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Objective This study conducted a preliminary examination of the effects of three-area laser-assisted zona thinning (LAZT) during the cleavage stage of embryo development on the hatching process in human in vitro fertilization-embryo transfer (IVF-ET) with subjects of advanced female age or frozen-thawed (FT) embryos. Methods Eight-cell stage embryos were treated with LAZT in three areas of the zona pellucida at 120° intervals. The control group was embryos without LAZT. Of the 72 consecutive fresh cycles and the 28 FT embryo transfer cycles, the patients in 55 fresh cycles and 17 FT cycles declined LAZT, and those cycles were defined as the control group. Results In the fresh cycles, the pregnancy rates were similar in the LAZT and control groups. However, in the FT cycles, the pregnancy rate was significantly higher in the LAZT group than in the control group (45.5% in the LAZT group vs. 23.5% in the control group, p Conclusion These results show that multi-area LAZT resulted in significantly improved pregnancy outcomes in human 8-cell embryos compared to controls.

A new strategy to modulate the detection range of a molecular beacon aptamer (MBA)/conjugated polyelectrolyte (CPE)-based adenosine triphosphate (ATP) assay is suggested. The hairpin type probe, MBA contains the ATP-specific aptamer sequence in a loop part and a green fluorophore (6-carboxyfluorescein, 6-FAM) and quencher (4-((4-(dimethylamino)phenyl)azo)benzoic acid) at both termini of stem parts. Three kinds of water-soluble poly(fluorene-phenylene) based CPEs (MP2–MP6) were synthesized by varying the number of cationic groups (2 to 6) per repeat unit. In the absence of ATP, the hairpin MBA is transformed into open-chain conformation by forming a linear electrostatic complex with CPE, enabling facile fluorescence resonance energy transfer from blue-emitting CPEs to 6-FAM in MBA. In the presence of ATP, MBA forms a G-quadruplex with ATP where the close contact between the fluorophore and quencher results in the quenched PL signal of 6-FAM. The binding interaction between the aptamer and ATP in the G-quadruplex shows resistance to the structural opening by CPEs and the ionic density of CPEs was proved to have an important role in the structural transformation of the ATP-MBA G-quadruplex into the linear open-chain MBA/CPE complex. By increasing the ionic density of CPEs, structural transformation toward open-chain MBA/CPE complexes was accelerated due to enhanced electrostatic interaction between the MBA and CPE, resulting in a detection range shift to a higher [ATP]. By simply modifying the number of ionic groups in CPE, the population shift toward open-chain MBA/CPE demonstrates the successful tuning of detection range from nanomolar up to millimolar concentrations of ATP.