This is one of the most intriguing new scientific topics to emerge in the time: quantum biocomputing or quantum-DNA computing. It is difficult to scale quantum-DNA computers at this point in time, even if they were possible. The purpose of this theme is to build quantum-DNA processors, memory devices, and other devices, all of which are based on this technology. The quantum-DNA sequential circuit was one of ten chapters devoted to circuits in this section. Quantum-DNA fundamental gates AND, OR, and NOT are used in this circuit’s functionality. This section goes into great details on the various aspects of the general design, construction, heat measurement, and operational time calculation. Large-scale quantum-DNA computing has a number of technical challenges to overcome. Computer architecture must comply with specific geometrical limitations in order to ensure smooth functioning. To put it another way, it’s an attempt to entirely demolish a barrier to quantum-DNA computing.