Fabrication and evaluation of a portable and reproducible quartz crystal microbalance immunochip for label-free detection ofβ-lactoglobulin allergen in milk products

In this study,a label-free,portable and reproducible immunochip based on quartz crystal microbalance(QCM)was developed for the qualitative detection ofβ-lactoglobulin(β-LG),an allergen,in milk products.Experimental parameters in the fabrication and regeneration procedure such as pH of the coupling microenvironment,amount of anti-β-LG antibody and regeneration reagent were optimized in detail.Under optimal conditions,the proposed QCM immunochip exhibited good recognition of β-LG,with a calibration curve of ΔF=12.877 C_(β-LG)^(0.4809)(R^(2)=0.9982)and limit of detection of 0.04μg/mL.Additionally,this portable QCM immunochip had good stability,high specificity,and no obvious cross-reaction to three other milk proteins(α-casein,α-lactalbumin,and lactoferrin).It could compete a qualitative measurement within5 min,and could be reused at least ten times.In the β-LG analysis of actual milk samples,the developed QCM immunochip yielded reliable and accurate results,which correlated strongly with those from the standard HPLC method(R^(2)=0.9969).Thus,the portable,stable,and reproducible QCM immunochip developed in this study allowed the rapid,cost-effectively and sensitively measure theβ-LG in milk products.

Oxygen and Glucose Transportation and Distribution on 3D Osteochondral Scaffold in Silico Model

Nutrients supply especially like nutrients and oxygen play vital role in tissue engineering process.It is found that tissue could not grow very well in the middle of the scaffold because few nutrients could transport to the middle.Nutrient limitations would reduce cell proliferation and differentiation.In that case,there is urgent need to understand the nutrient distribution for both in vitro and in vivo study,as no technology is able for researchers to observe the nutrients transport during those process.In this paper,a numerical model coupling with VOF(volume of fluid)model and species transport model together for predicting the distribution of oxygen and glucose in the scaffold after implantation in to the site is developed.Comparing with our previous in vivo tests,the regenerated tissue distribution has a similar trend as oxygen distribution rather than glucose.The reported scaffold manufactured by additive manufacturing provided a good interconnected structure which facilitated the nutrient transportation in the scaffold.Considering nutrient transportation,this numerical model could be used in better understanding the nutrients transportation in the scaffold,and leading to a better understanding of tissue formation in the scaffold.