Lactate is a useful analytical indicator in various fields. The lactate monitoring benefits from ... more Lactate is a useful analytical indicator in various fields. The lactate monitoring benefits from evaluating the body's condition, as excessive muscle use or fatigue can result in injury. Further, it is useful for alerting to emergencies like haemorrhage, hypoxia, respiratory distress, and sepsis. Additionally, the determination of the food's lactate level is very important in examining freshness, storage stability, and fermentation degree. Given such benefits, the determination of lactate in various samples has been widely explored, especially using electrochemical sensor technology. Despite enzymatic sensors being the focus of numerous studies, enzyme-free platforms have gained focus over the last few years to address the matter of enzyme stability. This review article respectfully offers an overview of the concepts, applications, and recent advances of electrochemical lactate detection platforms. A comparison of hot research for enzymatic and enzyme-free lactate sensors in terms of electrode surface engineering, enzymes and their immobilisation matrices, and several analytical parameters, including linear dynamic range, the limit of detection, sensitivity, and stability, have been discussed. In addition, future perspectives have been highlighted in this review. Heru Agung Saputra and Md Mobarok Karim contributed equally to this work. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.
A disposable dual-output biosensor to detect program death-ligand 1 (PD-L1) was developed for imm... more A disposable dual-output biosensor to detect program death-ligand 1 (PD-L1) was developed for immunotherapy progress monitoring and early cancer detection in a single experimental setup. The aptamer probe was assembled on rGO composited with carboxylated terthiophene polymer (rGO-pTBA) to specifically capture PD-L1 protein labeled with a new redox mediator, ortho-amino phenol para sulphonic acid, for amperometric detection. Each sensing layer was characterized through electrochemical and surface analysis experiments, then confirmed the sensing performance. The calibration plots for the standard PD-L1 protein detection revealed two dynamic ranges of 0.5-100.0 pM and 100.0-500.0 pM, where the detection limit was 0.20 ± 0.001 pM (RSD ≤5.2%) by amperometry. The sensor reliability was evaluated by detecting A549 lung cancer cell-secreted PD-L1 and clinically relevant serum levels of soluble PD-L1 (sPD-L1) using both detection methods. In addition, therapeutic trials were studied through the quantification of sPD-L1 levels for a small cohort of lung cancer patients. A significantly higher level of sPD-L1 was observed for patients (221.6-240.4 pM) compared to healthy individuals (16.2-19.6 pM). After immunotherapy, the patients' PD-L1 level decreased to the range of 126.7-141.2 pM. The results indicated that therapy monitoring was successfully done using both the proposed methods. Additionally, based on a comparative study on immune checkpoint-related proteins, PD-L1 is a more effective biomarker than granzyme B and interferon-gamma.
The separation of rare-earth elements (REEs) has increasingly developed, especially using a compl... more The separation of rare-earth elements (REEs) has increasingly developed, especially using a complexing ligand of dibutyl dithiophosphate (DBDTP) that has numerous advantages as an extractant in the extraction process. Through technology development, this separation utilizes computational chemistry design to scheme the DBDTP ligand and its derivatives. One of the computational chemistry applications is a quantitative structure-property relationship (QSPR), which is useful for designing ligand derivatives by calculating molecular descriptors and connecting molecular structure with its physicochemical properties. In the present study, we aimed to get a dominant factor affecting complex stability formed from the REEs with DBDTP ligands and the REEs with DBDTP derivative ligands using principal component analysis for the QSPR study. The analysis results demonstrated that the stability of gadolinium, terbium, and dysprosium complex compounds was influenced by seven, seven, and six factors with a total variance of 93.93, 93.17, and 91.63%, respectively.
Journal of Research Updates in Polymer Science, 2024
Chitosan is an abundant natural biopolymer widely used in industrial and pharmaceutical applicati... more Chitosan is an abundant natural biopolymer widely used in industrial and pharmaceutical applications. It stands out for its remarkable biodegradability, biocompatibility, and versatility. Herein, we tried to extract chitosan from mud crab (Scylla spp.), a seafood waste abundantly found in Bangladesh's growing crab farming industry, via a simple low-cost production route. At first, chitin was extracted from crab shells through demineralization and deproteinization to eliminate minerals and proteins. The chitosan biopolymer was then obtained by deacetylation of purified chitin. To evaluate its physicochemical properties, the as-prepared chitosan was characterized by different analyses, such as water and fat binding capacity, solubility, viscosity, molecular weight, fourier transform-infrared, thermogravimetric, scanning electron microscopy, and ash content analysis. The results showed that the crab shell contains around 26.8% chitosan by dry weight, making it an excellent raw material for the massive production of the natural biopolymer chitosan. The prepared chitosan showed fat and water binding capacities of 200-300% and ~680.9%, respectively. Furthermore, it was highly soluble in 1% acetic acid and had an ash content of about 33.7%. Convincingly, the produced chitosan showed great physiochemical properties making it suitable for biomass efficiency, sustainable development, revenue generation, and biomedical applications. In addition, the recycling of seafood waste into a valued product is beneficial to help keep the environment clean, which is among the sustainability goals in Bangladesh and globally.
