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Rational design of a molecular sensing tool is an important topic in molecular recognition, signalling, and optoelectronics that has piqued the interest of chemists, biologists, and environmental scientists. Approximately 150 years have passed since the beginning of the fluorescent chemosensor sector. Due to the paramagnetic properties of Cr3+ and Al3+, it is tough to prepare a photoluminescence plug‐in detector. Most dye‐based Al3+ sensors must be utilized in organic or mixed solvents for robust hydration of Al3+ in water. The sophisticated molecular design of sensors, conversely, allows for the detection of these metal ions in aqueous medium. The design of chemosensors using various fluorophores and their mechanisms of action have been thoroughly discussed. A literature survey covering the design of chemosensors and their mechanisms of action have been thoroughly discussed covering the period 2010–2022 and that was carried out including innovative and exemplary activities from numerous groups throughout the world that have significantly contributed to this sector. The most important advantages of these probes are their aqueous solubility and quick response with outstanding selectivity and sensitivity for temporal distribution with high fidelity of metals in living cells. [ABSTRACT FROM AUTHOR]

A new rhodamine 6G-based chemosensor (L3) was synthesized and characterized by 1H, 13C, IR and mass spectroscopy studies. It exhibited an excellent selective and sensitive CHEF-based recognition of trivalent metal ions M3+ (M = Fe, Al and Cr) over mono and di-valent and other trivalent metal ions with prominent enhancement in the absorption and fluorescence intensity for Fe3+ (669-fold), Al3+ (653-fold) and Cr3+ (667-fold) upon the addition of 2.6 equivalent of these metal ions in the probe in H2O/CH3CN (7 : 3, v/v, pH 7.2). The corresponding Kd values were evaluated to be 1.94 × 10−5 (Fe3+), 3.15 × 10−5 (Al3+) and 2.26 × 10−5 M (Cr3+). The quantum yields of L3, [L3–Fe3+], [L3–Al3+] and [L3–Cr3+] complexes in H2O/CH3CN (7 : 3, v/v, pH 7.2) were found to be 0.0005, 0.335, 0.327 and 0.333, respectively, using rhodamine-6G as the standard. The LODs for Fe3+, Al3+ and Cr3+ were determined by 3σ methods and found to be 2.57, 0.78 and 0.47 μM, respectively. The cyanide ion snatched Fe3+ from the [Fe3+–L3] complex and quenched its fluorescence via its ring-closed spirolactam form. Advanced level molecular logic devices using different inputs (2 and 4 input) and a memory device were constructed. [ABSTRACT FROM AUTHOR]

A Cu(ii) based sensor (1) prepared by the complexation between (quinolin-8-ylamino)-acetic acid hydrazide (L2) and Cu2+ ions has been developed for a highly sensitive and selective recognition of HNO and S2− over other biologically abundant anions with prominent enhancement in absorption and emission intensities. The sensor (1) shows weak fluorescence due to ET (electron transfer) but upon addition of HNO and S2− a large enhancement in the fluorescence intensity (F.I.) was observed over other possible competitive anions on the basis of reduction of Cu(ii) to Cu(i) and formation of CuS, respectively. The 1 : 1 complexation was characterized by mass spectrometry (MS), elemental analysis and Job's plot. The corresponding Kf value was evaluated to be (4.934 ± 0.05) × 104 M−1 for Cu2+ from UV-Vis absorption titration. Quantum yields of L2 and [Cu-L2 + S2−] and [Cu-L2 + HNO] complexes in acetonitrile (CH3CN) are found to be 0.107, 0.09 and 0.07, respectively, using quinine sulphate as the standard. [ABSTRACT FROM AUTHOR]

A sensor (HL5) based on rhodamine 6G–en and 3-(3,5-dimethyl-pyrazol-1-ylmethyl)-2-hydroxy-5-methyl-benzaldehyde (HL4) has been developed for a highly sensitive and selective CHEF based recognition of trivalent metal ions M3+ (M = Al, Fe and Cr) over mono- and di-valent and other biologically abundant trivalent metal ions with prominent enhancement in absorption and emission intensities. A large enhancement of fluorescence intensities for Fe3+ (21 fold), Al3+ (14 fold) and Cr3+ (10 fold) was observed upon addition of 1.8 equivalents of these metals into the probe in methanol/H2O (1 : 1, v/v, pH 7.2) with the possibility of naked eye detection. The corresponding Kf values were evaluated to be 6.7 × 104 M−1 (Fe3+); 8.2 × 104 M−1 (Al3+) and 6.0 × 104 M−1 (Cr3+). The quantum yields of HL5 and [HL5–Fe3+] and [HL5–Cr3+] and [HL5–Al3+] complexes in methanol/H2O (1 : 1, v/v, pH 7.2) are found to be 0.013, 0.290, 0.120, and 0.158, respectively, using rhodamine-6G as the standard. The LOD for Fe3+, Al3+ and Cr3+ were determined by 3σ methods with values 0.29, 0.34 and 0.31 μM, respectively. An arsenate ion snatches Al from the Al–HL5 complex and quenches its fluorescence via its ring closed spirolactam form. Advanced level molecular logic devices using the inputs 2 and 4 and memory devices, have been constructed. The low cytotoxicity and large enhancement in fluorescence intensity of HL5 upon complexation with M3+ metal ions make the probe suitable for bio-imaging of M3+ (M = Al, Fe and Cr) in living cells and native cellular iron pools. [ABSTRACT FROM AUTHOR]

