Biochemical Detection System Research Articles

High versatility of polyethylene terephthalate (PET) waste for the development of batteries, biosensing and gas sensing devices

Continuously growing adoption of electronic devices in energy storage, human health and environmental monitoring systems increases demand for cost-effective, lightweight, comfortable, and highly efficient functional structures. In this regard, the recycling and reuse of polyethylene terephthalate (PET) waste in the aforementioned fields due to its excellent mechanical properties and chemical resistance is an effective solution to reduce plastic waste. Herein, we review recent advances in synthesis procedures and research studies on the integration of PET into energy storage (Li-ion batteries) and the detection of gaseous and biological species. The operating principles of such systems are described and the role of recycled PET for various types of architectures is discussed. Modifying the composition, crystallinity, surface porosity, and polar surface functional groups of PET are important factors for tuning its features as the active or substrate material in biological and gas sensors. The findings indicate that conceptually new pathways to the study are opened up for the effective application of recycled PET in the design of Li-ion batteries, as well as biochemical and catalytic detection systems. The current challenges in these fields are also presented with perspectives on the opportunities that may enable a circular economy in PET use.

Application of the fuzzy proportional integral differential (PID) temperature control algorithm in a liver function test system based on a centrifugal microfluidic device

Clinical laboratory examinations frequently include biochemical analysis of the liver. The presence of alanine aminotransferase (ALT) and aspartate transaminase (AST) in serum can be used to identify liver damage. In this study, a centrifugal microfluidic-based clinical biochemical detection system was developed for the detection of liver function markers. Using the centrifugal microfluidic chip and centrifugal force on the chip, separation of blood cells and serum was performed. The extraction and mixing of quantitative serum and diluent were completed under the chip design of microchannels and microchambers. The lyophilized reagent beads in the chip interacted with the combined solution. The Fuzzy PID algorithm regulates the power of the heating film to deliver the ideal reaction temperature. In accordance with Beer–Lambert, the rate of change in the absorbance of the reaction solution at 340 nm of the light source was measured and a standard curve for the relationship between concentration and rate of change in absorbance was constructed. The system is portable, quick, and simple to use because it uses a centrifugal microfluidic chip instead of the conventional detection and analysis approach. In the future, it is anticipated that the system will have several applications in the detection of highly integrated on-chip point-of-care devices.

Biochemical detection system for intermediates of endogenous antigen and elucidation of the role of molecular chaperones

Cytotoxic T lymphocytes recognize antigen-derived peptides (epitopes) bound to MHC class I presented on the cell surface of virus-infected cells and cancer cells. To date, numerous pathogen-derived epitopes and cancer cell-specific epitopes have been identified and used in the development of mRNA and peptide vaccines, but much remains unknown regarding the intracellular mechanisms that generate these antigen epitopes. These mechanisms are essential for cytotoxic T cell immunity. In this paper, I outline an innovation pioneered by Professor Nilabh Shastri and me, in which we developed a biochemical system to detect antigen intermediates and illuminated the role of molecular chaperones in antigen processing.

Performance verification of a biochemical detection system for hydrothorax and ascites and clinical diagnostic accuracy evaluation of exudate and tuberculous effusion.

Lactate dehydrogenase (LDH), total protein (TP) and glucose (Glu) in pleural hydrothorax and ascites can be used in the diagnosis of exudate, and adenosine deaminase (ADA) can be used in the diagnosis of tuberculous effusion. However, the manufacturers do not claim that their biochemical reagents can be used to detect hydrothorax and ascites samples. Therefore, medical laboratories must conduct suitability studies on biochemical reagents for hydrothorax and ascites samples to comply with regulatory requirements for humor detection. This study aimed to verify the analytical performance and clinical diagnostic accuracy of the Mindray biochemical reagents, including LDH, TP, Glu and ADA, for hydrothorax and ascites. The repeatability, detection limits and reference intervals of Mindray biochemical reagents (LDH, TP, Glu, ADA) in detecting hydrothorax and ascites were determined. The comparison of different measurement procedures was performed. Meanwhile, the diagnostic accuracy of LDH, TP, Glu and ADA were assessed. The quality control results of LDH, TP, Glu, and ADA were all under control. The repeatability coefficient of variation (%) of LDH, TP, Glu, and ADA were all less than 1%. The limits of blank of LDH, TP, Glu, and ADA were 0.33 U/L, 0.45 g/L, 0.00 mmol/L, and 0.04 U/L, respectively; the limits of detection were 1.57 U/L, 1.85 g/L, 0.05 mmol/L, and 0.12 U/L, respectively. Compared with the reference measurement program, the correlation coefficients of LDH, TP, Glu and ADA were 0.9931, 0.9983, 0.9996 and 0.9966, respectively; the regression equations were y=1.0082x-10.06, y=0.9965x-0.4732, y=0.9903x+0.0522 and y=1.0051x-0.0232, respectively. The reference intervals of LDH, TP, Glu, and ADA in hydrothorax and ascites were ≤198.39 U/L, ≤32.97 g/L, ≥5.03 mmol/L. and ≤11.00 U/L respectively. For differentiating between exudates and transudates, the area under the curve (AUC) of LDH, TP, and Glu were 0.913, 0.875, and 0.767, respectively; the AUC of ADA for the differential diagnosis of tuberculous and nontuberculous effusions was 0.876. The LDH, TP, Glu, and ADA assays were validated for use with the Mindray BS-2800 analyzer for hydrothorax and ascites evaluation. LDH, TP, and Glu in hydrothorax and ascites are applicable to the differential diagnosis of exudates and transudates; ADA in hydrothorax and ascites can be employed to differentiate and diagnose tuberculous and nontuberculous effusions.

