Synthesis and Characterisation of Ligand Free Cadmium Imprinted Polymer for Sensing of Cd(II) from Aqueous Solution

Cadmium(II)-imprinted polymer [Cd(II)-IIP] was synthesized without using the conventional complexing ligand to reduce unnecessary step for complexing Cd(II). During synthesis of Cd(II)-IIP, the complete removal of Cd(II) from the polymer was confirmed using EDAX and AAS. Synthesized polymers ([Cd(II)-IIP], non-imprinted polymer (NIP) and polymer with cadmium (CdP) were also characterized and compared. SEM analysis of Cd(II)-IIP indicated the changes in surface morphology after imprinting, the polymer looked like a flaky material in comparison with NIP and CdP. BET surface area of Cd(II)-IIP (68 m2/g) was found to be more than that of NIP (24.6 m2/g) and CdP (17 m2/g). Cd(II)-IIP formed a complex with Cd(II) in the solution through carbonyl oxygen of the acrylamide as confirmed by FTIR. TGA analysis showed less char yield for Cd(II)-IIP than NIP. Cd(II)-IIP was further explored for the fabrication of ion selective electrode (ISE), which on binding with Cd(II) gave higher potential than NIP-ISE. Interference study was also performed using Cd(II)-IIP as such and also with fabricated ISE with Cd(II)-IIP using different cations such as Pb(II), Zn(II), Mn(II), Hg(II), and found that imprinted polymer showed more selectivity towards Cd(II) in aqueous solutions

Comparative scanning electron microscope analysis of diode laser and desensitizing toothpastes for evaluation of efficacy of dentinal tubular occlusion

Background: The present study aims to evaluate the efficacy of diode laser alone and in combination with desensitizing toothpastes in occluding dentinal tubules (both partially occluded and completely occluded tubules) by scanning electron microscope (SEM). Materials and Methods: Fifty human teeth were extracted, cervical cavities were prepared and etched with 17% ethylenediaminetetraacetic acid, and smear layer was removed to expose the tubules. The teeth were divided into five groups: Group I – Application of NovaMin-formulated toothpaste, Group II – Application of Pro-Argin™-formulated toothpaste, Group III – Application of diode laser in noncontact mode, Group IV – NovaMin-formulated toothpaste followed by laser irradiation, and Group V – Pro-Argin™-formulated toothpaste followed by laser irradiation. After treatment, quantitative analysis of occluded dentinal tubules was done by SEM analysis. Results: The mean values of percentages of total occlusion of dentinal tubules in Groups I, II, III, IV, and V were 92.73% ± 1.38, 90.67% ± 1.86, 96.57% ± 0.64, 97.3% ± 0.68, and 96.9% ± 6.08, respectively. Addition of diode laser (Groups III, IV, and V) yielded a significant occlusion of the dentinal tubules when compared to desensitizing toothpastes alone (Groups I and II). Conclusion: Diode laser (Group III) has shown more efficacy in occluding dentinal tubules when compared with desensitizing toothpastes which was statistically significant (P < 0.05). Among the five groups, NovaMin + diode laser (Group IV) showed the highest percentage of occluded dentinal tubules