The purpose of this research was to describe the effectiveness of scientific approach to the stud... more The purpose of this research was to describe the effectiveness of scientific approach to the students' skill in evaluating the chemical equilibrium material. The subject of this research was all of the students in XI IPA SMA Negeri 1 Bangunrejo in odd semester 2013-2014. In addition, XI IPA 1 and XI IPA 2 act as sample. The research method was quasi experiment with pretest-posttest control group design. The effectiveness of this method was measured through significant n-Gain between the control class and experimental class. The result showed that the n-Gain for evaluating in control class is 0,249 while the score for experimental class is 0,52. Based on the hypothesis testing, the researcher concluded that, statistically, there is a significant improvement between the class which was taught through traditional way and the class which was taught through scientific approach. This result showed that the scientific approach is an effective method to be used in the learning of chemical equilibrium material.
Bacillus subtilis is a bacterial contaminant widely discovered in laboratories and used in educat... more Bacillus subtilis is a bacterial contaminant widely discovered in laboratories and used in educational needs. Synthetic media are relatively expensive, which makes it difficult for microbiology laboratories to meet large-scale bacterial growth media demands. This has encouraged researchers to find alternative media with cheaper and easily available prices, namely Mung Beans, which are known to contain protein nutrients that are good for bacterial growth, which is as much as 24%. The purpose of this study was to determine the potential of mung beans' alternative media as a medium for bacterial growth. This research is a descriptive study and the sample used is 1 tube of a pure isolate of Bacillus subtilis. The variable of this research is mung beans as an alternative medium for the growth of Bacillus subtilis. The results were obtained by observed macroscopically and microscopically, followed by a carbohydrate fermentation test and an IMViC test. Then showed that the colonies growing on the alternative medium of mung beans were in accordance with the characteristics of the colonies growing on Nutrient Agar medium (control), which indicated that these characteristics were Bacillus subtilis. Based on the research that has been done, it can be concluded that there is a qualitative growth of Bacillus subtilis in mung beans alternative media, which means that mung beans alternative media has the potential as a growth medium for Bacillus subtilis.
Utilization of Articulate Storyline as Interactive Learning Media to Improve the Study Motivation... more Utilization of Articulate Storyline as Interactive Learning Media to Improve the Study Motivation of College Students. A teacher is required to be able to develop a learning approach that is in line with the today's student learning styles. This study was aimed at finding out the utilization of articulate storyline to increase the student motivation in the interactive learning of the history of chemistry. The research subjects were 66 college students divided into groups A and B with 33 students for each. The research method was the research interviews (a qualitative research), where the problem formulation was if (or not) use of the articulate storyline as interactive learning media can improve the student learning motivation. The instruments for the data collection were the observation sheets. 75.8, 15.2, and 9.1% of the students in group A stated that the articulate storyline improved the study motivation in very high, high, and the medium levels, respectively. Meanwhile, 33.3, 54.5, and 9.1% of group B students declared that their learning motivation improved in very high, high, and the medium levels, respectively. In addition, 3% of the students in this group revealed that the articulate storyline affected their learning motivation in the low level. Conclusively, the interactive learning media of the articulate storyline could improve the learning motivation of Chemical Education students on the history of chemistry.
The development of a simple and fast cancer detection method is crucial since early diagnosis is ... more The development of a simple and fast cancer detection method is crucial since early diagnosis is a key factor in increasing survival rates for lung cancer patients. Among several diagnosis methods, the electrochemical sensor is the most promising one due to its outstanding performance, portability, real-time analysis, robustness, amenability, and cost-effectiveness. Conducting polymer (CP) composites have been frequently used to fabricate a robust sensor device, owing to their excellent physical and electrochemical properties as well as biocompatibility with nontoxic effects on the biological system. This review brings up a brief overview of the importance of electrochemical biosensors for the early detection of lung cancer, with a detailed discussion on the design and development of CP composite materials for biosensor applications. The review covers the electrochemical sensing of numerous lung cancer markers employing composite electrodes based on the conducting polyterthiophene, poly(3,4-ethylenedioxythiophene), polyaniline, polypyrrole, molecularly imprinted polymers, and others. In addition, a hybrid of the electrochemical biosensors and other techniques was highlighted. The outlook was also briefly discussed for the development of CP composite-based electrochemical biosensors for POC diagnostic devices.
