*2.2.5 Molecularly imprinted polymers (MIPs)*

In order to attain analyte specificity, templated polymer matrix is being used by synthetic biorecognition elements that are known as MIPs. MIPs create artificial patterns of recognition between the polymer matrix and the bioanalyte. MIPs are made to enclose the target bioanalyte. The choice of the target bioanalyte, crosslinker, functional monomer, and solvent affects tunability. Thus, biochemical identification of a particular biorecognition element-bioanalyte pairing is not necessary [6].

#### **2.3 Transducer**

Transducer is basically an energy transformer device, that is, it transforms one form of the energy into another. In a biosensor, it quantifies the signal by converting biorecognition activity. Such a technique for converting the energy is referred to as signalization. As an illustration, electrical or optical signals produced by transducers are normally proportional to the interactions' quantity between the bioreceptor and the analyte.

The five main classes of transducers in biosensors are magnetometric, thermometric, electrochemical, piezoelectric, and optical. These transducers are influenced by the material used, sensor features, and signal conversion technique. Materials can be classified as inorganic, organic, conductor, insulator, semiconductor, or biological. The device's design also significantly impacts the specifications. The transducer mechanism categorizes biosensors such as electrochemical biosensors. The market offers a wide range of transducing mechanisms for wearable biosensors, with user uptake and accuracy being crucial for developing user-friendly and sustainable technologies. Transducing mechanisms must be built to transform biosensing technology into wearable gadgets [3, 7].

#### **2.4 Electronics**

The transducer output signal is directed to the electronics section. Such a signal is analog, which is then transformed into a digital signal by a dedicated electronics circuit. This digital signal is subsequently measured based on its magnitude.

Flexible biosensors have become more common due to advancements in artificial intelligence, human-machine interfaces, and prosthetic skin. These systems consist of a sensor array, low-noise amplifier, analog-to-digital conversion (ADC), digital signal processing (DSP), and wireless transmitter. Integrated circuit development has been influenced by the need for low-noise and low-power sensing signal processing. Sigmadelta and successive approximation register (SAR) ADCs have performance limitations due to comparator and quantization noise. A more quantized capacitive DAC


### **Table 1.**

*Output signals' shape/mode of biosensors [9].*

(CDAC) with a greater effective number of bits (ENOBs) is needed, expanding the core size and increasing power consumption [3, 8].
