Fetal Bovine Serum Research Articles

Automated Manufacturing Processes and Platforms for Large-scale Production of Clinical-grade Mesenchymal Stem/ Stromal Cells.

Mesenchymal stem/stromal cells (MSCs) hold immense potential for regenerative medicine due to their remarkable regenerative and immunomodulatory properties. However, their therapeutic application requires large-scale production under stringent regulatory standards and Good Manufacturing Practice (GMP) guidelines, presenting significant challenges. This review comprehensively evaluates automated manufacturing processes and platforms for the scalable production of clinical-grade MSCs. Various large-scale culture vessels, including multilayer flasks and bioreactors, are analyzed for their efficacy in MSCs expansion. Furthermore, automated MSCs production platforms, such as Quantum® Cell Expansion System, CliniMACS Prodigy®, NANT001/ XL, CellQualia™, Cocoon® Platform, and Xuri™ Cell Expansion System W25 are reviewed and compared as well. We also underscore the importance of optimizing culture media specifically emphasizing the shift from fetal bovine serum to humanized or serum-free alternatives to meet GMP standards. Moreover, advances in alternative cryopreservation methods and controlled-rate freezing systems, that offer promising improvements in MSCs preservation, are discussed as well. In conclusion, advancing automated manufacturing processes and platforms is essential for realizing the full potential of MSCs-based regenerative medicine and accomplishing the increasing demand for cell-based therapies. Collaborative initiatives involving industry, academia, and regulatory bodies are emphasized to accelerate the translation of MSCs-based therapies into clinical practice.

Virus susceptibility of a new cell line derived from the muscle of koi (Cyprinus carpio koi).

In this study, a continuous cell line (KM cells) derived from koi (Cyprinus carpio koi) muscle was established and characterized. The KM cells were subcultured for more than 70 passages and showed high viability after long-term cryopreservation. The KM cell line was optimally cultured in medium 199 containing 10% foetal bovine serum at 25°C. A chromosome analysis indicated that the cell line remained diploid, with a mean chromosome count of 100. DNA sequencing and comparative analysis of the 16S rRNA and cytochrome oxidase I gene sequences showed that the KM cell line originated from koi. In transfection experiments using the plasmid pEGFP, KM cells demonstrated a high level of transfection efficiency, suggesting their potential for use in foreign gene expression studies. Inoculation with spring viraemia of carp virus (SVCV) resulted in a substantial cytopathic effect, and the level of production of SVCV in KM cells was higher than that in the epithelioma papulosum cyprinid (EPC) cell line that is normally used to produce the virus. However, no cytopathic effect was observed when these cells were inoculated with koi herpesvirus, carp oedema virus, or grass carp reovirus. These observations suggest that the newly established KM cell line will be a valuable tool for investigating the pathogenesis of infection with spring viraemia of carp virus.

Translational implications of a novel combination of iPRF and collagen scaffold for proliferation of gingival mesenchymal stem cells.

"Tissue engineering," is a concept that involves the use of scaffolds, cells, and growth factors/signaling molecules in the field of regenerative medicine. The present study was carried out to evaluate the attachment and depth of penetration of the Gingival Mesenchymal Stem Cells (GMSCs) onto the collagen scaffold preconditioned with Fetal Bovine Serum (FBS), Injectable Platelet Rich Fibrin (i-PRF) and a combination of FBS with i-PRF using histological analysis and environmental scanning electron microscopy (ESEM) respectively. In the present study, commercially available collagen membranes were used as scaffolds and divided into 3 groups where Group I was preconditioned with FBS, Group II was preconditioned with i-PRF, and Group III with a combination of FBS and i-PRF. Scaffolds were then seeded with GMSCs and incubated in a CO2 incubator at 37 0C for 7 days. Both histological and ESEM analysis showed proliferation, attachment, and depth of penetration along with the combination of cell morphological changes in all the three groups. In group I cells showed mild depth of penetration along with a round morphological appearance. In group II the cells showed moderate depth of penetration and rounded morphology. In group III maximum depth of penetration was seen along with the round and spheroidal morphology of cells. The combination of the growth media showed the best effect on cell attachment, depth of penetration, and cell morphology. This is the first report demonstrating the effect of the combination of collagen and i-PRF supports the proliferation of GMSCs. Since FBS alone and i-PRF alone exhibited similar cell proliferation it is recommended that i-PRF could be used in clinical scenarios making it xenofree.