An ultrasensitive electrochemical aptasensor was designed with a bifunctionalized conducting poly... more An ultrasensitive electrochemical aptasensor was designed with a bifunctionalized conducting polymer nanobioconjugate to monitor patients' progress in cancer immunotherapy by detecting IFN-γ. The sensing probe was fabricated by covalently immobilizing aptamer on a polyterthiophene benzoic acid composited with multi-walled carbon nanotube/Au nanoparticles. The nanobioconjugate was prepared through the self-assembly of bifunctionalized terthiophene aminobenzoic acid (TABA) onto AuNPs then covalently attached with a redox indicator and an antibody on the amine and carboxyl groups of TABA, respectively. At the optimized condition, the sensor detected IFN-γ in the concentration range of 0.5 fM-100 pM with a detection limit of 0.46 ± 0.006 fM (RSD ≤5.1%). The sensor was applied to monitor the extracellular release of IFN-γ by peripheral blood mononuclear cells and the IFN-γ levels in patients' serum before and after immunotherapy. We observed a low concentration of 0.07 ± 0.004 pM (RSD ≤5.6%) before therapy, which increased significantly to 0.43 ± 0.02 pM (RSD ≤5.1%) after immunotherapy. Meanwhile, a high IFN-γ level of 0.67 ± 0.04 pM (RSD ≤6.2%) was detected in healthy controls. In addition, our study showed IFN-γ is a more effective biomarker for predicting patients' response to blockade therapy as compared to granzyme B.
Electrochemical sensor technology is an integral part of modern analytical chemistry that has att... more Electrochemical sensor technology is an integral part of modern analytical chemistry that has attracted great attention. It is multifaceted and rapidly progressing because of its high demand and continuous technological advancements. Electrochemical sensors offer several advantages over traditional analytical methods, including selectivity, sensitivity, robustness, ease of operation, short-time measurement, portability, low cost, etc. Interestingly, some of such features are possible to engineer toward a better performance improvement by adjusting to the assay needs. This review article comprehensively discusses the components, configuration, and tailoring of electrochemical sensors. The electrode surface modification and its importance in performance enhancement, especially in terms of selectivity and sensitivity, are discussed. The immobilization strategies, their advantages, and limitations, as well as the influential factors in surface engineering, are also highlighted. In addition, state-of-the-art electrochemical sensors either based on the immobilization matrices or recognition elements for a diverse range of target analytes are discussed. Challenges and future aspects are briefly reviewed. The author believes the insights presented here will spark extra efforts to further understand and in turn, develop electrochemical sensors.
Lung cancer is among the most life-threatening diseases, as it is by far the leading cause of dea... more Lung cancer is among the most life-threatening diseases, as it is by far the leading cause of death around the globe. However, plentiful studies have been reported with satisfactory results employing electrochemical biosensors, which make this method popular in lung cancer diagnosis. In assembling the sensing platforms, different materials of the sensor interfaces are utilized in electrode surface modification to enhance performance. A natural biopolymer chitosan (CS) is an outstanding material for the development of electrochemical biosensors. The unique physiochemical features exhibited by CS facilitate the preservation of its innovative traits and promote its secure adhesion onto the electrode surface. It also has inherent characteristics, such as high adsorption ability, good biocompatibility, eco-friendliness nature, greater heat stability, improved permeability, mechanical potency, outstanding layer-forming capability, and ease of availability. In combination with conductive materials, CS enables the modified electrodes to perform the best analytical results. This review is focused on the importance of CS in sensor configuration, advancements of CS-based electrochemical biosensors for detecting lung cancer biomarkers, and future prospects.
