数据库

我的一个学生曾经一度因为不习惯研究生的生活而想放弃研究生的学习。回去休息了一段时间后，最近她给我来了一封信。信写得很好，我觉得她的经历和思考有普遍意义。在征得她的同意后，登载在这里。俞老师：十月初给您写信的时候，我刚回家休息两个月，心情仍旧十分低落和沮丧，毕竟是以逃兵的形式败下阵来了，觉得自己就是一个彻头彻尾的失败者。加上父母看到我每天精神不振地呆在家里，很是着急，也给了我很大的压力，希望我可以早点做出决定，结束 ...

Fiberoptic fluorescence signal transmission has several advantages for immunosensor design: physical flexibility for remote sensing, no risk of electrical interference, high signal-to-noise ratio with little attenuation over distance, and the capacity to both measure sev ...

The quantitative detection of galactose or galactose-containing saccharides is of great importance in the food industry and in medical monitoring and treatment, as much as in ascertaining the basis of disease processes. For example, it was reported that disturbed galactose metaboli ...

Evanescent wave immunobiosensors use antibodies immobilized at the surface of a waveguide to form a sensing device. Fluorescence-based evanescent wave biosensors form a fluorescent complex at the surface of the waveguide when the antigen of interest is present (e.g., a sandwich assay or ...

New recent developments in engineering have improved transducer piezoelectric technology and have led to a new generation of sensor devices, the piezoelectric microbalances, based on planar microfabrication technique. These devices show a very high sensitivity (up to femtomo ...

The use of antibodies as recognition elements in bioanalytical assays can be traced back to the late 1950s. Yalow and Berson (1) pioneered radioimmunoassay for measurement of insulin and in the followmg year Ekins (2) used this technique to measure thyroxine. Reports involving the use of antib ...

Interaction between molecules is the basis for life in cells and higher organisms. Detailed investigations of the intimate relationship between the structural properties of interacting molecules and then biological function, and the biological consequences of their interac ...

The Cytosensor, a silicon-based microphysiometer system, is a light-addressable potentiometric biosensor (LAPS) that detects functional responses of living cells in minutes. Thus, unlike other biosensors that detect and quantitate an analyte, the Cytosensor reports on the eff ...

Biosensors based on isolated receptors, together with planar bilayer lipid membranes (BLMs), provide a highly sensitive and selective sensing method for bioactive substances. Although isolation of receptors from mammals is necessary for designing the sensors, the sensors are ea ...

During the last 10 years, there have been a number of applications of liposome reagents in various immunoasay and sensor systems. These analytical systems span a range of analyte detection for agricultural (1), environmental (2), and clinical interests (3–5). Furthermore, similar bilayer ...

Calorimetric sensing or thermometric sensing involving immobilized biocatalysts has diversified into several areas of apphcatlon since its introduction in the early 1970s. In principle, a chemical or biological process is monitored and quantified by the changes in the thermal si ...

The so-called ion-step method represents a newly developed measurement concept for potentiometric detection and quantification of adsorbed biomolecules in which modified ion-sensitive field-effect transistors (ISFETs) are used. The ion-step method is based on a dynamic mea ...

The intercalation of polyaromatic compounds by DNA can serve as a basis for a simple and sensitive method for detection and quantification of carcinogens. The experimental technique is based on monitoring the decrease of polarization, caused by the displacement of an intercalated fluo ...

Ion-selective electrode (ISE) methods generally require large volume samples of more than a few milliliters. Therefore, it is highly desirable to devise a simple system for the ISE method to analyze ultratrace amounts of substances in a few microliters of sample solution. This chapter desc ...

Neurotransmitter and hormone receptors serve as biosensors for specific chemical signals ranging from low-mol-wt compounds to complex polypeptides. On binding of the target transmitter or hormone, signal amplification and transduction in biologic systems occurs via a variety ...

Immunosensors based on grating couplers belong to the group of direct optical affinity sensors (1). They allow label-free monitoring not only of lmmunoaffinity reactions, i.e., of antigen (hapten)-antibody-binding (2–8), but also of receptor—ligand-(9), protein—lipid (10, 11), and pro ...

Solid tumors have an acidic extracellular environment and an altered pH gradient across their cell compartments. Nanoparticles responsive to the pH gradients are promising for cancer drug delivery. Such pH-responsive nanoparticles consist of a corona and a core, one or both of which resp ...

Oral drug delivery is the largest and the oldest segment of the total drug delivery market. It is the fastest growing and most preferred route for drug administration. Use of hydrophilic matrices for oral extended release of drugs is a common practice in the pharmaceutical industry. This chapter ...

This is an overview of drug delivery systems (DDS), starting with various routes of drug administration. Various drug formulations, as well as devices used for drug delivery and targeted drug delivery, are then described. Delivery of proteins and peptides presents special challenges. Na ...

Adeno-associated virus (AAV) is one of the most promising viral gene transfer vectors that has been shown to effect long-term gene expression and disease correction with low toxicity in animal models, and is well tolerated in human clinical trials. The surface of the AAV capsid is an essential com ...