) did not show the changes with agglutination. Obviously, sialyl-Gal-terminated glycan conjugated GNP amendment has enhanced the specificity of erythrocyte-influenza virus and able to be controlled by aptamer or neuraminidases. This article is protected by copyright. All rights reserved.
Prostate cancer is one of the predominant cancers affecting men and has been widely reported. In the past, various therapies and drugs have been proposed to treat prostate cancer. Among these treatments, gene therapy has been considered to be an optimal and widely applicable treatment. Furthermore, due to the increased specificity of gene sequence complementation, the targeted delivery of complementary gene sequences may represent a useful treatment in certain instances. Various gene therapies, including tumor-suppressor gene therapy, suicide gene therapy, immunomodulation gene therapy and anti-oncogene therapies, have been established to treat a wide range of diseases, such as cardiac disease, cystic fibrosis, HIV/AIDS, diabetes, hemophilia, and cancers. To this end, several gene therapy clinical trials at various phases are underway. This overview describes the developments and progress in gene therapy, with a special focus being placed on prostate cancer.
A high-performance interdigitated electrode (IDE) biosensing surface was reported here by utilizing self-assembled silica nanoparticle (SiNP). The modified surface was used to evaluate the complementation of hairpin forming region from Mitoxantrone resistance gene 7 (MXR7; liver cancer-related short gene). The conjugated SiNPs on 3-aminopropyl triethoxysilane functionalization were captured with probe sequence on IDE biosensing surface. The physical and chemically modified surface was used to quantify MXR7 and an increment in the current response upon complementation was noticed. Limit of target DNA detection was calculated (1-10 fM) and this label-free detection is at the comparable level to the fluorescent-based sensing. A linear regression was calculated [y = 0.243x - 0.0773; R² = 0.9336] and the sensitivity was 1 fM on the linear range of 1 fM to 10 pM. With the strong attachment of capture DNA on IDE through SiNP, the surface clearly discriminates the specificity (complementary) versus nonspecificity (complete-, single-, and triple-mismatched sequences). This detection strategy helps to determine liver cancer progression and the similar strategy can be followed for other gene sequence complementation.
Nanomaterial on the sensing area elevates the biomolecular immobilization by its right orientation with a proper alignment, and zeolite is one of the suitable materials. In this research, the zeolite nanoparticles were synthesized using rice hush ash as the basic source and the prepared zeolite by the addition of sodium silicate was utilized to attach antibody as a probe on a gap-fingered dielectrode surface to identify the colon cancer biomarker, "colon cancer-secreted protein-2" (CCSP-2). Field Emission Scanning Electron Microscopy and Field Emission Transmission Electron Microscopy images confirmed the size of the nanoparticle to be ∼15 nm and the occurrence of silica and alumina. Zeolite was modified on the electrode surface through the amine linker, and then anti-CCSP-2 was attached by an aldehyde linker. On this surface, CCSP-2 was detected and attained the detection limit to be 3 nM on the linear regression curve with 3-5 nM of CCSP-2. Estimated by the determination coefficient of y = 2.3952x - 4.4869 and R2 = 9041 with 3δ (n = 3). In addition, control proteins did not produce the notable current response representing the specific sensing of CCSP-2. This research is suitable to identify CCSP-2 at a lower level in the bloodstream under the physiological condition of a colon cancer patient.
Detection of asthma by a suitable biomarker is mandatory for the early identification, which helps in providing a right medication for the complete cure. Interleukins (ILs) have played a major role in asthma; in particular IL-8 is highly correlated with severe asthma. This research was focused on to detect IL-8 level by its partner antibody on a microgapped dual electrodes sensor. The sensing surface was modified into graphene oxide (GO), and an antibody was fixed by using the amine-aldehyde linker. GO enhanced the antibody immobilization and the consequence electric current flow upon interacting with IL-8. The detection limit of IL-8 was reached to 10 pg/mL in a linear range from 1 to 10,000 pg/mL with the regression of y = 0.7246x - 0.906 (R² = 0.9758); further, the sensitivity falls at 1 pg/mL. The surface does not show the antifouling effect with control antibody, and proteins, indicating the specific IL-8 detection. The detection of IL-8 helps in diagnosing and solving the related problems of asthmatic patients.
Recent developments in nanotechnology promoted the production of nanomaterials with various shapes and sizes by utilizing interdisciplinary researches of biology, chemistry, and material science toward the clinical perspectives. In particular, gold and silver (Ag) are noble metals that exhibit tunable and unique plasmonic properties for the downstream applications. Ag exhibits higher thermal and electrical conductivities, and more efficient in the electron transfer than gold with sharper extinction bands. In addition, modified Ag nanoparticle is more stable in water and air. With all these above features, Ag is an attractive tool in various fields, including diagnosis, drug delivery, environmental, electronics, and as antimicrobial agent. In particular, applications of Ag nanoparticle in the fields of biosensor and imaging are prominent in recent days. Enhancing the specific detection of clinical markers with Ag nanoparticle has been proved by several studies. This review discussed the constructive application of Ag nanoparticle in biosensor and bioimaging for the detection of small molecule to larger whole cell in the perspectives of diagnosing diseases.