Lysate of bovine adipose-derived stem cells accelerates in-vitro development and increases cryotolerance through reduced content of lipid in the in vitro fertilized embryos

Mesenchymal stem cells such as adipose-derived stem cells (ADSCs) are known to secrete factors that stimulate cell division and promote regeneration in neighboring cells. While conditioned medium from stem cells has been used in blastocyst production, no studies have examined the use of cell lysates. In this study we investigated the effects of adding ADSC lysate to in vitro culture (IVC) medium. ADSCs and fibroblasts were isolated from bovine adipose tissue and auricular tissue, respectively, and their lysates were prepared by freeze-thaw disruption. ADSC lysate was added to synthetic oviductal fluid medium. The effects on cleavage, blastocyst development rates, cell numbers, cryotolerance, gene expression (POU5F1, BAX, IGF1R, IGF2R, SOD2), lipid content, and membrane integrity were evaluated according to the experimental design. In Expt. 1, the comparison involved adding ADSC or fibroblast lysate alongside the control group. The total blastocyst rate increased when ADSC lysate was introduced (ADSCs: 40.1%, fibroblasts: 33.1%, control: 27.3%). However, there were no significant differences in the number of trophoblast cells or in the inner cell mass. Experiment 2 confirmed that this increase in blastocyst development was not due to the solvent, PBS(-). In Expt. 3, addition of 10% fetal calf serum (FCS) or ADSC lysate increased the total blastocyst rate compared to the control (control, 26.2%; 10% FCS, 43.4%; 1% ADSC lysate, 34.2%; 10% ADSC lysate, 48.1%). After freezing and thawing, the survival and hatching rates of embryos with FCS were significantly lower than those of the control as well as those with added ADSC lysate. In Expt. 4, the addition of ADSC lysate or FCS had no significant effect on gene expression in blastocysts compared to control. However, the addition of FCS significantly increased the gray intensity, indicating higher lipid content compared to the control, with a significant increase in the number of dead cells in the blastocyst. These results indicate that the addition of ADSC lysate to the IVC medium accelerates bovine blastocyst development and that its 10% addition, corresponding to 1 x 105 cells/mL, is as effective as 10% FCS without a decrease in cryotolerance due to the increased lipid content.

Evaluation of chelating agents based on pyridine-azacrown compounds H4PATA, PATAM, and H4PATPA for 68Ga and 177Lu

In this article, we present the synthesis and characterization of three macrocyclic chelators, H4PATA, PATAM, and H4PATPA, based on a pyridine-azacrown compound. Their complexation with 68Ga and 177Lu has been thoroughly investigated using MALDI TOF MS, 1H NMR spectroscopy, radiolabeling studies, and experiments in vitro with fetal bovine serum and a 1000-fold molar excess of H4EDTA. Our studies have shown that the chelators H4PATA and H4PATPA form complexes at room temperature with both radionuclides (RCY >80 % and >90 % for complexes with H4PATA and H4PATPA after 30 min, respectively). The chelator PATAM requires high temperatures (95 °C) for complexation. In vitro stability assays in fetal bovine serum as well as H4EDTA-challenge revealed that transchelation occurs for all complexes with 68Ga. However, complexes of the ligands H4PATA and PATAM with 177Lu were found stable. Thus, taking into account the radiolabeling at room temperature and in vitro stability of the complex [177Lu]Lu·PATA, our investigations revealed the chelator H4PATA is a candidate for radiopharmaceutical use with 177Lu.

