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Glioblastoma multiforme (GBM), which is a malignant primary brain tumor, is the cancer that spreads most aggressively into the adjacent brain tissue. Patients with metastatic GBM have a poor chance of survival. In this study, we examined the anti-GBM mobility effect of small protein, called GMI, which is cloned and purified from Ganoderma microsporum. Proteomic profiles showed that GMI-mediated proteins were involved in cell motility and cell growth functions. Specifically, we demonstrated that GMI significantly suppressed cell migration and invasion of GBM cells. GMI combined with temozolomide (TMZ), which is a traditional chemotherapeutic agent for GBM treatment, synergistically inhibited motility in GBM cells. Mechanistically, we demonstrated that GMI induced proteasome-dependent degradation of Slug, which is a critical transcription factor, is frequently linked to metastasis and drug resistance in GBM. Knockdown of Slug reduced cell viability and colony formation of GBM cells but enhanced TMZ-suppressed cell migration and viability. The results of this study show that targeting Slug degradation is involved in GMI-suppressed mobility of GBM cells. Moreover, GMI may be a potential supplementary agent for the suppression of GBM.

This article addresses the synthesis of Fe3+ doped TiO2 nanoparticles with variations of molar concentrations of Fe3+ and their adequate use as potential photocatalysts for Photocatalysis applications. Synthesized photocatalysts were characterized thoroughly by different analytical techniques in terms of morphological, chemical, structural, crystalline, optical, electronic structure, surface area etc properties. The occurrence of red shift phenomenon of the energy band gap attributes to the transfer of charges and transition between the d electrons of dopant and conduction band (CB) or valence band (VB) of TiO2. The doping of Fe3+ ions generates more trap sites for charge carriers with the surface trap sites. Thorough experimental conclusions revealed that the Fe3+ ions necessarily regulate the catalytic property of TiO2 nanomaterial. The obtained total degradation efficiency rate of Methylene Blue (MB) was 93.3% in the presence of 0.1 M Fe3+ in the host material and for Malachite Green Oxalate the efficiency was 100% in the presence of 0.05 M and 0.1 M Fe3+in the host material. In both the cases the total visible light irradiation time was 90 min. The adsorption properties of the photocatalysts have been also performed in a dark for 90 min in the presence of MB dye. However, till now there are hardly reported photocatalysts which shows complete degradation of these toxic organic dyes by visible light driven photocatalysis. of potential values of valence and conduction band shows the production of active oxidizing species for hydrogen yield and the possible mechanism of the Schottky barrier has been proposed. A schematic diagram of visible light driven Photocatalysis has been pictured showing degradation activity of Fe3+-TiO2 catalysts sample.

This study investigated the effect of thermal management on the performance of vertical-cavity surface-emitting lasers (VCSELs). It was found that the thickness of silicon substrate, which can serve as the submount for VCSEL packages, has a strong influence on the thermal dissipation of on-chip laser sources, and eventually impacts on their output characteristics. Moreover, the improvements in optical characteristics of the on-chip VCSELs were the best heat dissipation through thinning silicon substrates to 50- $\mu \text{m}$ thickness combined with electroplated Cu with 100- $\mu \text{m}$ thickness. In addition, this study also performed COMSOL simulations. The simulation results were consistent with experimental results.

