Investigation of Cellulose-Based Materials Applied in Life Sciences Using Laser Light Scattering Methods

Abstract

This review emphasizes the practical importance of laser light scattering methods for characterizing cellulose and its derivatives. The physicochemical parameters like molecular weights, the radius of gyration, hydrodynamic radius, and conformation will be considered when the reproducibility of polymer behavior in solution is necessary for the subsequent optimization of the property profile of a designed product. Since there are various sources of cellulose, and the methods of cellulose extraction and chemical modification have variable yields, materials with variable molecular weights, and size polydispersity will often result. Later, the molecular masses will influence other physicochemical properties of cellulosic materials, both in solution and solid state. Consequently, the most rigorous determination of these quantities is imperative. In this regard, the following are presented and discussed in this review: the theoretical foundations of the light scattering phenomenon, the evolution of the specific instrumentation and detectors, the development of the detector-coupling techniques which include a light scattering detector, and finally, the importance of the specific parameters of polymers in solution, resulting from the data analysis of light scattering signals. All these aspects are summarized according to the chemical classification of the materials: celluloses, esters of cellulose, co-esters of cellulose, alkyl esters of cellulose, ethers of cellulose, and other heterogeneous cellulose derivatives with applications in life sciences.

Keywords: cellulose-based materials; conformation; laser light scattering; molecular weight distributions; particle size distributions.

Figure 1

Graphical representation of Zimm equation for limit cases: (a) c = 0 and (b) θ = 0 (adapted from [24]).

Figure 2

Zimm plot for a polymer with high molecular mass [26].

Figure 3

Fluctuations of light intensities determined by the random motion of particles in solution.

Figure 4

Experimental setup of MALLS experiments in batch mode with scintillation vial.

Figure 5

Intensity distributions obtained by means of DLS for a polydisperse sample (A) and a monodisperse sample (B) [42].

Figure 6

Configuration of a chromatographic system in SEC-MALLS-RI detection [26].