Red ginseng extract improves skeletal muscle energy metabolism and mitochondrial function in chronic fatigue mice.

Background: Skeletal muscles are organs with high energy requirements, especially during vigorous exercise. Adequate mitochondrial function is essential to meet the high energy needs of skeletal muscle cells. Recent studies have reported that red ginseng can significantly improve chronic fatigue; however, the specific mechanism of action is still not clear. Methods: A chronic fatigue syndrome mouse model was developed using C57BL/6J mice through long-term compound stimulation of stress factors. Following this, the animals were orally administered 200, 400, or 600mg/kg red ginseng extracts for 28 days. Skeletal muscle lactate acid, serum lactate dehydrogenase, urea concentrations, ATP level, mitochondrial membrane potential, activities of Na+-K+-ATPase and cytochrome c oxidase were determined using assay kits or an automatic biochemical analyser detection system. Skeletal muscle mitochondria morphology was observed using electron microscopy and the expression of p-AMPK, PGC-1α, ACO2 and complex I in skeletal muscle protein was determined by western blotting. Results: Oral administration of 400 or 600mg/kg red ginseng extract in mice with chronic fatigue reduced lactic acid, lactate dehydrogenase and urea, rescued the density and morphology of skeletal muscle mitochondria, increased the activities of Na+-K+-ATPase and cytochrome c oxidase, and activated the AMPK/PGC-1α cascade pathway, resulting in improved skeletal muscle mitochondrial function by restoring ATP level, mitochondrial membrane potential, complex I and mitochondrial biogenesis. Conclusion: The anti-fatigue effects of red ginseng are partly related to its potent mitochondrial improving activity, including decreasing mitochondrial swelling and mitochondrial membrane permeability, increasing mitochondrial biogenesis, thus ameliorating mitochondrial dysfunction.

A Novel Detachable, Reusable, and Versatile Acoustic Tweezer Manipulation Platform for Biochemical Analysis and Detection Systems.

Multifunctional, integrated, and reusable operating platforms are highly sought after in biochemical analysis and detection systems. In this study, we demonstrated a novel detachable, reusable acoustic tweezer manipulation platform that is flexible and versatile. The free interchangeability of different detachable microchannel devices on the acoustic tweezer platform was achieved by adding a waveguide layer (glass) and a coupling layer (polydimethylsiloxane (PDMS) polymer film). We designed and demonstrated the detachable multifunctional acoustic tweezer platform with three cell manipulation capabilities. In Demo I, the detachable acoustic tweezer platform is demonstrated to have the capability for parallel processing and enrichment of the sample. In Demo II, the detachable acoustic tweezer platform with capability for precise cell alignment is demonstrated. In Demo III, it was demonstrated that the detachable acoustic tweezer platform has the capability for the separation and purification of cells. Through experiments, our acoustic tweezer platform has good acoustic retention ability, reusability, and stability. More capabilities can be expanded in the future. It provides a simple, economical, and multifunctional reusable operating platform solution for biochemical analysis and detection systems.

An automatic whole blood analyzer for renal function analysis with a centrifugal microfluidic device.

In recent years, chronic kidney disease (CKD) has received widespread attention as one of the fastest growing non-communicable diseases (NCD) worldwide. Here, a clinical biochemical detection system based on a centrifugal microfluidic chip was designed to simplify the rapid detection of renal function indices. A photosensor was used to design an optical signal acquisition structure that can detect products or substrates after enzymatic reactions of uric acid, creatinine, and urea. The weak optical signals collected from this structure were processed using a pre-designed amplifying circuit and a software algorithm to calculate absorbance. The relationship between absorbance and concentration was established according to the Beer-Lambert law. The results indicated good stability and accuracy of the system, which is 21.3 cm × 16.5 cm × 19 cm in size as compared to other detection systems due to the adoption of a centrifugal microfluidic chip. It was portable and easy to operate, in addition to its ability to rapidly detect renal function indices. This system exhibits great potential for the detection of highly integrated point-of-care testing in the future.

