Integrated photonic biosensors are revolutionizing lab-on-a-chip technologies by providing highly sensitive, miniaturized, and label-free detection solutions for a wide range of biological and chemical targets. This review explores the foundational principles behind their operation, including the use of resonant photonic structures such as microring and whispering gallery mode resonators, as well as interferometric and photonic crystal-based designs. Special focus is given to the design strategies that optimize light–matter interaction, enhance sensitivity, and enable multiplexed detection. We detail state-of-the-art fabrication approaches compatible with complementary metal-oxide-semiconductor processes, including the use of silicon, silicon nitride, and hybrid material platforms, which facilitate scalable production and seamless integration with microfluidic systems. Recent advancements are highlighted, including the implementation of optofluidic photonic crystal cavities, cascaded microring arrays with subwavelength gratings, and on-chip detector arrays capable of parallel biosensing. These innovations have achieved exceptional performance, with detection limits reaching the parts-per-billion level and real-time operation across various applications such as clinical diagnostics, environmental surveillance, and food quality assessment. Although challenges persist in handling complex biological samples and achieving consistent large-scale fabrication, the emergence of novel materials, advanced nanofabrication methods, and artificial intelligence-driven data analysis is accelerating the development of next-generation photonic biosensing platforms. These technologies are poised to deliver powerful, accessible, and cost-effective diagnostic tools for practical deployment across diverse settings.

Micropipette aspiration (MPA) is an essential tool in mechanobiology; however, its potential is far from fully exploited. The traditional MPA technique has limited temporal and spatial resolution and requires extensive post processing to obtain the mechanical fingerprints of samples. Here, we develop a MPA system that measures pressure and displacement in real time with sub-nanometer resolution thanks to an interferometric readout. This highly sensitive MPA system enables studying the nanoscale behavior of soft biomaterials under tension and their frequency-dependent viscoelastic response.

Arrayed waveguide gratings (AWGs) are key optical components of various new applications in telecommunication, astronomy, medical imaging, and spectroscopy. It is a very powerful integrated light‐dispersion technology with significant flexibility for tailoring its performance to the individual system needs of each application. There are several examples of custom AWG designs in the literature aiming for improved system performance. In this review, an overview of the available methods for improving the bandwidth, spectral resolution, and transmission function shape of AWGs is provided. The working principle as well as the advantages and disadvantages of each method are discussed.

Polarization beam splitters (PBSs) are central elements for polarization handling. Here, we present the design of an ultra-broadband, low-loss, and easy-to-fabricate PBS based on a silicon nitride asymmetrical directional coupler for polarization-sensitive optical coherence tomography systems. The phase difference between transverse electric and transverse magnetic modes is introduced by using straight waveguides with different widths and an offset between them. A bent waveguide is placed close to the end of the through port in order to increase the operating bandwidth (i.e., more than 220 nm with greater than 15 dB of extinction). The overall device length is only 400 µm.

Integrated photonic biosensors are quickly changing the game in lab-on-a-chip technologies. These tiny yet powerful devices enable rapid detection of biological and chemical substances without labels or complex processing and deliver high sensitivity in a compact form. In this review, we walk through the core principles behind how these sensors work, how they are designed, and how they are combined with microfluidic systems to create smart, efficient diagnostic platforms. We examine several sensing approaches including resonant photonic structures and interferometric techniques, each bringing its own strengths in terms of accuracy, responsiveness, and scalability. Particular attention is given to complementary metal-oxide semiconductor-compatible materials like silicon and silicon nitride, which play a crucial role in enabling the efficient, high-volume, and cost-effective production of these devices. We highlight recent advances like optofluidic photonic crystal cavities and integrated detector arrays, and their promising applications in healthcare, environmental monitoring, and food safety. While challenges remain, such as processing complex biological samples and ensuring consistent large-scale production, emerging materials, flexible electronics, and AI-driven data analysis are paving the way forward. Ultimately, integrated photonic biosensors are poised to lead to a new era of portable, affordable, and high-performance diagnostic tools for real-world use.

We present a new approach for the microrheological characterization of soft suspended bodies. We obtain results comparable to AFM based dynamic nanoindentation. We discuss viscoelastic and poroelastic contributions to material behavior.