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Novel amine‐functionalized symmetrical squaraine (SQ)‐dye and fluorescein isothiocyanate (FITC)–SQ–FITC dye conjugate are designed and successfully synthesized, followed by their structural and photophysical characterizations. Symmetrical SQ dye exhibits complete fluorescence quenching in polar solvents, which is explained by considering photoinduced electron transfer (PET) as a dominant quenching pathway. In contrast, FITC–SQ–FITC dye conjugate results in a decrease in an aggregation of both SQ and FITC units and about 47 times enhancement in the far‐red fluorescence appearing at 674 nm. This profound enhancement in the far‐red fluorescence is explained by the synergistic influence of suppression of aggregation‐induced quenching (ACQ) and PET. This newly designed FITC–SQ–FITC dye conjugate shows complete quenching of the far‐red fluorescence in phosphate buffer saline (PBS) owing to very strong dye aggregation, as confirmed by spectral absorption investigation. In PBS, it strongly interacts with bovine serum albumin (BSA) (Ka = 1.1 × 104 m−1) used as a model protein breaking the dye aggregation by BSA and increasing far‐red fluorescence associated with SQ as a function of increasing BSA concentration. A profound 117 times increase in fluorescence at 674 nm with 25 times of BSA concentration suggests that the designed FITC–SQ–FITC is an excellent far‐red probe for dye‐protein interaction. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 7-month-old girl who presented because of sudden cardiopulmonary arrest. She had right facial nerve palsy from birth; the diagnosis of craniometaphyseal dysplasia (CMD) was made based on the clinical features of hypertelorism, facial nerve palsy and bony choanal stenosis. Gene analysis was performed which indicated that there was maternal somatic mosaicism for an ANKH mutation but the mother had no apparent clinical or radiological features of CMD.