A photocathode based on BiOI-Bi/CNTs for microRNA detection coupling with target recycling strand displacement amplification

A novel cathode photoelectrochemical (CPEC) biosensor by integrating BiOI-Bi/CNTs photocathode with target recycling strand displacement amplification (TRSDA) was proposed for selective and sensitive detection of microRNA (miRNA). Herein, an innovative strategy of two-site hybridization in a hairpin loop to specifically recognize the target miRNA was designed. Strand displacement amplification (SDA) reaction was triggered by target let-7a miRNA with the assistance of polymerase and nicking enzyme. TRSDA was then realized by using short complementary sequence hidden in the 3′-terminal region of the hairpin probe stem, which produced large amount of product DNA (pDNA). The as-generated pDNA fragments were collected by capture probe (CP) on BiOI-Bi/CNTs platform. Since K3[Fe(CN)6] could take in photoelectrons from BiOI-Bi/CNTs effectively, the photocurrent was largely decreased because DNA layer on CPEC platform inhibited photoelectron transfer towards electron acceptor. Under optimized conditions, the photocurrent response of biosensor was linear with let-7a concentration from 0.2 to 2000 pM, and the detection limit (S/N = 3) was as low as 0.1 pM. The proposed approach opened up new opportunity for developing robust biochemical detection systems.

Development and application of urine biochemical detection system for a disc microfluidic chip

The predecessor of China Optics was China Optics and Applied Optics Digest, which was founded in 1985. At that time, it was the only retrieval journal in the field of optics in China. At the end of 2008, China Optics and Applied Optics Digest was renamed

3D-Printed Pneumatic Microfluidic Mixer for Colorimetric Detection of Listeria monocytogenes

Abstract. 3D printing can significantly improve the current fabrication techniques for microfluidic devices due to its ability to create truly 3D structures in a single step. In this study, an active pneumatic microfluidic mixer was designed and fabricated using an extrusion-based 3D printer and used for rapid detection of . The printed material of the mixer is flexible, semi-transparent, and inexpensive. The fabrication time is significantly shorter than the traditional micromolding process. The printed mixer consists of two pneumatic air chambers and one mixing chamber designed for a fluidic sample size of 100 µL. The length, width, and height of the mixer chip are 13, 12.7, and 9 mm, respectively. The performance of the mixer was tested for different actuation frequencies and pneumatic pressures. The completed 3D-printed mixer was successfully applied to the colorimetric detection of for a concentration range from 102 to 108 cfu mL-1 using an enzyme-linked immunosorbent assay. The experimental results showed that the microfluidic mixer could enhance the mixing efficiency of the fluidic sample through pneumatically actuated diaphragms. In addition, the mixer could accelerate the color development caused by target , and the observed color changes could be discriminated within 5 min by naked eye. The present work will contribute to the development and optimization of a prototype for rapid detection of in food samples. It provides an effective technical approach to realize the fabrication of low-cost microfluidic chips for efficient reagent mixing in microscale biochemical detection systems. Keywords: 3D printing, Listeria monocytogenes, Microfluidic mixer, Rapid detection.

Toward Label-Free Biosensing With Silicon Carbide: A Review

Recent innovation in microelectrical–mechanical systems (MEMSs) and plasmonics-based technologies has opened up perspectives for label-free sensing of biological and chemical analytes. Label-free sensing would enable increased sensitivity and miniaturization capabilities for biosensing devices. Silicon carbide is a semiconductor material that happens to possess ideal properties for augmenting both the MEMS/nanoelectromechanical systems and the plasmonics routes. It has remarkable chemical and biological inertness resulting in a high degree of biocompatibility, as well as pronounced mechanical resilience. In addition, it is an efficient (low loss) plasmonic metamaterial. Its cubic polytype can be grown on silicon wafers, allowing easy micromachining into building blocks for sensing devices, scalable to large volume production. Finally, silicon carbide is an ideal starting material for a controlled, wafer-scale growth of graphene, offering an additional wealth of excellent properties for nanosensing. The combination of all of these capabilities makes silicon carbide an outstanding material platform for the realization of label-free, analyte-specific, and highly sensitive biochemical molecule detection systems. These technologies will open exciting horizons in terms of high throughput, efficient drug screening, and early pathogen detection.