A diformyl-p-cresol (DFC)-8-aminoquinoline based dual signaling probe was found to exhibit colorimetric and fluorogenic properties on selective binding towards Mg2+ and Zn2+. Turn-on fluorescent enhancements (FE) as high as 40 fold and 53 fold in 9 : 1 MeCN/water (v/v) at pH 7.2 in HEPES buffer for Mg2+ and Zn2+, respectively, were observed. The binding constants determined from the fluorescence titration data are: K = (1.52 ± 0.21) × 105 M−1 and (9.34 ± 4.0) × 103 M−2 at n = 1 and 0.5, for Mg2+ and Zn2+, respectively. The L : M binding ratios were also determined by Job's method, which support the above findings. This is further substantiated by HRMS analysis. Due to solubility in mixed organo-aqueous solvents as well as cell permeability it could be used for the in vitro/in vivo cell imaging of Mg2+ and Zn2+ ions with no or negligible cytotoxicity. This probe could be made selective towards Mg2+ over Zn2+ in the presence of TPEN, both under intra- and extracellular conditions and is superior to other Mg2+ probes which suffer from selectivity of Mg2+ over Ca2+ or Zn2+. Furthermore the dissociation constant (Kd = 6.60 μM) of the Mg2+-(DFC-8-AQ) complex is far lower than the so far reported Mg2+ probes which fall in the mM range. [ABSTRACT FROM AUTHOR]

A new rhodamine-based dual signaling probe ( L3) has been found to display quick responses through visible colorimetric changes as well as fluorogenic properties on selective 1:1 binding to Hg2+, as delineated by absorption and fluorescence titrations as well as by Job′s method and ESI-MS+ studies. The fluorescent probe L3 displays a 252-fold fluorescence enhancement on binding to Hg2+. A Benesi-Hilderband fit of the absorption titration data gives Kd = (32.01 ± 0.74) μ M and a 1:1 binding stoichiometry. Owing to its solubility in mixed organic/aqueous solvents as well as its cell permeability, L3 could be used for in vitro/in vivo cell imaging of Hg2+ with no or negligible cytotoxicity. The detection limit of Hg2+ was calculated by the 3σ method to be 9.28 ng L-1. Moreover, the fluorescence of the L3-Hg2+ system was turned off and its red colour disappeared when KI was added. Thus, the 'OFF-ON-OFF' fluorescence sensing behaviour of L3 observed in the presence of Hg2+ and I- may find applications in devices with logic gate functions. [ABSTRACT FROM AUTHOR]

A 3-year-old girl with Pierre Robin Syndrome, having complaints of respiratory distress in supine position and disturbance during sleep due to airway obstruction, was scheduled for adenoidectomy. After ensuring all available precautionary measures along with facilities for emergency tracheostomy, gas induction without muscle relaxation was done in a posture at where her respiratory distress was least. The glottis could not be visualized by direct laryngoscopy in any way. Consecutive three attempts were failed and intubation was successful on fourth attempt with a gum elastic bougie. Then after curarisation, adenoidectomy was performed. Five teeth were avulsed during the instrumentations, 4 out of 5 could be recovered. Fluoroscopic screening located the 5th tooth in right main bronchus. The patient was reversed and kept on spontaneous breathing with ETT in situ. On 1st POD, gas induction was done for removal of the lost tooth. ETT was removed and with muscle relaxation, rigid bronchoscopy was attempted without success. Repeated attempts were made with intermittent ventilation and at one stage bag-mask ventilation became impossible with sharp fall of SpO2 , even down to zero for a while. Emergency tracheostomy was asked for and a needle cricothyroidectomy was done immediately. The patient had a period of anoxia during establishment of safe airway through tracheostome. After ensuring a safe airway through tracheostomy and stabilization of her vital parameters, rigid bronchoscopy was performed through tracheostome and the tooth was removed. Adequate spontaneous ventilation was achieved on the next morning without any neurological deficit. Tracheostome was closed on 8th POD under general anaesthesia and the patient was discharged with excellent cure of her symptoms and kept on regular follow-up in ENT OPD. [ABSTRACT FROM AUTHOR]

The article discusses the issues related to medication errors along with several cases related to the same and mentions that spinal needle with prefilled syringe can prevent medication error. It mentions that medical errors should be prioritised as critical public health problem. It also mentions the causes of errors which includes look‑alike drug labels, fatigue and human errors.

A letter to the editor is presented in response to the article "Cost Effective Preoperative Evaluation" is presented.