Osteoarthritis (OA) is a globally occurring articular cartilage degeneration disease that adversely affects both the physical and mental well-being of the patient, including limited mobility. One major pathological characteristic of OA is primarily related to articular cartilage defects resulting from abrasion and catabolic and proinflammatory mediators in OA joints. Although cell therapy has hitherto been regarded as a promising treatment for OA, the therapeutic effects did not meet expectations due to the outflow of implanted cells. Here, we aimed to explore the repair effect of magnetized chondrocytes using magnetic amphiphilic-gelatin nanocarrier (MAGNC) to enhance cellular anchored efficiency and cellular magnetic guidance (MG) toward the superficial zone of damaged cartilage. The results of in vitro experiments showed that magnetized chondrocytes could be rapidly guided along the magnetic force line to form cellular amassment. Furthermore, the Arg-Gly-Asp (RGD) motif of gelatin in MAGNC could integrate the interaction among cells to form cellular stacking. In addition, MAGNCs upregulated the gene expression of collagen II (Col II), aggrecan, and downregulated that of collagen I (Col I) to reduce cell dedifferentiation. In animal models, the magnetized chondrocytes can be guided into the superficial zone with the interaction between the internal magnetic field and MAGNC to form cellular stacking. In vivo results showed that the intensity of N-sulfated-glycosaminoglycans (sGAG) and Col II in the group of magnetized cells with magnetic guiding was higher than that in the other groups. Furthermore, smooth closure of OA cartilage defects was observed in the superficial zone after 8 weeks of implantation. The study revealed the significant potential of MAGNC in promoting the high-density stacking of chondrocytes into the cartilage surface and retaining the biological functions of implanted chondrocytes for OA cartilage repair.

Glycated albumin(GA), a biomarker which has great potential to replace glycated hemoglobin in the diagnosis and treatment of diabetes, is being extensively studied by scientists, especially in preventive medicine. Aptamers, as novel probes, have attracted much attention due to their high specificity, wide storage conditions, and simple preparation. However, the interaction mechanism between GA and its aptamer is still unclear, hindering the progress of diabetic aptamer sensors into clinical testing. In this study, the interaction mechanism between GA and its aptamer was evaluated for the first time using surface plasmon resonance by changing the pH value, salt concentration and temperature. The successful preparation of the sensor chip is proved by the water contact angle, Atomic Force Microscope, and the X-ray photoelectron spectroscopy. This study shows that the pH can greatly affect the formation of a complex from the interaction between the aptamer and GA. The interaction mechanism between GA aptamer and GA was caused by electrostatic force. Otherwise, this is the first time to detect protein isoelectric point (pI) using SPR. This study provides an important reference for researchers of aptamer sensors from the perspective of detection environment, and promotes the use of aptamer sensors to the clinic.

The spatial critical shelter sizes above which populations would survive are investigated for the infection of hantavirus among rodent populations surrounded by a deadly environment. We show that the critical shelter sizes for the infected population and the susceptible population are different due to symmetry breaking in the reproduction and the transmission processes. Therefore, there exists a shelter size gap within which the infected population becomes extinct while only the susceptible population survives. With the field data reported in the literature, we estimate that, if one confines the rodent population within a stripe region surrounded by a deadly environment with the shorter dimension between 335.5±27.2m and 547.9±78.3m, the infected population would become extinct. In addition, we introduce two factors that influence the movement of rodents, namely, the spatial asymmetry of the landscape and the sociality of rodents, to study their effects on the shelter size gap. The effects on the critical size due to environmental bias are twofold: it enhances the overall competition among rodents which increases the critical size, but on the other hand it promotes the spread of the hantavirus which reduces the critical size for the infected population. On the contrary, the sociality of rodents gives rise to a more localized population profile which promotes the spread of the hantavirus and reduces the shelter size gap. The results shed light on a possible strategy of eliminating hantavirus while preserving the integrity of food webs in ecosystems.

Extracellular matrix has an important part of the role in tissue engineering and regenerative medicine, so it is necessary to understand the various interactions between cells and extracellular matrix. Type II collagen and hyaluronic acid are the major structural components of the extracellular matrix of articular cartilage, and they are involved in fibril formation, entanglement and binding. The aim of this study was to prepare type II collagen fibrils with surface grafted with hyaluronic acid modified at the reducing end. The topographic pattern of type II collagen fibrils showed a significant change after the surface coupling of hyaluronic acid according to atomic force microscopy scanning. The presence of hyaluronic acid on the type II collagen fibrillar surface was confirmed by the specific binding of nanogold labelled with lectin. No significant increase in cell proliferation was detected by a WST-1 assay. According to histochemical examination, the maintenance of the round shape of chondrocytes and increased glycosaminoglycan secretion revealed that these cell pellets with Col II- g-hyaluronic acid molecules contained un-dedifferentiated chondrocytes in vitro. In the mixture with the 220-kDa Col II- g-hyaluronic acid copolymer, the expression of type II collagen and aggrecan genes in chondrocytes increased as demonstrated by real-time polymerase chain reaction analysis. Experimental results show that the amount of hyaluronic acid added during culturing of chondrocytes can maintain the functionality of chondrocytes and thus allow for increased cell proliferation that is suitable for tissue repair of human cartilage.