On-Line HPLC with Biochemical Detection for Screening Bioactive Compounds in Complex Matrixes

On-line high-performance liquid chromatography (HPLC) coupled with biochemical detection (BCD) has been developed to screen compounds showing antioxidant action, enzyme inhibition and receptor affinity in complex matrixes. This review summarizes HPLC methods combining different post-column detection methods, such as diode-array detection (DAD), mass spectrometry (MS), chemiluminescence (CL) and nuclear magnetic resonance, for antioxidant screening. The methods based on a single relatively stable reagent such as DPPH• and ABTS•+ were the most popular. Oxygen free radical scavengers mainly depended on post-column CL detection. The on-line hyphenated HPLC–BCD systems based on post-column UV/DAD fluorescence and MS detection were also widely applied to screen enzyme- and receptor-active compounds. These strategies provide a convenient tool for quick identification and quantification of active compounds in complex matrixes.

Simultaneous separation, identification and activity evaluation of three butyrylcholinesterase inhibitors from Plumula nelumbinis using on-line HPLC-UV coupled with ESI-IT-TOF-MS and BChE biochemical detection

We have firstly established a method of high-performance liquid chromatography−ultraviolet analysis coupled with electrospray ionization−ion trap−time-of-flight mass spectrometry and butyrylcholinesterase biochemical detection (HPLC-UV-ESI-IT-TOF-MS-BChEBCD). Applying this on-line method to the identification of BChE inhibitors in a Plumula nelumbinis sample, three alkaloids, namely liensinine, isoliensinine, and neferine, have been detected as having a strong BChE inhibition activity for the first time; in addition, norisoliensinine and 6-hydroxynorisoliensinine were proposed as two new compounds identified by their UV and MS data. The HPLC fingerprint, the MS fragments of the components, and the BChE activity profile could be simultaneously recorded during real-time analysis of complex samples using this on-line approach. Tacrine, a BChE inhibitor, was used as a positive reference compound, and its detection limit in the biochemical detection system was 1nmol. The BChE activity of 1g of P. nelumbinis sample was equal to that of 127.88μmol tacrine. The proposed on-line method has been validated as having good precision and reproducibility, and could be used to rapidly identify BChE inhibitors and to screen potential drugs for the treatment of Alzheimer's disease in complicated samples.

In vivo investigation of the substrate recognition capability and activity affecting amino acid residues of glycosyltransferase FscMI in the biosynthesis of candicidin

Alteration of sugar moieties of natural products often leads to novel antibiotics with different chemical and physical properties. fscMI is a putative glycosyltransferase (GT) in a gene cluster for the production of candicidin, a polyene macrolide antibiotic, produced by Streptomyces sp. FR-008. In this report, we established an in vivo biochemical detection system by inactivating fscMI and the DH11 domain of polyketide synthase (PKS) through double homologous recombination to unveil the interaction between polyene GTs and their substrates. We found that homologous GT genes including amphDI, nysDI and pimK can catalyze the conversion of candicidin aglycone into candicidin/FR-008-III in fscMI mutant, suggesting that homologous polyene GTs show some tolerance toward aglycones and that it is possible to create new polyene analogues with altered aglycones through genetic engineering. Inactivation of the DH11 domain of PKS led to novel polyene derivatives with mycosamine added to the altered polyketide backbones, further confirming the loose substrate specificity of polyene GTs. Furthermore, mutation of Ser346, Ser361, His362 or Cys387 of FscMI by site-directed mutagenesis significantly reduced its catalytic activity. Further analysis suggested that Ser361 and Cys387 are likely the critical donor interacting residues that could affect the activity of GT FscMI. To our knowledge, this is the first report of the critical residues in a polyene GT.

Decrease in RNA Folding Cooperativity by Deliberate Population of Intermediates in RNA G‐Quadruplexes

Keeping a broad (RNA) perspective: conventional biochemical detection systems only have a 100-fold linear response range. The range of potassium concentrations detected by an RNA G-quadruplex sequence can be broadened by intentionally populating multiple intermediate folding states. The folding of the RNA G-quadruplexes was monitored by both circular dichroism and intrinsic fluorescence spectroscopy.