Rare earth elements are a set of seventeen metallic elements, which is an essential part of many ... more Rare earth elements are a set of seventeen metallic elements, which is an essential part of many high-tech devices. Hence, analysis and/or separation of the rare earth elements from their mineral become crucial. A novel analysis method combining ultraviolet-visible spectroscopic and multivariate analysis was developed to determine middle rare earth elements quickly and simultaneously. The data collected from ultraviolet-visible spectroscopic were analyzed by multivariate analysis. The results showed that the developed method has good accuracy and precision with a detection limit of 1.375 (± 0.012), 0.332 (± 0.004), 42.117 (± 0.200), 1.767 (± 0.011), and 0.576 (± 0.002) ppm, respectively for samarium, europium, gadolinium, terbium, and dysprosium. The interference effect of ammonium iron(II) sulfate hexahydrate, manganese(III) sulfate hydrate, calcium carbonate, sodium carbonate, and lead(II) nitrate were examined. The reliability of the proposed method was evaluated using monazite s...
According to regulation number 722/MENKES/Per/IX/88 of the Minister of Health of the Republic of ... more According to regulation number 722/MENKES/Per/IX/88 of the Minister of Health of the Republic of Indonesia, Rhodamine B is one of the dangerous dyes, and its use in food products is prohibited. Rhodamine B can cause adverse health effects including irritation, impaired liver function, and liver cancer. Although it has been banned, the use of Rhodamine B is still prevalent in the community's food supply, including shrimp paste. This can be observed in some of the shrimp pastes sold at the Ciroyom market in Bandung, which are bright red, uneven, and comprised of lumps. This study aims to determine the Rhodamine B content of shrimp paste sold at Ciroyom Market in Bandung, West Java, Indonesia. This research is descriptive in nature and employed a total sampling technique. Rhodamine B was analyzed in ten samples of commercially available red shrimp paste using a UV-Vis Spectrophotometer with a 565 nm wavelength. The results indicate that Rhodamine B was found in all samples, with co...
Granzyme B (GzmB) is a cytotoxic protease found in the granules of natural killer (NK) cells and ... more Granzyme B (GzmB) is a cytotoxic protease found in the granules of natural killer (NK) cells and cytotoxic T lymphocytes (CTLs), which participates in inducing apoptosis of target cells for NK cells and cytotoxic CD8+ lymphocytes [1]. GzmB is the major effector of the CTLs and NK cells in its killing attack on cancer cells, although the level of GzmB expression and its cytotoxic potential decrease significantly in the presence of cancer. This decrement is due to a ‘pro-cancer’ environment, where the cancer cells secrete soluble mediators that could inhibit and thus contribute to the decreased GzmB by CD8+ T cells and a reduction in their ability to cause apoptosis of the cancer cells. Once GzmB is secreted from cytotoxic cells, it can be discovered in two different host compartments, namely inside the target cell or extracellularly [2]. Due to this, the change of GzmB level in blood plasma may serve as indication of the patient’s cancer cure progress. Hence, we developed a disposabl...
A disposable amperometric biosensor with a dual monomers-based bioconjugate was developed for gra... more A disposable amperometric biosensor with a dual monomers-based bioconjugate was developed for granzyme B (GzmB) detection and for monitoring of the cancer progression of patients before and after immunotherapy. The biosensor was fabricated by immobilizing a GzmB monoclonal antibody (Ab1) on a poly3'-(2-aminopyrimidyl)-2,2':5',2''-terthiophene/gold nanoparticle (pPATT/AuNP) layer. The bioconjugate nanoparticles were synthesized through self-assembly of a monomer mixture of 2,2:5,2-terthiophene-3-(p-benzoic acid) (TBA) and PATT onto AuNPs, followed by chemical binding of brilliant cresyl blue (BCB) on TBA and GzmB polyclonal antibody (Ab2) on the PATT layer. Each sensing layer was investigated by surface analysis and electrochemical experiments. The sensor performance was assessed with selectivity, stability, reproducibility, detection limit, and real sample analysis. Under the optimized conditions, the dynamic range of GzmB was in two slopes from 3.0 to 50.0 pg/ml and from 50.0 to 1000.0 pg/ml with a detection limit of 1.75 ± 0.14 pg/ml (RSD ≤5.2%). GzmB monitoring was performed for the patient's serum samples, where a low level of GzmB was observed for lung cancer patients before immunotherapy (10.51 ± 0.99 pg/ml, RSD ≤6.2%), and the level was increased after therapy (17.19 ± 2.22 pg/ml, RSD ≤2.6%). Moreover, a significantly higher level was present in healthy persons (34.40 ± 3.92 pg/ml, RSD ≤1.4%). The cancer progression of patients before and after therapy was evaluated by monitoring GzmB levels in human serum using the proposed sensor.
