Ultrasensitive detection of cancer biomarkers in the clinic by use of a nanostructured microfluidic array

Multiplexed biomarker protein detection holds unrealized promise for clinical cancer diagnostics due to lack of suitable measurement devices and lack of rigorously validated protein panels. Here we report an ultrasensitive electrochemical microfluidic array optimized to measure a four-protein panel of biomarker proteins, and we validate the protein panel for accurate oral cancer diagnostics. Unprecedented ultralow detection into the 5-50 fg·mL(-1) range was achieved for simultaneous measurement of proteins interleukin 6 (IL-6), IL-8, vascular endothelial growth factor (VEGF), and VEGF-C in diluted serum. The immunoarray achieves high sensitivity in 50 min assays by using off-line protein capture by magnetic beads carrying 400,000 enzyme labels and ~100,000 antibodies. After capture of the proteins and washing to inhibit nonspecific binding, the beads are magnetically separated and injected into the array for selective capture by antibodies on eight nanostructured sensors. Good correlations with enzyme-linked immunosorbent assays (ELISA) for protein determinations in conditioned cancer cell media confirmed the accuracy of this approach. Normalized means of the four protein levels in 78 oral cancer patient serum samples and 49 controls gave clinical sensitivity of 89% and specificity of 98% for oral cancer detection, demonstrating high diagnostic utility. The low-cost, easily fabricated immunoarray provides a rapid serum test for diagnosis and personalized therapy of oral cancer. The device is readily adaptable to clinical diagnostics of other cancers.     

Lipase‐catalyzed production of medium‐chain triacylglycerols from palm kernel oil distillate: Optimization using response surface methodology

Optimization of lipase‐catalyzed esterification for the production of medium‐chain triacylglycerols (MCT) from palm kernel oil distillate and glycerol was carried out in order to determine the factors that have significant effects on the reaction system and MCT yield. Novozyme 435 from Candida antarctica lipase was found to have the highest activity at 52.87 ± 0.03 U/g. This lipase also produced the highest MCT yield, which is 56.67%. The effect of different variables on MCT synthesis was studied with a two‐level five‐factor fractional factorial design. The various variables include (1) reaction temperature, (2) enzyme load, (3) molecular sieves concentration, (4) reaction time and (5) molar substrate ratio. Reaction temperature, reaction time and molar substrate ratio strongly affect MCT synthesis (p <0.05). However, enzyme load and molecular sieve concentration did not have a significant (p >0.05) influence on MCT yield. Therefore, the significant variables such as reaction temperature, reaction time and molar substrate ratio were further optimized through central composite rotatable design (CCRD). Comparisons between predicted and experimental values from the CCRD optimization procedures revealed good correlation, implying that the quadric response model satisfactorily expressed the percentage yield of MCT in the lipase‐catalyzed esterification. The optimum MCT yield is 73.3% by using 2 wt‐% enzyme dosage, a molecular sieves concentration of 1 wt‐%, a reaction temperature of 90 °C, a reaction time of 10 h and a molar substrate ratio of 4 : 1 (medium‐chain fatty acid/glycerol). Experiments to confirm the predicted results using the optimal parameters were conducted and an MCT yield of 70.21 ± 0.18% (n = 3) was obtained.     

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Technical news feature Palm carotenoids, tocopherols and tocotrienols     

UVC dosage effects on the physico-chemical properties of lime (Citrus aurantifolia) juice

A phenyl lipid alkaloid and seven phenolic compounds were isolated from the aerial part of Spergularia marina, a halophyte that grows on salt marshes and tidal flat. These compounds were identified as 2,4-di-tert-butylphenol, N-hexacosanoylanthranilic acid, tryptophan, 4-hydroxybenzyol glucopyranoside, luteolin 6-C-β-D-glucopyranoside 8-C-β-D-(2-O-feruloyl)glucopyranoside, luteolin 6-C-β-D-(2-O-feruloyl)glucopyranoside 8-C-β-D-glucopyranoside, apigenin 6-C-β-D-glucopyranoside 8-C-β-D-(2-O-feruloyl)glucopyranoside, and apigenin 6-C-β-D-(2-O-feruloyl)glucopyranoside 8-C-β-D-glucopyranoside. The structures were determined by nuclear magnetic resonance and electrospray ionization-mass spectroscopy.     

Assessing the usability and ergonomic considerations on communication technology for older Malaysians

Universal Access in the Information Society - The increasing elderly population and their specific needs have challenged communication technology developers regarding the usability of their...     

A dynamic modeling to measure lean performance within lean attributes

In today’s competitive world lean manufacturing has become an important “role model” for two groups: academics and practitioners. Many organizations around the world have attempted to implement it but the lack of a clear understanding of the main attributes to leanness, lean performance and its measurement contribute to the failure of lean practices. It therefore seems necessary to provide a way to evaluate the impact of lean attributes using an approach to determine the criteria and key factors of leanness. Although there are numerous theoretical and practical studies that address lean tools and techniques, few studies focus systematically on measuring the influence of lean attributes on leanness. To fill the current gap, this paper presents an innovative approach to measure the value of the influence of lean attributes on manufacturing systems by using fuzzy membership functions. A lean attributes score is finally calculated to give managers and decision makers a real insight into the leanness level and to further improve it by acting appropriately in the manufacturing system. The model is dynamic, flexible, feasible, and easy to follow and implement. It enables a systematic measurement of the influence of lean attributes by producing a final integrated unit score.     

Effects of post-drying methods on pomelo fruit peels

Process conditions of alkali refining, bleaching, and deodorization of crude chufa oil extracted from chufa (Cyperus esculentus L.) tubers grown in Korea were optimized to obtain an edible grade vegetable oil. The overall scope of refining conditions was similar to other vegetable oils. The degumming process, however, could be omitted since phospholipids were removed during alkalirefining and bleaching processes. RBD (alkali-refined, bleached, and deodorized) chufa oil fully satisfied Korean quality standards for edible vegetable oil. Chufa oil contained a high level of oleic acid, along with palmitic acid and linoleic acid. Physicochemical properties of chufa oil were similar to olive oil. The order of oxidative stability of chufa oil was crude>deodorized>degummed>refined>bleached oil. RBD chufa oil was virtually colorless and bland tasting, and was considered suitable for edible purposes.