Development of On-line Liquid Chromatography-Biochemical Detection for Soluble Epoxide Hydrolase Inhibitors in Mixtures

In this study, an end-point-based fluorescence assay for soluble epoxide hydrolase (sEH) was transformed into an on-line continuous-flow format. The on-line biochemical detection system (BCD) was coupled on-line to liquid chromatography (LC) to allow mixture analysis. The on-line BCD was based on a flow system wherein sEH activity was detected by competition of analytes with the substrate hydrolysis. The reaction product was measured by fluorescence detection. In parallel to the BCD data, UV and MS data were obtained through post-column splitting of the LC effluent. The buffer system and reagent concentrations were optimized resulting in a stable on-line BCD with a good assay window and good sensitivity (S/N > 60). The potency of known sEH inhibitors (sEHis) obtained by LC-BCD correlates well with published values. The LC-BCD system was applied to test how oxidative microsomal metabolism affects the potency of three sEHis. After incubation with pig liver microsomes, several metabolites of sEHis were characterized by MS, while their individual potencies were measured by BCD. For all compounds tested, active metabolites were observed. The developed method allows for the first time the detection of sEHis in mixtures providing new opportunities in the development of drug candidates.

A biochemical system of rapidly detecting bacteria based on ATP bioluminescence technology

A biochemical detection system based on ATP bioluminescence which can detect bacteria and microorganisms automatically and rapidly is proposed. Meanwhile, reagent formulations are optimized. In the detecting system, weak fluorescence loss is calibrated, and receiving efficiency of the photomultiplier tube is improved by making use of optical unit. The results show that rapid detection accuracy can reach 86 % compared with the traditional plate-counting method, the detecting time is controlled within twenty minutes, and detectable ATP concentration range achieves 10−15–10−8 M. Moreover, the series of curves obtained by measurements for the common variety of food (drinks, meat etc.) show that the device has a good performance and gets satisfactory testing results.

Performance verification of the 7600 biochemical analyzer detection system

Objective To verify the main analyzing performance of the 7600 automatic biochemical analyzer，production of Hitachi Corporation of Japan.Methods Following the method how EP5­A，EP6­A were tested as described in the instruction of the National Committee for Clinical Laboratory Standards (NCCLS)，precision，linearity and reportable range of the selected biochemical testing items were evaluated.Results All the within­run precision of Hitachi 7600 testing items were within the required 1/4 CLIA ′88 but Na，all the between­run precision were within the required 1/3 CLIA ′88 but Na；the linear verification results got the regression equation of the theoretical and measured values y＝bx＋a，in which b was within the range of 0.97­1.03，a was within an acceptable range；the reportable range verification results showed that after the samples being diluted by different proportions，the theoretical/measured values were all between 90% and 110%，indicating that within a certain range of sample dilution the test results were reliable.Conclusions Precision，linearity and reportable range of the detection system met the basic requirements of the experiments in clinical diagnosis and the method detecting Na should be improved.

Raman spectroscopy in head and neck cancer

In recent years there has been much interest in the use of optical diagnostics in cancer detection. Early diagnosis of cancer affords early intervention and greatest chance of cure. Raman spectroscopy is based on the interaction of photons with the target material producing a highly detailed biochemical 'fingerprint' of the sample. It can be appreciated that such a sensitive biochemical detection system could confer diagnostic benefit in a clinical setting. Raman has been used successfully in key health areas such as cardiovascular diseases, and dental care but there is a paucity of literature on Raman spectroscopy in Head and Neck cancer. Following the introduction of health care targets for cancer, and with an ever-aging population the need for rapid cancer detection has never been greater. Raman spectroscopy could confer great patient benefit with early, rapid and accurate diagnosis. This technique is almost labour free without the need for sample preparation. It could reduce the need for whole pathological specimen examination, in theatre it could help to determine margin status, and finally peripheral blood diagnosis may be an achievable target.

Development of a Countergradient Parking System for Gradient Liquid Chromatography with Online Biochemical Detection of Serine Protease Inhibitors

A gradient HPLC approach in combination with a countergradient system for online biochemical detection (BCD) to screen for inhibitors of serine proteases is described. For gradient separations, this novel countergradient system was developed to produce a biocompatible constant solvent composition in the BCD. The countergradient system is based on retaining complete gradients in an additional preparative HPLC column, followed by subsequent and reversible elution to the separation column effluent. Major advantages compared with existing countergradient systems are that no additional LC pumps are needed and enhanced stability. The developed countergradient system was systematically characterized applying different gradient programs. Inhibitors eluting in a postcolumn continuous flow analysis interfere with the enzymatic release of fluorescent 7-amino-4-methylcoumarin (AMC) from an AMC-labeled peptide. The inhibitory activity of eluting substances is sensitively detected as the degree of reduced fluorescence intensity. This biochemical detection system (BCD) for proteases was validated with three known inhibitors of the benzamidine type. Their IC 50 values were in good accordance with the results of conventional plate reader assays. Finally, a small library of protease inhibitors was successfully screened with the combination of the BCD and the countergradient system.