Diabetes mellitus is one of the most common noncommunicable diseases in the world. Fasting blood glucose level is one of the diabetes diagnostic criteria, but it is readily affected by stress, exercise and many other factors. Glycated hemoglobin (HbA1c) is an important clinical index for diabetes and related diseases. In this study, a cheaper, rapid-prototyping, high-sensitivity angle-scanning surface plasmon resonance (SPR) was developed by fused deposition modeling (FDM) 3D printing technology for HbA1c detection. The sensor chip is based on an aptamer that has high affinity and high specificity to HbA1c. The results showed that this HbA1c-specific aptamer had high specificity for HbA1c, and the calculated KD was 6.13 × 10−8 M. The linear detection response of HbA1c appeared in the range of 18–147 nM, with a detection limit of 1 nM. This SPR HbA1c detection system could be a promising platform for developing clinical point-of-care diagnostic applications.

Blood glucose monitoring is a valuable tool for managing diabetes. In recent years, with the increase of diabetics in the world, continuous monitoring of blood sugar changes has attracted more and more researchers’ attention. Among the current technologies for measuring glucose, optical and electrochemical glucose sensors are the mainstream ones. This article introduces the history of optical, electrochemical, and other sensors such as field effect transistors sensors and their advantages and disadvantages respectively. This review summarizes the research progress and main challenges of continuous glucose monitoring technology. We found that different optical techniques have different limitations which restricts the development of optical CGM. In contrast, electrochemical glucose sensors are more feasible and reliable in implementing CGM. Therefore, this review focuses on the development and shortcomings of electrochemical sensors, especially the promising DET and the current commercial CGM. Hopefully, it will help readers sort out the future of CGM’s development.

In recent years, with the rise of global diabetes, a growing number of subjects are suffering from pain and infections caused by the invasive nature of mainstream commercial glucose meters. Non-invasive blood glucose monitoring technology has become an international research topic and a new method which could bring relief to a vast number of patients. This paper reviews the research progress and major challenges of non-invasive blood glucose detection technology in recent years, and divides it into three categories: optics, microwave and electrochemistry, based on the detection principle. The technology covers medical, materials, optics, electromagnetic wave, chemistry, biology, computational science and other related fields. The advantages and limitations of non-invasive and invasive technologies as well as electrochemistry and optics in non-invasives are compared horizontally in this paper. In addition, the current research achievements and limitations of non-invasive electrochemical glucose sensing systems in continuous monitoring, point-of-care and clinical settings are highlighted, so as to discuss the development tendency in future research. With the rapid development of wearable technology and transdermal biosensors, non-invasive blood glucose monitoring will become more efficient, affordable, robust, and more competitive on the market.

Background We present a dynamic model for designing a rotating packed bed (RPB) demonstrating volatile organic compound absorptions with circulation. The developed RPB model can be applied for industrial process simulations and scale-up. Methods The industrial applicability of the model was validated using in-house steady-state and dynamic RPB experimental data. The absorption of acetic acid (AA) in gas stream by an RPB, evaluated using reverse osmosis (RO) water and 1 wt.% NaOH aqueous solution, established the model. The operational variables’ effects, such as rotational speed and gas to liquid ratio, on the AA absorption efficiency are discussed. Significant findings The height of transfer unit (HTU) of the RPB was less than 3 cm, indicating the superior mass-transfer efficiency of the RPB than that of conventional packed bed column. The RPB model could predict the HTU in a steady-state well for the AA absorption, and the average absolute deviations (AAD) of HTU for the absorbent using RO water and 1 wt.% NaOH solution were 19.2% and 15.2%, respectively. Furthermore, the RPB model accurately predicted the AA absorption in circulation well for 1 wt.% NaOH with initial AA loadings of 1.7, 1.9, and 2.0 wt.% and AADs of 3.5%, 1.7%, and 1.9%, respectively.