Lactate is a useful analytical indicator in various fields. The lactate monitoring benefits from ... more Lactate is a useful analytical indicator in various fields. The lactate monitoring benefits from evaluating the body's condition, as excessive muscle use or fatigue can result in injury. Further, it is useful for alerting to emergencies like haemorrhage, hypoxia, respiratory distress, and sepsis. Additionally, the determination of the food's lactate level is very important in examining freshness, storage stability, and fermentation degree. Given such benefits, the determination of lactate in various samples has been widely explored, especially using electrochemical sensor technology. Despite enzymatic sensors being the focus of numerous studies, enzyme-free platforms have gained focus over the last few years to address the matter of enzyme stability. This review article respectfully offers an overview of the concepts, applications, and recent advances of electrochemical lactate detection platforms. A comparison of hot research for enzymatic and enzyme-free lactate sensors in terms of electrode surface engineering, enzymes and their immobilisation matrices, and several analytical parameters, including linear dynamic range, the limit of detection, sensitivity, and stability, have been discussed. In addition, future perspectives have been highlighted in this review. Heru Agung Saputra and Md Mobarok Karim contributed equally to this work. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.
A disposable dual-output biosensor to detect program death-ligand 1 (PD-L1) was developed for imm... more A disposable dual-output biosensor to detect program death-ligand 1 (PD-L1) was developed for immunotherapy progress monitoring and early cancer detection in a single experimental setup. The aptamer probe was assembled on rGO composited with carboxylated terthiophene polymer (rGO-pTBA) to specifically capture PD-L1 protein labeled with a new redox mediator, ortho-amino phenol para sulphonic acid, for amperometric detection. Each sensing layer was characterized through electrochemical and surface analysis experiments, then confirmed the sensing performance. The calibration plots for the standard PD-L1 protein detection revealed two dynamic ranges of 0.5-100.0 pM and 100.0-500.0 pM, where the detection limit was 0.20 ± 0.001 pM (RSD ≤5.2%) by amperometry. The sensor reliability was evaluated by detecting A549 lung cancer cell-secreted PD-L1 and clinically relevant serum levels of soluble PD-L1 (sPD-L1) using both detection methods. In addition, therapeutic trials were studied through the quantification of sPD-L1 levels for a small cohort of lung cancer patients. A significantly higher level of sPD-L1 was observed for patients (221.6-240.4 pM) compared to healthy individuals (16.2-19.6 pM). After immunotherapy, the patients' PD-L1 level decreased to the range of 126.7-141.2 pM. The results indicated that therapy monitoring was successfully done using both the proposed methods. Additionally, based on a comparative study on immune checkpoint-related proteins, PD-L1 is a more effective biomarker than granzyme B and interferon-gamma.
The separation of rare-earth elements (REEs) has increasingly developed, especially using a compl... more The separation of rare-earth elements (REEs) has increasingly developed, especially using a complexing ligand of dibutyl dithiophosphate (DBDTP) that has numerous advantages as an extractant in the extraction process. Through technology development, this separation utilizes computational chemistry design to scheme the DBDTP ligand and its derivatives. One of the computational chemistry applications is a quantitative structure-property relationship (QSPR), which is useful for designing ligand derivatives by calculating molecular descriptors and connecting molecular structure with its physicochemical properties. In the present study, we aimed to get a dominant factor affecting complex stability formed from the REEs with DBDTP ligands and the REEs with DBDTP derivative ligands using principal component analysis for the QSPR study. The analysis results demonstrated that the stability of gadolinium, terbium, and dysprosium complex compounds was influenced by seven, seven, and six factors with a total variance of 93.93, 93.17, and 91.63%, respectively.
Journal of Research Updates in Polymer Science, 2024
Chitosan is an abundant natural biopolymer widely used in industrial and pharmaceutical applicati... more Chitosan is an abundant natural biopolymer widely used in industrial and pharmaceutical applications. It stands out for its remarkable biodegradability, biocompatibility, and versatility. Herein, we tried to extract chitosan from mud crab (Scylla spp.), a seafood waste abundantly found in Bangladesh's growing crab farming industry, via a simple low-cost production route. At first, chitin was extracted from crab shells through demineralization and deproteinization to eliminate minerals and proteins. The chitosan biopolymer was then obtained by deacetylation of purified chitin. To evaluate its physicochemical properties, the as-prepared chitosan was characterized by different analyses, such as water and fat binding capacity, solubility, viscosity, molecular weight, fourier transform-infrared, thermogravimetric, scanning electron microscopy, and ash content analysis. The results showed that the crab shell contains around 26.8% chitosan by dry weight, making it an excellent raw material for the massive production of the natural biopolymer chitosan. The prepared chitosan showed fat and water binding capacities of 200-300% and ~680.9%, respectively. Furthermore, it was highly soluble in 1% acetic acid and had an ash content of about 33.7%. Convincingly, the produced chitosan showed great physiochemical properties making it suitable for biomass efficiency, sustainable development, revenue generation, and biomedical applications. In addition, the recycling of seafood waste into a valued product is beneficial to help keep the environment clean, which is among the sustainability goals in Bangladesh and globally.
