Range of self-tests available to buy in the United Kingdom: an Internet survey

We aimed to describe the availability in the United Kingdom of self-tests that are used to diagnose or screen for conditions without involving a health professional. A systematic Internet search identified 104 unique self-tests related to 24 named conditions including cancers, chronic conditions and infections. These self-tests require various samples including blood obtained using a lancet. The samples are processed at home with results available in minutes or sent to a laboratory for processing with results returned to the individual by e-mail or post. Prices per self-test and condition range from <1 pound to 76 pound. Self-tests are readily available, and further work is needed to assess their impact.

Biosensor based on excessively tilted fiber grating in thin-cladding optical fiber for sensitive and selective detection of low glucose concentration

We report a highly sensitive, high Q-factor, label free and selective glucose sensor by using excessively tilted fiber grating (Ex-TFG) inscribed in the thin-cladding optical fiber (TCOF). Glucose oxidase (GOD) was covalently immobilized on optical fiber surface and the effectiveness of GOD immobilization was investigated by the fluorescence microscopy and highly accurate spectral interrogation method. In contrast to the long period grating (LPG) and optical fiber (OF) surface Plasmon resonance (SPR) based glucose sensors, the Ex-TFG configuration has merits of nearly independent cross sensitivity of the environmental temperature, simple fabrication method (no noble metal deposition or cladding etching) and high detection accuracy (or Q-factor). Our experimental results have shown that Ex-TFG in TCOF based sensor has a reliable and fast detection for the glucose concentration as low as 0.1~2.5mg/ml and a high sensitivity of ~1.514nm·(mg/ml)−1, which the detection accuracy is ~0.2857nm−1 at pH 5.2, and the limit of detection (LOD) is 0.013~0.02mg/ml at the pH range of 5.2~7.4 by using an optical spectrum analyzer with a resolution of 0.02nm.