Glycated hemoglobin (HbA1c) has been widely explored as an important marker for monitoring and diagnosing diabetes. Due to the advantages of high selectivity, easy preparation, and convenient preservation of aptamers, research on glycated hemoglobin detection utilizing aptasensors has received much attention in recent years. However, factors such as the pH and the salt concentration of the solution and the structure of the aptamer could influence the interactions between HbA1c and the aptamer. In this study, the factors were evaluated using surface plasmon resonance (SPR). The results show that the pH and the salt concentration can greatly affect the formation of a complex between the aptamer and HbA1c. In the stereostructure of the aptamer, loop L1 may be an important motif for recognizing glycated hemoglobin. In addition, the best condition for detecting HbA1c was at pH 6, with a high sensitivity and a low limit of detection(LOD) (1.06 × 10−3 RU nM /2.55 nM). The results also demonstrated that the use of an SPR aptamer biosensor can be a sensitive technique to improve the accuracy and correctness of HbA1c measurement.

Polydimethylsiloxane (PDMS) is often used in flexible electronic skin, due to their non toxic and tough. However, the lack of degradation and cell biocompatibility of PDMS would limit the potential use in the biological field. To overcome the limitation, PDMS was modified by surface treatment for enhancing cell adhesion and proliferation. This research is focused on preparation and evaluation of novel chitosan biocompatible electronic skin. Chitosan electronic skin was prepared by a thermal induced phase separation method, following treatment with NaOH gelating agent, followed by analyzing the surface morphology, swelling behavior, mechanical strength, degradation rate. The electrode was produced by screen printing technique, followed by analyzing the adhesion between the ink and cell biocompatibility. From scanning electron microscope (SEM) observations, NaOH gelated chitosan skin had the smooth surface morphology. The swelling ratio of all chitosan skin gelated by NaOH were less than 5%. The chitosan skin, prepared by 300k kDa chitosan gelated by NaOH for 3hr, had the smallest swelling ratio. Furthermore, its mechanical strength showed the highest value of Young’s modulus (∼151 kPa). It indicated that 300 kD chitosan skin gelated by NaOH for 3hr had better size stability. All chitosan skins degraded about 20% of initial weight after 40 days in vitro shaking test. The adhesion strength of the silver inks on the surface of chitosan was better than carbon ink, and the electrical characteristic is almost the same with commercial polycarbonate (PC) substrate. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay and SEM observation indicated that chitosan skin with silver electrode showed the cell biocompatibility. By further increasing the application of both screen imprinting technique and biopolymer, the idea of interdisciplinary can be achieved and it would be a creative revolution to the field of wearable device into tissue engineering.

In this present study, we investigated the effect of photocatalyzation on the degradation of trichloroethylene (TCE) in the aqueous phase by a photocatalyst-coated plastic optical fiber (POF). Two light-emitting diodes (LEDs) with low light intensity were used as the light source and TiO2 and ZnO were used as photocatalysts, which were characterized by scanning electron microscope (SEM) and UV-Vis diffuse reflectance spectroscopy (DRS). The para-chlorobenzoic acid (pCBA) was used as the hydroxyl radical probe for kinetic study and for the calculation of hydroxyl radical conversion rate (ROH,UV ). Experimental results show that POF coated with TiO2 exhibited higher degradation efficiency of TCE in basic solution, but POF coated with ZnO performed better in acidic solution. The increase of coating times resulted in the decrease in degradation efficiency of TCE due to increased thickness of the photocatalyst layer. The enhancement of light intensity contributed to the improvement of photocatalytic treatment efficiency. The ROH,UV for TiO2 and ZnO coated POF increased from 2 &times, 103 to 8 &times, 103 M s cm2 mJ&minus, 1 and from 8 &times, 102 to 2 &times, 1, respectively, as the pH increased from 4 to 10.