The purpose of this research was to describe the effectiveness of scientific approach to the stud... more The purpose of this research was to describe the effectiveness of scientific approach to the students' skill in evaluating the chemical equilibrium material. The subject of this research was all of the students in XI IPA SMA Negeri 1 Bangunrejo in odd semester 2013-2014. In addition, XI IPA 1 and XI IPA 2 act as sample. The research method was quasi experiment with pretest-posttest control group design. The effectiveness of this method was measured through significant n-Gain between the control class and experimental class. The result showed that the n-Gain for evaluating in control class is 0,249 while the score for experimental class is 0,52. Based on the hypothesis testing, the researcher concluded that, statistically, there is a significant improvement between the class which was taught through traditional way and the class which was taught through scientific approach. This result showed that the scientific approach is an effective method to be used in the learning of chemical equilibrium material.
Bacillus subtilis is a bacterial contaminant widely discovered in laboratories and used in educat... more Bacillus subtilis is a bacterial contaminant widely discovered in laboratories and used in educational needs. Synthetic media are relatively expensive, which makes it difficult for microbiology laboratories to meet large-scale bacterial growth media demands. This has encouraged researchers to find alternative media with cheaper and easily available prices, namely Mung Beans, which are known to contain protein nutrients that are good for bacterial growth, which is as much as 24%. The purpose of this study was to determine the potential of mung beans' alternative media as a medium for bacterial growth. This research is a descriptive study and the sample used is 1 tube of a pure isolate of Bacillus subtilis. The variable of this research is mung beans as an alternative medium for the growth of Bacillus subtilis. The results were obtained by observed macroscopically and microscopically, followed by a carbohydrate fermentation test and an IMViC test. Then showed that the colonies growing on the alternative medium of mung beans were in accordance with the characteristics of the colonies growing on Nutrient Agar medium (control), which indicated that these characteristics were Bacillus subtilis. Based on the research that has been done, it can be concluded that there is a qualitative growth of Bacillus subtilis in mung beans alternative media, which means that mung beans alternative media has the potential as a growth medium for Bacillus subtilis.
Utilization of Articulate Storyline as Interactive Learning Media to Improve the Study Motivation... more Utilization of Articulate Storyline as Interactive Learning Media to Improve the Study Motivation of College Students. A teacher is required to be able to develop a learning approach that is in line with the today's student learning styles. This study was aimed at finding out the utilization of articulate storyline to increase the student motivation in the interactive learning of the history of chemistry. The research subjects were 66 college students divided into groups A and B with 33 students for each. The research method was the research interviews (a qualitative research), where the problem formulation was if (or not) use of the articulate storyline as interactive learning media can improve the student learning motivation. The instruments for the data collection were the observation sheets. 75.8, 15.2, and 9.1% of the students in group A stated that the articulate storyline improved the study motivation in very high, high, and the medium levels, respectively. Meanwhile, 33.3, 54.5, and 9.1% of group B students declared that their learning motivation improved in very high, high, and the medium levels, respectively. In addition, 3% of the students in this group revealed that the articulate storyline affected their learning motivation in the low level. Conclusively, the interactive learning media of the articulate storyline could improve the learning motivation of Chemical Education students on the history of chemistry.
The development of a simple and fast cancer detection method is crucial since early diagnosis is ... more The development of a simple and fast cancer detection method is crucial since early diagnosis is a key factor in increasing survival rates for lung cancer patients. Among several diagnosis methods, the electrochemical sensor is the most promising one due to its outstanding performance, portability, real-time analysis, robustness, amenability, and cost-effectiveness. Conducting polymer (CP) composites have been frequently used to fabricate a robust sensor device, owing to their excellent physical and electrochemical properties as well as biocompatibility with nontoxic effects on the biological system. This review brings up a brief overview of the importance of electrochemical biosensors for the early detection of lung cancer, with a detailed discussion on the design and development of CP composite materials for biosensor applications. The review covers the electrochemical sensing of numerous lung cancer markers employing composite electrodes based on the conducting polyterthiophene, poly(3,4-ethylenedioxythiophene), polyaniline, polypyrrole, molecularly imprinted polymers, and others. In addition, a hybrid of the electrochemical biosensors and other techniques was highlighted. The outlook was also briefly discussed for the development of CP composite-based electrochemical biosensors for POC diagnostic devices.