Enhanced Stability of Hairpin-Functionalized DNA Tetrahedral Nanostructures for miRNA Detection in Plasma from Ischemic Stroke Patients

The enzyme-free amplification technique using the Hybridization Chain Reaction (HCR) is gaining traction for its efficiency in miRNA analysis. Conventional HCR (C-HCR) with hairpin probes faces challenges due to enzymatic degradation in body fluids, leading to potential false-positive results. This study addresses the critical need for a more reliable method that resists enzymatic breakdown and improves diagnostic accuracy for detecting miRNA related to ischemic stroke. We have developed a novel DNA tetrahedral nanostructures-mediated HCR (DTN-HCR) platform for the precise detection of microRNA-25 (miR-25), a biomarker for ischemic stroke. Incorporating two unique DNA tetrahedral nanostructures with embedded hairpin structures (DTN-HP1 and DTN-HP2), this platform activates upon miR-25 binding, initiating a robust DTN-HCR reaction. This reaction forms extensive DNA tetrahedron clusters that significantly boost the fluorescence signal, enabling detection thresholds as low as 5.4 pM. The method showcases exceptional specificity by distinguishing target miRNA from close analogues and maintains structural integrity against DNase I and fetal bovine serum (FBS), verified through polyacrylamide gel electrophoresis (PAGE). It successfully differentiates ischemic stroke patients from healthy controls by analyzing peripheral blood-derived miRNAs. This study concludes that the DTN-HCR platform substantially enhances the specificity and stability of miRNA detection, marking a significant advancement in non-enzymatic miRNA analysis techniques. With its capability to accurately identify ischemic stroke biomarkers at very low concentrations and its resistance to enzymatic degradation, the DTN-HCR method presents a valuable diagnostic tool for ischemic stroke, potentially improving early detection and monitoring in a clinical environment.

Beyond a ferroptosis inducer: erastin can suppress nutrient deprivation induced cell death in the intervertebral disc

Background: Erastin has been found to induce ferroptosis; however, whether erastin may have roles other than ferroptosis inducer in cells is unknown. Nutrient deficiency is one of the major causes of many diseases including intervertebral disc (IVD) degeneration. Purpose: The current study investigates the effect of erastin in nucleus pulposus cells under nutrient deprivation condition. Study Design: Experiment in vitro and ex vivo. Methods: The effect of erastin on the cell survival of nucleus pulposus cells was evaluated in fetal bovine serum (FBS) and glucose deprivation condition. RSL3 and ferrostatin-1 were applied to illustrate whether the effect of erastin is ferroptosis dependent. The involvement of solute carrier family 7, membrane 11(SLC7A11), autophagy as well as mechanistic target of rapamycin kinase complex 1(mTORC1) and transcription factor EB (TFEB) were assessed to demonstrate the working mechanism of erastin. Results: Erastin may induce cell death at the concentration of ≥ 5μM; however, it may protect nucleus pulposus cells against nutrient deprivation induced cell death at lower concentration (0.25-1μM) and the effect of erastin is ferroptosis independent. The mechanism study showed that the effect of erastin may relate to its SCL7A11 regulation, as SCL7A11 knock-down may have the similar effect as erastin. Furthermore, it was also demonstrated that mTORC1-TFEB mediated autophagy was involved in protective effect of erastin. Conclusions: Low dose erastin may promote cell survival under nutrient deprivation condition, and its effect is ferroptosis independent; erastin may exert its protective effect through mTORC1-TFEB mediated autophagy regulation. Clinical Significance: Nutrient deprivation is a major contributor to intervertebral disc degeneration. Our in vitro and ex vivo study showed that low dose of erastin may suppress nutrient deprivation induced cell death in IVD degeneration. Although it was not validated in vivo model due to lack of in vivo nutrient deprivation induced IVD degeneration model currently, this study may still provide a potential therapeutic option for IVD degeneration, which of cause need further validation.

