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Dielectric spectroscopy measurements of conductivity were applied for understanding the change in the internal morphology of the neutral and permanently charged polyacrylamide (PAAm) hydrogels during the swelling process. For the first time four distinct peaks (each corresponding to a different swelling stage) in the conductivity of the neutral gel were observed during the swelling of this gel. These peaks are related to the distribution of dense polymer regions (they are defined as the "blobs") appearing in a microstructure of the given PAAm gel having at least four average sizes. For the charged gel the heterogeneity decreases due to the internal electric field of the charged sites. Thus, this characteristic behavior in the conductivity becomes almost negligible for the gel charged with permanent SO(3) (-) groups. It seems this fact causes considerable decrease in amplitude of the peaks and overall decrease the conductivity during the whole swelling process especially at high frequencies. The new theory of dielectric relaxation based on the fractional kinetics containing the complex power-law exponents was used for verifying these swelling processes and received an excellent confirmation in description of the real part of the complex conductivity Re[sigma(omega)] by the fitting function that follows from the suggested theory. The calculated power-law exponents describe the behavior of Re[sigma(omega,mm(0))] in the available frequency range (30 Hz-13 MHz) and for all values of the relative masses (volumes) measured in the process of the experiment. The excellent coincidence between the new theory and measured data gives a possibility to suggest more reliable physical picture of the swelling process that takes place in neutral/charged gels.

Real-time fluorescence measurements have been developed for measuring the fractal dimension d_{f} and critical exponents gamma and beta simultaneously during the sol-gel transition of acrylamide bisacrylamide cross-linking copolymerization. We observed that d_{f} passes through a minimum value of approximately 2.5 at a critical time t_{c} and crossover to 3 above it. The exponents gamma and beta , measured at t_{c} , were found to be around 1.8 and 0.45, respectively. All parameters d_{f} , beta , and gamma measured at the critical point t_{c} agree with three-dimensional percolation results.

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Quantum dots (QDs) are significant fluorescent materials for energy transfer studies with phthalocyanines (Pcs) and phthalocyanine (Pc)‐like biomolecules (such as chlorophylls). Carbon‐based QDs, especially, have been used in numerous studies concerning energy transfer with chlorophylls, but the numbers of studies concerning energy transfer between phthalocyanines and carbon‐based QDs are limited. In this study, peripherally, hydroxythioethyl terminal group substituted metal‐free phthalocyanine (H2Pc) and zinc phthalocyanine (ZnPc) were noncovalently (electrostatic and/or π–π interaction) attached to carbon QDs containing boron and nitrogen to form QD‐Pc nanoconjugates. The QD‐Pc conjugates were characterized using different spectroscopic techniques (Fourier transform infrared spectroscopy and transmission electron microscopy). The absorption and fluorescence properties of QD‐Pc structures in solution were studied. It was found that the quantum yields of the QDs slightly decreased from 30% to 25% upon doping the QDs with heteroatoms B and N. Förster resonance energy transfer efficiency was calculated as 33% for BCN‐QD/ZnPc. For the other conjugates, almost no energy transfer from QDs to Pc cores was observed. It was shown that the energy transfer between QDs to Pc cores was completely different from the energy transfer between QDs and photosynthetic pigments, and therefore we concluded that heteroatom doping in the QD structure and the existence of zinc metal in the phthalocyanine structure is obligatory for an efficient energy transfer.