An ultrasensitive electrochemical aptasensor was designed with a bifunctionalized conducting poly... more An ultrasensitive electrochemical aptasensor was designed with a bifunctionalized conducting polymer nanobioconjugate to monitor patients' progress in cancer immunotherapy by detecting IFN-γ. The sensing probe was fabricated by covalently immobilizing aptamer on a polyterthiophene benzoic acid composited with multi-walled carbon nanotube/Au nanoparticles. The nanobioconjugate was prepared through the self-assembly of bifunctionalized terthiophene aminobenzoic acid (TABA) onto AuNPs then covalently attached with a redox indicator and an antibody on the amine and carboxyl groups of TABA, respectively. At the optimized condition, the sensor detected IFN-γ in the concentration range of 0.5 fM-100 pM with a detection limit of 0.46 ± 0.006 fM (RSD ≤5.1%). The sensor was applied to monitor the extracellular release of IFN-γ by peripheral blood mononuclear cells and the IFN-γ levels in patients' serum before and after immunotherapy. We observed a low concentration of 0.07 ± 0.004 pM (RSD ≤5.6%) before therapy, which increased significantly to 0.43 ± 0.02 pM (RSD ≤5.1%) after immunotherapy. Meanwhile, a high IFN-γ level of 0.67 ± 0.04 pM (RSD ≤6.2%) was detected in healthy controls. In addition, our study showed IFN-γ is a more effective biomarker for predicting patients' response to blockade therapy as compared to granzyme B.
Electrochemical sensor technology is an integral part of modern analytical chemistry that has att... more Electrochemical sensor technology is an integral part of modern analytical chemistry that has attracted great attention. It is multifaceted and rapidly progressing because of its high demand and continuous technological advancements. Electrochemical sensors offer several advantages over traditional analytical methods, including selectivity, sensitivity, robustness, ease of operation, short-time measurement, portability, low cost, etc. Interestingly, some of such features are possible to engineer toward a better performance improvement by adjusting to the assay needs. This review article comprehensively discusses the components, configuration, and tailoring of electrochemical sensors. The electrode surface modification and its importance in performance enhancement, especially in terms of selectivity and sensitivity, are discussed. The immobilization strategies, their advantages, and limitations, as well as the influential factors in surface engineering, are also highlighted. In addition, state-of-the-art electrochemical sensors either based on the immobilization matrices or recognition elements for a diverse range of target analytes are discussed. Challenges and future aspects are briefly reviewed. The author believes the insights presented here will spark extra efforts to further understand and in turn, develop electrochemical sensors.
Lung cancer is among the most life-threatening diseases, as it is by far the leading cause of dea... more Lung cancer is among the most life-threatening diseases, as it is by far the leading cause of death around the globe. However, plentiful studies have been reported with satisfactory results employing electrochemical biosensors, which make this method popular in lung cancer diagnosis. In assembling the sensing platforms, different materials of the sensor interfaces are utilized in electrode surface modification to enhance performance. A natural biopolymer chitosan (CS) is an outstanding material for the development of electrochemical biosensors. The unique physiochemical features exhibited by CS facilitate the preservation of its innovative traits and promote its secure adhesion onto the electrode surface. It also has inherent characteristics, such as high adsorption ability, good biocompatibility, eco-friendliness nature, greater heat stability, improved permeability, mechanical potency, outstanding layer-forming capability, and ease of availability. In combination with conductive materials, CS enables the modified electrodes to perform the best analytical results. This review is focused on the importance of CS in sensor configuration, advancements of CS-based electrochemical biosensors for detecting lung cancer biomarkers, and future prospects.