This study presents a novel sulfur-doped graphitic carbon nitride (S@g-C3 N4 ) with a wider potential range as electrocatalyst for electrochemical sensor application. The S@g-C3 N4 nanosheets were successfully prepared with a ball milling method by mixing appropriate molar concentration required precursors. The as-synthesized heteroatom-doped graphitic carbon nitride is characterized by spectroscopic techniques including PL, DRS-UV, FT-IR, and Brunauer-Emmett-Teller equation. The morphological features were studied by FE-SEM and HR-TEM analysis. Chit-S@g-C3 N4 -modified glassy carbon electrode (GCE) was employed for the electrochemical detection of omeprazole (OMZ) use in drug formulations. We have noted an oxidation peak current response at a potential of +0.8 V versus Ag/AgCl in PBS medium (0.1 M, pH 7.0). Differential pulse voltammetry amperometry experimental method can be used to measure the concentration of OMZ for quantitative studies in known samples. Under the optimized experimental condition, the calibration plot was constructed by plotting the peak currents versus OMZ in the linear ranges from 6.0 × 10-7 to 26 × 10-5 M. The linear regression equation is estimated to be Ip (μA) = 0.9518 (C/μM) + 0.3340 with a good correlation coefficient of 0.9996. The lower determination limit was found to be 20 nM and the current sensitivity was calculated (31.722 μA μM-1 cm-2 ). The developed sensor was utilized successfully to determine the OMZ concentration in drug formulations and biological fluids. These results revealed that the Chit-S@g-C3 N4 -modified GCE showed excellent electroanalytical performance for the detection of OMZ at a low LOD, wider linear range, high sensitivity, good reproducibility, long-term storage stability, and selectivity with an acceptable relative standard deviation value.
We demonstrate a green chemistry approach to synthesize narrow-sized zerovalent iron (nZVI) nanoparticles using Artocarpus heterophyllus Lam. leaf extract as reducing and capping agent. The produced nZVI was characterized by various instrumental methods including ultraviolet-visible spectra, transmission electron microscopy, vibrating sample magnetometer (VSM), X-ray diffraction, and Fourier transform infrared spectroscopy. Based on the electron microscopy observations, the particle size was estimated to be ∼30 nm. In VSM, the saturation point of magnetization was observed to be 0.6 emu g-1 under a magnetic field of 0 ± 30 kOe. The synthesized nZVI was amorphous in nature as per the XRD results. The catalytic activity of the nZVI was employed for the catalytic reduction of 4-nitrophenol (4-NP) and decoloration of textile dyes such as methylene blue, methyl orange, and malachite green, respectively. The proposed nZVI synthesis method exhibited better catalytic performance toward reduction of 4-NP and degradation of dyes within 4 min for 0.1 mg of catalyst. Moreover, the synthesized catalyst nZVI can be recoverable and reutilized in many cycles without loss of its significant catalytic activity. The synthesized nZVI could be a promising material to treat industrial wastewater via profitable, sustainable, and ecofriendly approaches.
Breast cancer has been reported to be high in its incidence with women, and early identification of breast cancer helps to improve and provide an effective treatment. Tumor markers are active substances; in particular, human epidermal growth factor receptor 2 (HER2) is over-expressed at the level of 20%-30%. This research work developed a highly sensitive HER2 biosensor on the interdigitated electrode (IDE) by using aptamer as a detection probe. To enhance the analytical performances, aptamer was attached to the gold nanoparticle and immobilized on the IDE through a chemical linker [(3-aminopropyl)triethoxysilane]. On the aptamer conjugation, HER2 was quantified through current-volt measurements, and the limit of detection of HER2 was calculated as 1 pg/mL on a linear range from 0.1 to 3000 pg/mL at an R2 (regression coefficient) of 0.9657. Further, a selective performance with human serum increased the current responses by increasing HER2 concentrations. Specific experiments with control protein and complementary aptamer sequence failed to enhance the current responses. This HER2 biosensor reflects the occurrence of breast cancer at its lower abundance and helps to identify the associated complications.
Infectious diseases, caused by pathogenic microorganisms such as bacteria, viruses, parasites, or fungi, are crucial for efficient disease management, reducing morbidity and mortality rates and controlling disease spread. Traditional laboratory-based diagnostic methods face challenges such as high costs, time consumption, and a lack of trained personnel in resource-poor settings. Diagnostic biosensors have gained momentum as a potential solution, offering advantages such as low cost, high sensitivity, ease of use, and portability. Nanobiosensors are a promising tool for detecting and diagnosing infectious diseases such as coronavirus disease, human immunodeficiency virus, and hepatitis. These sensors use nanostructured carbon nanotubes, graphene, and nanoparticles to detect specific biomarkers or pathogens. They operate through mechanisms like the lateral flow test platform, where a sample containing the biomarker or pathogen is applied to a test strip. If present, the sample binds to specific recognition probes on the strip, indicating a positive result. This binding event is visualized through a colored line. This review discusses the importance, benefits, and potential of nanobiosensors in detecting infectious diseases.
Smoking, passive smoking, and nonsmoking are conditions that give different degrees of stress to the body. In this study, a proteomic technique was used to analyze differentially urinary protein expression between these three groups of subjects. Urinary proteins were precipitated using ammonium sulfate followed by separation according to molecular weights using SDS-PAGE. The gel was stained by Coommassie blue, and the image of the gel was captured for the comparison study. The protein bands that were consistently detected but expressed at different intensity between the smokers and nonsmokers were targeted for further analysis. Three targeted protein bands were excised from the gel, consisting of a unique protein band of smokers and a pair of differentially expressed protein bands from smokers and nonsmokers. The proteins were digested in gel by trypsin. The tryptic peptides were analyzed with ultra performance liquid chromatography-tandem mass spectrometry. Protein identity was determined by the product ion spectrum in the MS/MS scan. Four unique proteins from the smokers, namely, pancreatic alpha amylase, proepidermal growth factor, protein 4.1, and prostatic acid phosphatase, were found to be potential urinary biomarkers to indicate smoking status of a person.