Mouse liver blood flow is regulated by hepatic stellate cells in response to the sympathetic neurotransmitter norepinephrine

BackgroundThere is no clear information on the regulation of liver blood flow by the autonomic nervous system. We conducted this study to investigate whether quiescent hepatic stellate cells (qHSCs) regulate liver blood flow in response to the sympathetic neurotransmitter norepinephrine (NE). MethodsqHSCs isolated from mice were cultured in Dulbecco's modified Eagle medium without fetal bovine serum for 1 day on collagen gel. NE-induced qHSC contraction was evaluated using the quantitative single-cell contraction measurement method that we had developed previously. For the measurement of liver perfusion pressure in situ, a buffer solution was perfused from the portal vein in mice. ResultsNE-induced a reversible contraction of qHSCs. This contraction was suppressed by the nonmuscle myosin II inhibitor blebbistatin, the myosin light chain kinase inhibitor ML-9, the Rho kinase inhibitor H-1152, the calmodulin inhibitor W-7, the store-operated calcium channel inhibitor YM-58483, and the IP3 receptor inhibitor xestospongin C. In contrast, the transient receptor potential C channel inhibitor SKF96365 did not affect the NE-induced contraction. ConclusionThese results suggest that qHSCs contract in response to NE. New & noteworthyThe present study provides direct evidence for the first time that norepinephrine (NE) induces a reversible contraction of isolated single quiescent hepatic stellate cells (qHSCs) and further suggests that the NE-mediated qHSC contraction participates in the regulation of liver blood flow in vivo.

Design of Experiments to Tailor the Potential of BSA-Coated Peptide Nanocomplexes for Temozolomide/p53 Gene Co-Delivery

Background: Gene therapy can be viewed as a promising/valuable therapeutic approach directed to cancer treatment, including glioblastoma. Concretely, the combination of gene therapy with chemotherapy could increase its therapeutic index due to a synergistic effect. In this context, bovine serum albumin (BSA)-coated temozolomide (TMZ)-peptide (WRAP5)/p53 gene-based plasmid DNA complexes were developed to promote payload co-delivery. Methods: Design of experiments (DoE) was employed to unravel the BSA-coated TMZ-WRAP5/p53 nanocomplexes with the highest potential by considering the nitrogen to phosphate groups ratio (N/P), and the BSA concentration as inputs and the size, polydispersity index, surface charge and p53-based plasmid complexation capacity (CC) as DoE outputs. Results: The obtained quadratic models were statistically significant (p-value < 0.05) with an adequate coefficient of determination, and the correspondent optimal points were successfully validated. The optimal complex formulation had N/P of 1.03, a BSA concentration of 0.08%, a size of approximately 182 nm, a zeta potential of +9.8 mV, and a pDNA CC of 96.5%. The optimal nanocomplexes are approximately spherical. A cytotoxicity assay showed that these BSA-coated TMZ-WRAP5/p53 complexes did not elicit toxicity in normal brain cells, and a hemolysis study demonstrated the hemocompatibility of the complexes. The complexes were stable in cell culture medium and fetal bovine serum and assured pDNA protection and release. Moreover, the optimal BSA-coated complexes were able of gene transcription and promoted a significant inhibition of glioblastoma cell viability. Conclusions: The reported findings instigate the development of future research to evaluate their potential utility to TMZ/p53 co-delivery. The DoE tool proved to be a powerful approach to explore and tailor the composition of BSA-coated TMZ-WRAP5/p53 complexes, which are expected to contribute to the progress toward a more efficient therapy against cancer and, more specifically, against glioblastoma.

Reducing the danger of phytopathogen toxins by using an organomineral composition

Relevance. Contamination by toxins of phytopathogens or mycotoxins of food and feed raw materials of plant origin poses a serious threat to the production of high-quality and safe agricultural products. Reducing the risks of contamination of plant raw materials with mycotoxins depends on the effective use of biological products to reduce the toxicity of mycotoxins.Methods. Experiments were carried out on primary rat liver cells. Primary liver cells were cultured in DMEM medium in the presence of 10% fetal calf serum at 37OC and 5% CO2. Zearalenone and T-2 toxin were dissolved in a mixture of DMSO and 96% alcohol in a ratio 1:1. Zearalenone T-2 toxin and protective compositions were mixed and aged together for 6 hours and after exposure added to a medium with a cellular monolayer. The concentration of bacterial-based compositions KMBI-3 and KMCI-3 was used for research in three variants: 0.4 mg/ml, 2 mg/ml, 4 mg/ml. After 24 hours of cultivation, the cell layer was evaluated using an inverted microscope according to the following parameters: percentage of surface coverage, cell shape, number of cell aggregates, number of floating cells.Results. A dose-dependent decrease in cell viability was revealed when exposed to zearalenone and T-2 toxin, the most toxic effect was observed at doses from 0.5 х 10-4 and 8.6 х 10-8 M and 2.14 х 10-7 M, respectively. When using the protective composition KMBI-3 at a dose of 4 mg/ml, the least negative effect of zearalenone and T-2 toxin on cell culture was observed. The use of compositions of organomineral origin KMBI-3 helps to increase cell viability when exposed to the toxins zearalenone and T-2 toxin, which indicates the activation of proliferative processes in comparison with the group without the use of drugs. The use of the biopreparation KMBI-3 reduces the pathogenic effect of zearalenone and T-2 toxin on cell culture, increases the resistance of liver cells to the effects of phytopathogen toxins.

