Chiral MOF Derived Wearable Logic Sensor for Intuitive Discrimination of Physiologically Active Enantiomer.

Chiral sensors have attracted growing interest due to their application in health monitoring. However, rational design of wearable logic chiral sensors remains a great challenge. In this work, a dual responsive chiral sensor RT@CDMOF is prepared through in situ self-assembly of chiral γ-cyclodextrin metal-organic framework (CDMOF), rhodamine 6G hydrazide (RGH), and tetracyanovinylindane (TCN). The embedded RGH and TCN inherit the chirality of host CDMOF, producing dual changes both in fluorescence and reflectance. RT@CDMOF is explored as a dual channel sensor for chiral discrimination of lactate enantiomers. Comprehensive mechanistic studies reveal the chiral binding process, and carboxylate dissociation is confirmed by impedance and solid-state 1 H nuclear magnetic resonance (NMR). A flexible membrane sensor is successfully fabricated based on RT@CDMOF for wearable health monitoring. Practical evaluation confirms the potential of fabricated membrane sensor in point-of-care health monitoring by indexing the exercise intensity. Based on above, a chiral IMPLICATION logic unit can be successfully achieved, demonstrating the promising potential of RT@CDMOF in design and assembly of novel smart devices. This work may open a new avenue to the rational design of logic chiral sensors for wearable health monitoring applications.

Effectiveness of bisphosphonates on bone mineral density in osteopenic postmenopausal women: A systematic review and network meta-analysis of randomized controlled trials.

BACKGROUND: Various bisphosphonate agents have been proven to be effective in preventing bone loss and fracture in osteopenic postmenopausal women. This study was designed to compare the effectiveness of various BPs on preventing the loss of bone mineral density (BMD) for postmenopausal women with osteopenia. METHODS: PubMed, EMBASE, and Cochrane Central Register of Controlled Trials were screened up to identify randomized controlled trails comparing effectiveness of BPs or placebo on the BMD of postmenopausal women with osteopenia. Network meta-analysis and standard pair-wise meta-analyses were performed. The main outcomes include the percentage changes of 6-, 12-, 24-, and 36-month BMD at lumbar, total hip and femoral neck, and frequencies of new fractures and severe adverse events. RESULTS: Fourteen randomized controlled trials were eligible, involving 11,540 participants. No significant difference was presented among the available interventions for the 6-month BMD at 3 different sites, but the magnitudes of differences among the treatment regimens became gradually increased along with the extending of follow-up periods. Daily aledronate of more than 5 mg provided the maximal percentage increase on BMD of femoral neck and lumbar spine, while zoledronate provided maximal change on BMD of total hip, at different follow-up periods. This network meta-analysis also demonstrated similar frequencies of new clinical fractures and severe adverse events among different interventions. CONCLUSIONS: A ranking spectrum depicting the effectiveness on BMD percentage change following interventions with different bisphosphonate regimens was provided. Generally, regimens with zoledronate and aledronate were found to be the most effective interventions in the 3 sites at different end points.

Nanosphere [Ag(SR)]n: coordination polymers of Ag+ with a combination of hydrophilic and hydrophobic thiols.

We propose to create nanospheres in aqueous solutions from coordination polymers of Ag+ with a combination of a hydrophilic and a hydrophobic thiol, of diameter ca. 2.7 nm in the case of using cysteine and n-butanethiol. A spectral probe for the formation of the nanospheres is a reversal of the CD signal at 253 nm from negative in the case of cysteine alone to positive when cysteine and n-BuSH are both employed, together with an amplification.

Chiral Recognition by Flexible Coordination Polymers of Ag+ with a Cysteine-Based Chiral Thiol Ligand That Bears a Binding Site.

We report a new scheme for chiral recognition using coordination polymers of Ag+ with a chiral thiol ligand that contains a binding group. N-Benzoyl-l-cysteine ethyl ester equipped with a boronic acid group at the para position of the phenyl ring forms coordination polymers with Ag+ in alkaline aqueous solutions that exhibit excellent selectivity toward a d-glucose enantiomer over l-glucose, while the coordination polymers from the d-cysteine-based thiol ligand are specific for l-glucose. It is assumed that a conformation change occurs upon interaction of a saccharide molecule with the polymeric chain receptor, for which the next binding is promoted, leading to the highly effective chiral recognition, despite the flexible nature of the polymeric receptor.