Rare earth elements are a set of seventeen metallic elements, which is an essential part of many ... more Rare earth elements are a set of seventeen metallic elements, which is an essential part of many high-tech devices. Hence, analysis and/or separation of the rare earth elements from their mineral become crucial. A novel analysis method combining ultraviolet-visible spectroscopic and multivariate analysis was developed to determine middle rare earth elements quickly and simultaneously. The data collected from ultraviolet-visible spectroscopic were analyzed by multivariate analysis. The results showed that the developed method has good accuracy and precision with a detection limit of 1.375 (± 0.012), 0.332 (± 0.004), 42.117 (± 0.200), 1.767 (± 0.011), and 0.576 (± 0.002) ppm, respectively for samarium, europium, gadolinium, terbium, and dysprosium. The interference effect of ammonium iron(II) sulfate hexahydrate, manganese(III) sulfate hydrate, calcium carbonate, sodium carbonate, and lead(II) nitrate were examined. The reliability of the proposed method was evaluated using monazite s...
According to regulation number 722/MENKES/Per/IX/88 of the Minister of Health of the Republic of ... more According to regulation number 722/MENKES/Per/IX/88 of the Minister of Health of the Republic of Indonesia, Rhodamine B is one of the dangerous dyes, and its use in food products is prohibited. Rhodamine B can cause adverse health effects including irritation, impaired liver function, and liver cancer. Although it has been banned, the use of Rhodamine B is still prevalent in the community's food supply, including shrimp paste. This can be observed in some of the shrimp pastes sold at the Ciroyom market in Bandung, which are bright red, uneven, and comprised of lumps. This study aims to determine the Rhodamine B content of shrimp paste sold at Ciroyom Market in Bandung, West Java, Indonesia. This research is descriptive in nature and employed a total sampling technique. Rhodamine B was analyzed in ten samples of commercially available red shrimp paste using a UV-Vis Spectrophotometer with a 565 nm wavelength. The results indicate that Rhodamine B was found in all samples, with co...
Granzyme B (GzmB) is a cytotoxic protease found in the granules of natural killer (NK) cells and ... more Granzyme B (GzmB) is a cytotoxic protease found in the granules of natural killer (NK) cells and cytotoxic T lymphocytes (CTLs), which participates in inducing apoptosis of target cells for NK cells and cytotoxic CD8+ lymphocytes [1]. GzmB is the major effector of the CTLs and NK cells in its killing attack on cancer cells, although the level of GzmB expression and its cytotoxic potential decrease significantly in the presence of cancer. This decrement is due to a ‘pro-cancer’ environment, where the cancer cells secrete soluble mediators that could inhibit and thus contribute to the decreased GzmB by CD8+ T cells and a reduction in their ability to cause apoptosis of the cancer cells. Once GzmB is secreted from cytotoxic cells, it can be discovered in two different host compartments, namely inside the target cell or extracellularly [2]. Due to this, the change of GzmB level in blood plasma may serve as indication of the patient’s cancer cure progress. Hence, we developed a disposabl...
A disposable amperometric biosensor with a dual monomers-based bioconjugate was developed for gra... more A disposable amperometric biosensor with a dual monomers-based bioconjugate was developed for granzyme B (GzmB) detection and for monitoring of the cancer progression of patients before and after immunotherapy. The biosensor was fabricated by immobilizing a GzmB monoclonal antibody (Ab1) on a poly3'-(2-aminopyrimidyl)-2,2':5',2''-terthiophene/gold nanoparticle (pPATT/AuNP) layer. The bioconjugate nanoparticles were synthesized through self-assembly of a monomer mixture of 2,2:5,2-terthiophene-3-(p-benzoic acid) (TBA) and PATT onto AuNPs, followed by chemical binding of brilliant cresyl blue (BCB) on TBA and GzmB polyclonal antibody (Ab2) on the PATT layer. Each sensing layer was investigated by surface analysis and electrochemical experiments. The sensor performance was assessed with selectivity, stability, reproducibility, detection limit, and real sample analysis. Under the optimized conditions, the dynamic range of GzmB was in two slopes from 3.0 to 50.0 pg/ml and from 50.0 to 1000.0 pg/ml with a detection limit of 1.75 ± 0.14 pg/ml (RSD ≤5.2%). GzmB monitoring was performed for the patient's serum samples, where a low level of GzmB was observed for lung cancer patients before immunotherapy (10.51 ± 0.99 pg/ml, RSD ≤6.2%), and the level was increased after therapy (17.19 ± 2.22 pg/ml, RSD ≤2.6%). Moreover, a significantly higher level was present in healthy persons (34.40 ± 3.92 pg/ml, RSD ≤1.4%). The cancer progression of patients before and after therapy was evaluated by monitoring GzmB levels in human serum using the proposed sensor.
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