Hi. I hope you wish to know what preparations you need to be ready for M. Sc. Biotechnology. Well in that case lets go subject wise.

Genetics and Molecular Biology : Be thourough with Mendelian genetics, nucleic Acids, protein synthesis, genetic code, gene cloning and types of mutations and disorders. Go through techniques like molecular cloning, Nucleic acid extraction from different sources, DNA microarray, gene transfer processes like transformation,conjugation and transduction. Study different types of electrophoresis, functions enzymes, etc.

Be clear with the basic concepts and definitions of terms such as genes, chromosomes, alleles, and chromatin. You may refer Snustad and Simmon's Principles of genetics or Genetics by Strickberger, T. A. Brown, etc.

Biochemistry : Brush up the basic structures of biomolecules and revise carbohydrate metabolism, lipid metabolism pathways. Other than these, be thourough with principles and applications of techniques and instruments like different types of chromatography, colorimetry, Mass spectrometry, spectrophotometer, etc.

For biochemistry, Lehninger is one of the best books and would highly recommend it. However, if you wish to start with the basics and would like to have something simpler then you may refer Biochemistry by Satyanarayan. But i wouldnt recommend it for a long term purpose. For biochemical techniques and instrumentation you can refer Wilson and Walker's Principles and techniques of biochemistry and molecular biology.

Immunology : You should be clear with types of immunity, immune system and cells associated with it, antigen, antibodies - classes and sub classes,production of different types of antibodies and vaccines, activation, differentiation and maturation of T and B cells. Types of T cells, complement pathway (not necessary) and NK cells.

Study the basic principles, procedures and application of techniques like ELISA, RIA, Coomb's test, Immunodiffusion and reporter assays.

For immunology I would highly recommend Kuby's.

Cell & Developmental Biology : Revise cell and its types, Functions of cell components, cell cycle, cell division, development of animals and plants. You must also have knowledge about plant and animal tissue culture techniques, fertilization and reproduction as well as cell based assays.

I'd suggest you to read Cell and molecular biology by Gerald Karp.

Microbiology : Start from the basics - categories of organisms, staining, and you can study different microscopes, their principle, working and application. Also, you can revise industrial microlobiology - production of alcohol, wine , cheese, vinegar, butter and other food products. Make sure you remeber the enzymes and the specific temperatures at which the processes are carried out.

Pelczar is the most basic book which you can get but avoid using it much as its not even referred at B.Sc. level much. Prescott and Albert's are better and gives a way more exhaustive coverage of topics.

IPR, Bioinformatics and Biostatistics are other subjects that you may prepare for, however, the above mentioned ones form the backbone of biotechnology and a sincere preparation should suffice.

Hope this helps.