Regulation of hepatic transporters OATP1A2 and OATP1B1 by the action of nitric oxide (II)

Nitric oxide II (NO) is a signaling molecule that has a wide range of physiological effects, including the regulation of gastrointestinal processes. The liver actively expresses the clinically significant transporters OATP1A2 and OATP1B1, which are involved in the influx of biologically active and medicinal substances. That is why it seems relevant to determine the pathways of regulation of hepatic transporters under the influence of NO. Aim. To study the effect of NO on the relative amount and expression of the transporters OATP1A2 and OATP1B1 in vitro in HepG2 cells. Materials and methods. The study was performed on a culture of HepG2 cells, which were cultured in 6-well plates at 37 °C and 5% CO2 in Dulbecco’s modified Eagle’s medium (DMEM) with a high glucose content (4500 mg/l) containing L-glutamine (4 mM), 10% fetal bovine serum, 100 U/ml penicillin and 100 mg/ml streptomycin (all components from Sigma-Aldrich, Germany). S-nitrosoglutathione (Sigma-Aldrich, Germany) was added to the culture medium at concentrations of 1, 10, 50, 100 and 500 µM, incubated for 24 and 72 hours. Water for injection (solvent) was added to control cells in an equivalent volume S-nitrosoglutathione). The relative amounts of OATP1A2 and OATP1B1 proteins were assessed by Western blot, and the expression of SLCO1A2 and SLCO1B1 by real-time PCR. The results of the study. In the course of this study, it was shown that the addition of S-nitrosoglutathione in the concentration range of 10-500 μM and exposure duration of 24 and 72 hours causes an increase in the intracellular level of nitric oxide metabolites, which indicates the adequacy of the use of this NO donor. At the same time, under the influence of NO, there was an increase in the relative amount of the studied transporters - OATP1A2 at an exposure period of 24 hours and S-nitrosoglutathione concentrations of 50 and 100 μM, OATP1B1-24 and 72 hours, at concentrations of 10-500 μM, a similar trend was noted for the expression genes SLCO1A2 and SLCO1B1. Conclusion. The NO donor - S-nitrosoglutathione causes an increase in the relative amount of OATP family transporters - OATP1A2 and OATP1B1, due to increased expression of the SLCO1A2 and SLCO1B1 genes, in vitro in HepG2 cells.

Carbon cloth surface engineering for simultaneous detection of ascorbic acid, dopamine, and uric acid in fetal bovine serum

Carbon cloth (CC) was electrochemically activated using three electrochemical methods in different electrolytes. The gases released during the activation process etched the surface of the CC, thereby increasing its surface area of the activated CC (FCC). Moreover, functional groups such as oxygen-containing groups and N-doping have been introduced. The quantity and type of functional groups introduced during the activation process were related to the anions in the solution. FCC electrodes were used to construct electrochemical sensors for the simultaneous determination of ascorbic acid (AA), dopamine (DA), and uric acid (UA). The PFCC electrode activated by advanced cyclic voltammetry in (NH4)2HPO4 showed linear ranges for AA, DA, and UA concentrations of 0.1 to 2.1 mM, 0.5 to 11 µM, and 0.5 to 11 µM, respectively. The detection limits are 72.93, 0.22, and 0.42 µM, respectively. The good flexibility the PFCC electrode made it suitable for the preparation of flexible sensors. The simultaneous determination of AA, DA, and UA in fetal bovine serum showed a reliable recovery ratio. This study provides a simple and green approach for activating carbon cloth and constructing flexible electrochemical sensors with the potential to simultaneously detect AA, DA, and UA.