Hydrothermal carbon (HTC) is typically well-dispersed, but it remains a great challenge for HTC to become conductive. Co-doping with heteroatoms has been confirmed to be an effective strategy to significantly promote the electrical conductivity of carbon. Moreover, there is no simple and green method to construct sensitive HTC based electrochemical biosensors until now. In this paper, N and S dual-doped carbon (NS-C) with ultra-low charge transfer resistance is easily synthesized from L-cysteine and glucose in a hydrothermal reaction system. The morphology, structural properties and electrochemical properties of the as-prepared NS-C are analyzed. In comparison with the undoped hydrothermal (UC) modified glassy carbon electrode (GCE), the charge transfer resistance of UC (476 Ω) is ten times the value of NS-C (46 Ω) . The developed biosensor shows a better performance to detect glucose in a wide concentration range (50–2500 μmol L−1) with the detection limit of 1.77 μmol L−1 (S/N=3) and a high sensitivity (0.0554 μA cm−2 μmol−1 L). The apparent Michaelis-Menten constant value of GCE/NS-C/GOx/nafion modified electrode is 0.769 mmol L−1, indicating a high affinity of glucose oxidase to glucose. These results demonstrate that the hydrothermal method is an effective way for preparing high electrical conductivity carbon with excellent performances in biosensor application.

In this study, we developed a screen-printed carbon−graphene-based electrochemical biosensor for EN2 protein detection. The engrailed-2 (EN2) protein, a biomarker for prostate cancer, is known to be a strong binder to a specific DNA sequence (5′-TAATTA-3′) to regulate transcription. To take advantage of this intrinsic property, aptamer probes with TAATTA sequence was immobilized onto the screen-printed carbon−graphene electrode surface via EDC−NHS coupling approach. Cyclic voltammetry (CV) of the electrochemical measurement technique was employed for the quantitative detection of EN2 protein. The hindrance to the redox reaction of potassium ferricyanide on the biosensor surface due to the binding of the immobilized aptamer with its target EN2 protein quantified the protein concentration. Under optimum conditions, the aptamer biosensor can detect EN2 protein over a linear range from 35 to 185 nM with a detection limit of 38.5 nM.

In the present study, ozonation and catalytic ozonation were applied in ceramic membrane ultrafiltration to investigate their effects on membrane fouling. The humic acid solution and titanium dioxide (TiO 2 ) were used as tested water and catalyst, respectively. Controlled operating parameters include ozone gas flow rate, catalyst dosage and ozone dosage. The results reveal that the permeate flux of membrane could be recovered up to 98% of the initial permeate flux when ozone gas was injected into the membrane module at the time of permeate flux decreased to 60% of the initial permeate flux. Two monitored water quality parameters, dissolved organic carbon (DOC) and UV absorbance at 254 nm (UV 254 ) were both removed up to 97% under tested experimental conditions. When TiO 2 was used as the catalyst in catalytic ozonation, the permeate flux of membrane was only recovered up to 93% of the initial permeate flux when catalysts and ozone gas were introduced into the membrane module at the time of permeate flux decreased to 60% of the initial permeate flux. However, the decrease of DOC and UV 254 achieved up to 97% and 100%, respectively. This indicates that the application of catalytic ozonation in the ceramic membrane ultrafiltration system could obtain higher permeate water quality than using ozonation alone. Both ozonation and catalytic ozonation could effectively reduce membrane fouling and maintain stable permeate flux of the tested ceramic membrane system.

