Molecularly imprinted polymer based on MWCNTs-QDs as fluorescent biomimetic sensor for specific recognition of target protein

A novel molecularly imprinted optosensing material based on multi-walled carbon nanotube-quantum dots (MWCNT-QDs) has been designed and synthesized for its high selectivity, sensitivity and specificity in the recognition of a target protein bovine serum albumin (BSA). Molecularly imprinted polymer coated MWCNT-QDs using BSA as the template (BMIP-coated MWCNT-QDs) exhibits a fast mass-transfer speed with a response time of 25 min. It is found that the BSA as a target protein can significantly quench the luminescence of BMIP-coated MWCNT-QDs in a concentration-dependent manner that is best described by a Stem-Volmer equation. The K-SV for BSA is much higher than bovine hemoglobin and lysozyme, implying a highly selective recognition of the BMIP-coated MWCNT-QDs to BSA. Under optimal conditions, the relative fluorescence intensity of BMIP-coated MWCNT-QDs decreases linearly with the increasing target protein BSA in the concentration range of 5.0 x 10(-7)-35.0 x 10(-7) M with a detection limit of 80 nM.

Relationship between post-awakening salivary cortisol and melatonin secretion in healthy participants

We report the relationship between patterns of post-awakening salivary melatonin and cortisol secretion in healthy participants (n=51; mean age 21.6 ±5.0 years). Saliva samples were collected within the domestic setting, at 0-, 15-, 30-, and 45-min post-awakening on 2 consecutive typical weekdays. Analyses were undertaken on data with electronically verified sample timing accuracy (55-min delay between awakening and the start of saliva sampling). Melatonin secretion declined linearly by an average of 29% within the first 45-min post-awakening. In contrast, there was a marked 112% surge in cortisol, characteristic of the cortisol awakening response. No day differences in melatonin or cortisol secretion were observed but melatonin concentrations were lower with later awakening. Despite contrasting post-awakening changes in these hormones, there was a lack of relationship between overall levels or patterns of melatonin and cortisol during this period.