The Biological Effect of Enriching the Plasma Content in Platelet-Rich Plasma: An In Vitro Study.

Platelet-rich plasma (PRP) formulations have become valuable therapeutic tools in regenerative medicine. In addition, these blood derivates have been successfully included in cell therapy as fetal bovine serum substitutes, due to the real need to avoid the risk of host immunologic reactions and the animal disease transmission associated with reagents from animal origin. However, the protocols for obtaining them should be optimized to improve their biological potential. PRP-derived preparations with different concentrations of the platelet and plasma components were obtained from the blood of five donors by freeze-drying. Measurements of the pH, protein, and growth factor concentration were performed. Moreover, their biological effects on cell proliferation and migration and their angiogenic potential were assessed. An increased plasma component concentration resulted in an augmented quantity of the total protein content, a significative variation in the hepatocyte growth factor concentration, and an experimental but clinically irrelevant alteration of the pH value. No significant changes were induced in their potential to enhance proliferative and migratory responses in epithelial cells, with the latter being reduced for dermal fibroblasts. The endothelial cell capacity for tube formation was significatively reduced. An increased blood plasma content did not improve the biological potential of the formulations. However, they have emerged as a promising approach for regenerative therapies where neovascularization must be avoided.

Enhanced Electrochemiluminescence of Luminol and-Dissolved Oxygen by Nanochannel-Confined Au Nanomaterials for Sensitive Immunoassay of Carcinoembryonic Antigen.

Simple development of an electrochemiluminescence (ECL) immunosensor for convenient detection of tumor biomarker is of great significance for early cancer diagnosis, treatment evaluation, and improving patient survival rates and quality of life. In this work, an immunosensor is demonstrated based on an enhanced ECL signal boosted by nanochannel-confined Au nanomaterial, which enables sensitive detection of the tumor biomarker-carcinoembryonic antigen (CEA). Vertically-ordered mesoporous silica film (VMSF) with a nanochannel array and amine groups was rapidly grown on a simple and low-cost indium tin oxide (ITO) electrode using the electrochemically assisted self-assembly (EASA) method. Au nanomaterials were confined in situ on the VMSF through electrodeposition, which catalyzed both the conversion of dissolved oxygen (O2) to reactive oxygen species (ROS) and the oxidation of a luminol emitter and improved the electrode active surface. The ECL signal was enhanced fivefold after Au nanomaterial deposition. The recognitive interface was fabricated by covalent immobilization of the CEA antibody on the outer surface of the VMSF, followed with the blocking of non-specific binding sites. In the presence of CEA, the formed immunocomplex reduced the diffusion of the luminol emitter, resulting in the reduction of the ECL signal. Based on this mechanism, the constructed immunosensor was able to provide sensitive detection of CEA ranging from 1 pg·mL-1 to 100 ng·mL-1 with a low limit of detection (LOD, 0.37 pg·mL-1, S/N = 3). The developed immunosensor exhibited high selectivity and good stability. ECL determination of CEA in fetal bovine serum was achieved.

Optimization of culture conditions for HBV-specific T cell expansion in vitro from chronically infected patients