OBJECTIVES To elucidate the treatment results and predictors for successful outcome in women with detrusor underactivity (DU) and stress urinary incontinence (SUI) undergoing suburethral sling procedure. METHODS Medical records of women with coexistent SUI and DU treated with a suburethral sling were retrospectively reviewed and we analyzed the association between treatment outcome and baseline demographics including etiology of DU and urodynamic variables. Patients who were dry and could urinate spontaneously were considered successful. Treatment failure was considered in those who were dry but needing clean intermittent catheterization (CIC) and patients who were still wet. Urogenital Distress Inventory (UDI-6) and Incontinence Impact Questionnaire (IIQ-7) scores were used to assess the impact of surgery on the quality of life. RESULTS Among 71 patients, a successful outcome was noted in 39 (55%), failed outcome with CIC in 15 (21%), and totally treatment failure in 17 (24%). Treatment outcome did not differ among the etiology subgroups. Overall, UDI-6 and IIQ-7 scores significantly improved after surgery. Multivariable logistic regression analysis revealed that the IIQ-7 and maximum flow rate (Qmax) were two independent predictors for improvement after surgery. An IIQ-7 score ≤6, and Qmax ≥6 mL/s can predict improvement by receiver operating characteristic analysis. Qmax ≤6 mL/s can predict needing CIC after surgery. CONCLUSIONS For women with SUI and coexistent DU who underwent suburethral sling procedure, low IIQ-7 (≤6) scores and higher Qmax (≥6 mL/s) are predictors for improvement of surgical outcome. A Qmax of

The main causes of dysfunction after a spinal cord injury (SCI) include primary and secondary injuries that occur during the first minutes, hours, to days after injury. This treatable secondary cascade provides a window of opportunity for delivering therapeutic interventions. An S/B remedy (Scutellaria baicalensis Georgi and Bupleurum scorzonerifolfium Willd) has anti-inflammatory, cytoprotective, and anticarcinogenic effects in liver or neurodegenerative diseases. The present work examined the effect of S/B on injured spinal cord neurons in cultures and in vivo. S/B effectively reduced peroxide toxicity and lipopolysaccharide stimulation in both spinal cord neuron/glial and microglial cultures with the involvement of PKC and HSP70. The effect of S/B was further conducted in contusive SCI rats. Intraperitoneal injections of S/B to SCI rats preserved spinal cord tissues and effectively attenuated microglial activation. Consistently, S/B treatment significantly improved hindlimb functions of SCI rats. In the acute stage of injury, S/B treatment markedly reduced the levels of ED1 expression and lactate and had a tendency to decrease lipid peroxidation. Taken together, we demonstrated long-term hindlimb restoration alongside histological improvements with systemic S/B remedy treatment in a clinically relevant model of contusive SCI. Our findings highlight the potential of an S/B remedy for acute therapeutic intervention after SCI.

A whole paper electro-biosensor detection platform for detecting glucose is reported. Glucose oxidase was immobilized on paper-based screen-printed carbon electrodes. The developed biosensor has an excellent electrochemical characteristic and high heterogeneous electron transfer rate constant (ks = 4.23 × 10−4). This new detection platform exhibited good amperometric responses toward glucose, with a wide linear range up to 10 mM with R2 is 0.9973 and the sensitivity is 2.07 μA mM−1. The parallel measurements of glucose by different biosensors had a low relative standard deviation of 4.26 % and demonstrated it had good reproducibility. In the interference studies, there was no significant difference with ascorbic acid or uric acid. For stability, it retained 93.9 % of its initial response after a storage period of 31 days in 4 °C. Besides, the Parkes error grid analysis was indicated that paper-based electrochemical biosensor has a good accuracy on the glucose detection.

