Luminescent markers

Enclosure also changes the redox properties of a compound, its color, and other physical properties (1,2). On this basis nonlinear optical materials, luminescence markers, controlled light switches, and other high-tech devices might be designed and prepared (15,17,137). 

This was qualitatively shown in investigations of conformational behaviour and intramolecular mobility (IMM) of cholesterol-containing polymers in dilute solutions as of a function of solvent quality 134-136,185-l88) and temperature. Polarization luminescence provides one of the most fruitful methods for the evaluation of IMM l75,176). The method permits to get direct information about rotational mobility of the macromolecule as a whole, as well as about the mobility of the main chains and side branches. This is achieved via the attachment to macromolecules of so called luminescent markers (LM) — anthracylacyloxymethane groups in the case reported. Below are shown the chain fragments with LM which give information on the mobility of main chains (LM-1) and of side groups (LM-2) ... 

The third International Dendrimer Symposium took place at Berlin Technical University in 2003. Interdisciplinary lectures demonstrated the extent to which dendritic molecules branch ouf into other areas of science, such as physics, biology, medicine, and engineering. The possibilities of functionalisation and resulting applications in industry were at the focus of this symposium. For example, nano-dimensioned dendrimer-based contrast agents were presented as multilabels for visualisation of blood vessels (see Chapter 8). Potential applications of dendritic materials as luminescence markers in diagnostics attracted lively interest (see Chapter 8). Consideration of the differences between dendrimers and hyperbranched polymers from the viewpoint of their cost-favourable application was also a topic of discussion [18]. 

Addition of tta anions to a Eu +-containing Schiff s base macrocycle increases the luminescence intensity markedly ". The tta anion coordinates to the europium macrocycle without disrupting the macrocyclic structure. A protocol for the use of these systems as luminescent markers for cytological imaging has been developed. A new -diketone that can be used to determine estrogens was developed by Matsumoto and coworkers and had detection limits between 0.60 and 0.65 ngmL . ... 

The use of the quantitiesand r is based on physical rather than formal reasons, since these quantities are additive when several types of luminescent markers exist exhibiting luminescence in the same spectral range but characterized by different values of other parameters of PL (such as limiting polarization, times of rotational mobility and the duration of the afterglow). 

The analysis of experimental data on the micro-Brownian motion in polymer chains and the theory of relaxation phenomena in polymers (see Sect. 5) show that the Brownian motion of an oscillator in a luminescent marker covalently bonded to the chain obeys a more complex time law than Eq. (1.2.3). According to the theory of the relaxation processes, for a non-inertial physical system, the decay of will described by a spectrum of relaxation times (or, more precisely,... 

Equation (1.2.10) has been derived by Weber l for a mixture of molecules (proteins) of various types with different rotatory diffusion times t/ (or different volumes Vj) and the numerical contribution of a given sort fj bearing identical luminescent markers with the duration of emission Tf. 

Polarized Luminescence PL) of Macromolecules with Conjugated Luminescent Markers... 

The results of the theoretical analysis in Sect. 1.2 show that in the study of relaxation processes in solutions of polymers containing luminescent markers (LM) much information is provided by the dependence of the reciprocal value of the polarization of luminescent light of the polymer solution, 1/p, on the viscosity of the solvent tj, 1/p =/(T/t ), measured at constant temperature T. Theoretical analysis of Eq. (1.2.10) shows that for macromolecules in solution in which all the relaxation processes occur at times Tj >Tf (t/ is the lifetime of luminescence) the following equation is valid for the average time r i (see Sect. 1.2) (Eq. 2.1) 1... 

Table 2. Relaxation times for conjugated polystyrene with various luminescent markers in toluene at 25 °C and values of — and (Symbols for types of LM as in Table 1) 6 0... 

Methods for the Preparation of Polymers with Covalently Attached Luminescent Markers of the Anthracene Structure... 

In general, the most comprehensive and accurate information concerning various relaxation processes typical of a given polymer and determining its characteristic IMM can be obtained by studyii polymers that contain liuninescent grou (luminescent markers, LM or reporters ) purposely covalently bonded to definite parts of the macromolecules. Usually, the LM content in the polymer does not exceed 0.1 mol% (i.e., 1 LM per 1000 units of the polymer of the main structure). An increase in the LM content can obscure the properties of the macromolecule. 

The methods based on reactions with the participation of macromolecules allow luminescent markers to be bonded to polymers and copolymers of the required composition, stereoregularity, molecular weight and molecular weight distribution, to samples of industrial polymers and to natural polymers. 

Methods for the Preparation of Brandied and Cros Linked Polymers with Luminescent Markers... 

The investi tion of the IMM of polymers of various classes by PZ, using anthracene-containing luminescent markers of similar stmctures, mainly 9-anthrjdmethyloxycarbonyl groups, allows conclusions to be drawn on influence of the substituents (their position, stmcture, and length) on the IMM of the polymer. 

The changes in IMM during the conformational helix-coil transformation in synthetic polypeptides have also been studied by PL The polymer used was poly(glutamic acid) (PGA) with anthracene-containing luminescent markers in the side chains (one marker per 1000 monomer units). The structure and the position of the marker are ... 

Block copolymers are an example of multicomponent polymer systems for which the problem of separate investigation of each component (block) of the copolymer is of particular interest. The PL method permits a successive separation of each block of the copolymer for the investigation of the IMM of the latter using luminescent markers . The PL method was applied to the study of the three-block copolymers of the ABA and BAB types where A and B are PMMA and polystyrene(PS)blocks. 

Table 13. Relaxation times characterizing the intramolecular mobility of the polymer chain, for the homopolymer and the block of the corresponding chemical structure and molecular weight M in three-block copolymers (PMMA-PS-PMMA) and (PS-PMMA-PS) at 25 °C ij,ed 0.38 cP. a) ratMA, b) PS. The polymer concentration in solution is 0.005% the component under investigation with a luminescent marker is denoted by ( )...

The rotation of the oscillator in a luminescent marker inserted into the polymer chain is always accompanied by a complex translational and rotational motion of chain segments adjoining it. The main task of the theory is to take into account the polymer effects proper in PL. This problem has been considered by several authors including the authors of this review. 

Thus, in the investigation of polarized luminescence of poly(methyl methacrylate) with a luminescent marker in the main chain it has been established that relaxation times r , are proportional to the solvent viscosity at a given temperature T ... 

Table 21. Parameters of the intramolecular mobility for high-frequency (rh.f. r/) and low-frequency (t Tf) relaxation processes in the main chain and in side chains of PMMA labeled with luminescent markers of different structure... 

The authors are greatly indebted to their colleagues and coworkers who helped in carrying out the synthesis of polymers with luminescent markers, the experiments and the theoretical calculations and in solving the problems discussed in this work. 

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