BackgroundHepatitis B virus (HBV) clearance depends on an effective adaptive immune response, especially HBV-specific T cell-mediated cellular immunity; however, it is difficult to produce enough HBV-specific T cells effectively.ResultsIn this work, we investigated the proportions of stimulated cells, serum, and culture media as the three primary factors to determine the most effective procedure and applied it to HLA-A2 (+) people. In parallel, we also examined the correlation between clinical parameters and HBV-specific immunity. Concerning amplification efficiency, 4 × 105 cells stimulation was superior to 2 × 106 cells stimulation, AIM-V medium outperformed 1640 medium, and fetal bovine serum (FBS) exceeded human AB serum under comparable conditions. As expected, this procedure is also suitable for developing HBV-specific CD8 + T cells in HLA-A2(+) individuals. Expanded HBV-specific T cell responses decreased with treatment time and were negatively correlated with HBV DNA and HBsAg. Furthermore, the number of HBV-specific IFN-γ + SFCs was strongly correlated with the ALT level and negatively correlated with the absolute lymphocyte count and the ALB concentration.ConclusionsWe confirm that stimulating 4 × 105 PBMCs in AIM-V medium supplemented with 10% FBS is the best approach and that HBeAg, HBsAg, and ALB are independent predictors of HBV-specific T-cell responses.

Serum-free medium for recombinant protein expression in insect cells.

The baculovirus expression vector system (BEVS) has been widely used to produce recombinant proteins because of several advantages, such as eukaryotic post-translational modifications similar to those in mammalian cells, high expression levels and safety, and large gene capacity. Usually, insect cell culture requires 5%‒10% fetal bovine serum, which has many adverse effects, including high cost, heterogeneity between batches, complex composition, and pollution risks. Therefore, serum-free medium (SFM) is indispensable for the production of recombinant proteins in insect cell culture. Here, the most commonly used insect cell lines and three insect cell media, namely basic medium, SFM, and chemically defined medium, are summarized. The basic components of insect cell SFM are similar to those of other cells but contain special components. The components, functions, and issues of different SFM used for insect cell culture are reviewed. In recent years, some special additives have been demonstrated to increase recombinant protein expression yield and quality in BEVS, and the functions and possible mechanisms of small-molecule additives are reviewed herein. Finally, future perspectives of SFM used in BEVS for recombinant protein production are discussed.

A unique and convenient electrochemical biosensor for sodium based on a Na+-pumping rhodopsin

Sodium ion (Na+) detection plays a crucial role in various fields, including clinical diagnostics, environmental monitoring, and food quality control. However, existing techniques often lack sensitivity, selectivity, or practicality. This study presents a novel protein-based electrochemical biosensor for selective and quantitative Na+ detection, utilizing the microbial rhodopsin Nonlabens dokdonensis rhodopsin 2 (NdR2) reconstituted into liposome nanoparticles and immobilized on indium tin oxide (ITO) electrodes. Upon light illumination, the biosensor generates photocurrents proportional to the Na+ concentration in the sample. Extensive characterization unveiled the biosensor’s remarkable selectivity towards Na+ over other cationic species, including K+, Ca2+, Mg2+, and Cs+. Quantitative analysis revealed two linear response ranges: 2–50 mM and 50–200 mM, with a detection limit of 75 μM. The biosensor demonstrated exceptional thermal stability, withstanding 50 °C for 90 min with minimal signal deterioration. Long-term storage stability tests further highlighted its robustness, with consistent Na+ response for up to 17 days. Furthermore, the biosensor successfully detected Na+ in fetal bovine serum, although with a distinct photocurrent profile potentially influenced by interfering components. This pioneering work introduces a highly selective, sensitive, and stable protein-based biosensor for Na+ detection, offering promising implications for diverse applications in clinical diagnostics, environmental monitoring, and quality control, while paving the way for further advancements in biosensing technologies.

The Anisotropic Mechanical and Tribological Behaviors of Additively Manufactured (Material Extrusion) Implant-Grade Polyether Ether Ketone (PEEK)

In this study, we investigated the mechanical and tribological properties of the layer-by-layer structure of additively manufactured implant-grade Polyether Ether Ketone (PEEK) through the Material Extrusion (ME) process as a potential substitute for artificial joints. The effective elasticity modulus of the anisotropic 3D-printed PEEK was determined to be 2.505 GPa along the vertical and horizontal build orientations. The lubricated friction and wear performance were assessed using a pin-on-disk test under various loads, including 14, 30, 50, and 70 N, with a sliding speed of 50 mm/s over a total distance of 1 km at 37 °C. The contact parameters between the hemispherical steel pin and 3D-printed PEEK disks, involving contact pressures over the circle of contact, were observed to increase as the load increased. The results indicated that the wear coefficient exhibited a rise from 1.418 × 10−5 to 2.089 × 10−1 as the applied loads increased, signaling a shift from mild to severe wear regimes. Fetal Bovine Serum (FBS) as a lubricant exhibited a mixed mechanism, ascertained through the Stribeck curve, as well as a minimum fluid film thickness of 1.346 nm under an isoviscous–elastic regime, as calculated by the maximum load. Moreover, the mechanism governing wear during sliding, influenced by both normal axial and shear loads, primarily involved adhesion.