Detection of pathogenic bacteria in dairy farms and processing plants is important for milk quality control. In this study, a simple in situ method for determining the bacterial concentration in milk was developed with an interdigitated microelectrode sensor. This method was based on a punctual measurement of the electrode–milk interface impedance change due to bacterial metabolism in the milk. The interface impedance varied predominately at low frequencies, attributed to the change on the double-layer capacitance. The detection time TD, defined as the time required to attain a −10% impedance change at 10 Hz, became a practicable means for the estimation of initial E. coli concentration in milk samples. Regression analysis resulted in a third-order polynomial relationship between the detection time and the logarithm of the initial E. coli concentration (N0, cells/ml) in a milk sample, i.e., log N0 = 11.48 – 2.33 TD + 0.288(TD)2 – 0.0154(TD)3 with R2 = 0.9988. The sensor was able to detect E. coli in milk of initial concentrations as low as 7 cells/ml. The proposed impedance sensor is suitable for determining bacterial contamination at dairy farms and processing plants.

As the number of diabetic patients increases year by year, the demand for a self-monitoring blood glucose test also increases. Additionally, more in-depth studies of blood glucose biosensors have led to increasing accuracy requirements. However, at present, most enzyme glucose sensors have difficulty solving issues related to hematocrit (HCT) interference. Most studies on anti-HCT interference in blood glucose sensing have mainly focused on correction factors, such as glucose correction, and electrical impedance or resistivity characteristics to correct the impact of HCT. In this work, we developed an anti-HCT-interference blood glucose sensor based on a fiber paper-based screen-printed carbon electrode with a mediator (potassium ferricyanide) and glucose oxidase (GOD), which were fixed through inkjet printing. When testing whole blood samples with HCT levels of 20%–70% and a fluid dropping method, the results of a consensus error grid analysis showed that 91% of the data points lied within zones A and B. The glucose sensor was exclusively designed with a 16 μL chamber in the working area of the sensor. When the testing fluid was taken in by capillary sucking, the effect of HCT was further reduced, and 95% of the data points lied within zones A and B in the consensus error grid.

Skin penetration is related to efficiencies of drug delivery or ISF extraction. Normally, the macro-electrode is employed in skin permeability promotion and evaluation, which has the disadvantages of easily causing skin damage when using electroporation or reverse iontophoresis by alone; furthermore, it has large measurement error, low sensitivity, and difficulty in integration. To resolve these issues, this paper presents a flexible interdigital microelectrode for evaluating skin penetration by sensing impedance and a method of synergistical combination of electroporation and reverse iontophoresis to promote skin penetration. First, a flexible interdigital microelectrode was designed with a minimal configuration circuit of electroporation and reverse iontophoresis for future wearable application. Due to the variation of the skin impedance correlated with many factors, relative changes of it were recorded at the end of supply, different voltage, or constant current, times, and duration. It is found that the better results can be obtained by using electroporation for 5 min then reverse iontophoresis for 12 min. By synergistically using electroporation and reverse iontophoresis, the penetration of skin is promoted. The results tested in vivo suggest that the developed microelectrode can be applied to evaluate and promote the skin penetration and the designed method promises to leave the skin without damage. The electrode and the method may be beneficial for designing noninvasive glucose sensors.

Surface plasmon resonance (SPR) is a real-time, label-free, and high-sensitive detection technology. SPR has been widely used in many applications such as biomolecular interaction analysis, environmental monitoring, and medical diagnostics. However, conventional SPR sensor systems usually require expensive equipment and complicated optics. In this paper, we have demonstrated a rapid prototyping of angle-scanning SPR for bioanalytical investigation. Rapid prototyping was attained by utilizing the FDM (fused deposition modeling) based 3D (three-dimensional) printing technology. Two rotating platforms were employed to drive the laser source and photodiode, respectively. A temperature regulation unit was incorporated to maintain the system temperature in order to reduce the temperature effect. The proposed SPR rapid prototyping yielded a refractive index resolution of 6.4×10−6 RIU (refractive index unit), and the biotin-avidin system validated the kinetics parameters measurement capability. The obtained results indicated that the FDM 3D printing has great potential for developing rapid-prototyping SPR system.