Co-Assembled Nanosystems Exhibiting Intrinsic Fluorescence by Complexation of Amino Terpolymer and Its Quaternized Analog with Aggregation-Induced Emission (AIE) Dye.

Aggregation-induced emission dyes (AIEs) have gained significant interest due to their unique optical properties. Upon aggregation, AIEs can exhibit remarkable fluorescence enhancement. These systems are ideal candidates for applications in bioimaging, such as image-guided drug delivery or surgery. Encapsulation of AIEs in polymeric nanocarriers can result in biocompatible and efficient nanosystems. Herein, we report the fabrication of novel nanoaggregates formulated by amino terpolymer and tetraphenylethylene (TPE) AIE in aqueous media. Poly(di(ethylene glycol) methyl ether methacrylate-co-2-(dimethylamino)ethylmethacrylate-co-oligoethylene glycol methyl ether methacrylate), P(DEGMA-co-DMAEMA-co-OEGMA) hydrophilic terpolymer was utilized for the complexation of the sodium tetraphenylethylene 4,4',4″,4‴-tetrasulfonate AIE dye. Fluorescence spectroscopy, physicochemical studies, and self-assembly in aqueous and fetal bovine serum media were carried out. The finely dispersed nanoparticles exhibited enhanced fluorescence compared to the pure dye. To investigate the role of tertiary amino groups in the aggregation phenomenon, the polymer was quaternized, and quaternized polymer nanocarriers were fabricated. The increase in fluorescence intensity indicated stronger interaction between the cationic polymer analog and the dye. A stronger interaction between the nanoparticles and fetal bovine serum was observed in the case of the quaternized polymer. Thus, P(DEGMA-co-DMAEMA-co-OEGMA) formulations are better candidates for bioimaging applications than the quaternized ones, presenting both aggregation-induced emission and less interaction with fetal bovine serum.

Cobalt vanadate intertwined in carboxylated multiple-walled carbon nanotubes for simultaneous electrochemical detection of ascorbic acid, dopamine and uric acid

Low-cost transition metal vanadate-based electrochemical sensors have attracted a lot of attention recently. A cobalt vanadate and carboxylated multi-walled carbon nanotube composite (CoV/MWCNTs-COOH) was prepared by an ultrasonic-assisted assembly method. The uniform and dense MWCNTs-COOH attached to the surface of CoV not only combines the large surface area and superior conductivity of MWCNTs-COOH with the excellent electrochemical activity of CoV, but also enhances the redox reaction between CoV/MWCNTs-COOH composite and the analyte through synergistic effect of hydrogen bonding and electrostatic interaction. The electrochemical behaviors of CoV/MWCNTs-COOH composite modified glassy carbon electrode (CoV/MWCNTs-COOH/GCE) were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The simultaneous electrochemical sensing of ascorbic acid (AA), dopamine (DA) and uric acid (UA) on CoV/MWCNTs-COOH/GCE possesses good peak current signals with well-defined peak potentials. The linear ranges of AA, DA, and UA at CoV/MWCNTs-COOH/GCE are 1.0–100.0 μM, and the limits of detection (LODs; S/N = 3) are 0.4 μM, 0.03 μM, and 0.1 μM, respectively. The practicality of the designed sensor was further confirmed by the good recoveries obtained in the simultaneous measurement of actual samples including fetal bovine serum, human serum, urine, and Vitamin C tablets. Overall, the developed electrochemical sensor shows potential therapeutic applications for simultaneous determination of AA, DA and UA in biological fluids.