In this study, we developed an interdigitated gold microelectrode-based impedance sensor to detect Escherichia coli (E. coli) in human urine samples for urinary tract infection (UTI) diagnosis. E. coli growth in human urine samples was successfully monitored during a 12-h culture, and the results showed that the maximum relative changes could be measured at 10Hz. An equivalent electrical circuit model was used for evaluating the variations in impedance characteristics of bacterial growth. The equivalent circuit analysis indicated that the change in impedance values at low frequencies was caused by double layer capacitance due to bacterial attachment and formation of biofilm on electrode surface in urine. A linear relationship between the impedance change and initial E. coli concentration was obtained with the coefficient of determination R(2)>0.90 at various growth times of 1, 3, 5, 7, 9 and 12h in urine. Thus our sensor is capable of detecting a wide range of E. coli concentration, 7×10(0) to 7×10(8) cells/ml, in urine samples with high sensitivity.

Purpose – This paper aims to discuss the background, design and implementation of the new library instruction. When a new core curriculum for first-year students was adopted at the City College of New York in the fall of 2008, the City College Library took this opportunity to establish a new approach to teach library research to freshmen. Two library workshops were embedded into a six-credit combined content and writing course. Design/methodology/approach – This paper documents the process by which the City College Library successfully transitioned to the new system and also reflects on the theory and practice of teaching information literacy in an academic setting. Findings – Library workshops embedded within the new core curriculum have clear advantages over previous library instruction. By designing and implementing library workshops to blend with the new course, the Library has become a partner in an innovative first-year program. Practical implications – This study will provide useful information on the teaching and assessment of embedded library instruction and stimulate further thought on the role of information instruction in furthering the mission of undergraduate education. Originality/value – This paper presents opportunities to expand library instruction to the first-year seminar, the most commonly implemented curricular intervention designed for freshman students. By taking part in this important project, the Library becomes an integral participant in the initiative for retention and success for undergraduate education.

The piezoelectric biosensor have been widely used in ultra-small mass detection of biomolecular, based on PZT piezoelectric material can create a variety of compositions geometrically; it could widely develop a high-frequency resonator and measure the change of the slightest mass while improve the limited detection simultaneously. Therefore, the piezoelectric biosensor of this study was fabricated by a spin-coating method and backside etching process for improving the characteristic of piezoelectric biosensor. The result exhibited that the 250 μm × 250 μm working size has the most favorable piezoelectric characteristic. The tunability was approximately 38.56 % and it showed that reducing the substrate thickness could obtain a clear resonance signal in a range of 60 to 380 MHz. In theory calculated for gravimetric sensing, it could achieve 0.1 ng sensing sensitivity. In gravimetric sensing, the sensing range was between 50,000~100,000 CFU/ml. Sensing range was lower in clinical urinary tract infection (100,000 CFU/ml), thus demonstrating its usefulness for preventive medicine. It can understand the piezoelectric sensor of this study has potential application in the future for biomedical gravimetric sensing.

A portable impedance measurement system was used to monitor the growth of L929 cells. The interdigitating microelectrodes of our portable system were produced by microfabrication technology with a width of 8 μm, a gap of 8 μm, and a length of 500 μm. These microelectrodes provided a high electric field for AC impedance measurements. When mouse L929 cells were cultured on the electrode surface and pre-coated with poly- l -lysine, the changes in the impedance on the interdigitating electrodes represented the lag, log, and stationary phases of a typical cell growth curve. The impedance measurement result was fitted to an equivalent circuit, which showed that the capacitance signal was the major contributor to the total impedance of the cell culture. The capacitance arises from the cell capacitance, the double-layer capacitance and the capacitance of the poly- l -lysine-coated surface, and the changes in capacitance were probably due to cell proliferation and the resulting changes in cell metabolites. To make the device portable and provide rapid results, we designed a novel impedance detection system comprised of a microprocessor, an AD5933 impedance converter (IC), and the interdigitating microelectrodes. This device was successfully used to observe the changes in the metabolism and proliferation of L929 cells at different stages of cell growth with low cell concentrations. Further, the portable impedance measurement device is a useful analytical tool for monitoring cell growth. It will integrate easily with wireless circuits for applications in aseptic cell biology.