PHOTONIC-NEUROSURGERY LAB

Difato Francesco

Neuroscience research has recently taken advantage of optical approaches to record, modulate and manipulate the physiological activity of neurons. Studies on the nature of light-matter interactions have paved the way for emerging fields in biophysics and neuroscience, while advances in optical systems have provided minimally invasive approaches for studying the structure and function of living cells. Precise engineering of light-matter interactions allows contact-free manipulation of biological samples, such as the use of optical tweezers and laser dissector for precise and reproducible “optical surgery”. At the same time, molecular engineering has provided a new generation of optical probes to detect and modulate the activity of living cells.

My work has focused on the development of optical systems for the precise and controlled spatio-temporal manipulation of biological samples, and on the integration of optical setups with electrophysiological recording devices to study the central nervous system at various levels of complexity.

UOPTYoungaward  Taylor

  The Koh Young Best Paper Award 2012

      

Integration of Optical Manipulation and Electrophysiological Tools to Modulate and Record Activity in Neural Networks.  F. Difato, L. Schibalsky, F. Benfenati, and A. Blau. International Journal of Optomechatronics, 2011, 5(3), 191-216.

Corresponding Author: Difato F.

Photonic-neurosurgery lab @ JOVE

click on the image below to watch the published video article

JoVE

Articles tagged with: Micro electrode array

Electrophysiology

on Sunday, 18 March 2012. Posted in Home

Cultured neural networks represent a useful model in between single neurons and brain tissue for studying neural development, coding, pathology and regeneration. Neurons functionally reshape their interconnectivity not only in response to incoming activity from other cells, but also to external stimuli and changes of  environmental conditions (Muotri and Gage. 2006). Thus, studying cell physiology, cell motility and interconnectivity by interacting with cells or their organelles and controlling the intercellular organization and enviroment.
Complementary optical technologies such as optical tweezers (OTs) and laser microdissectors (LMDs) are among the most versatile tools for performing such manipulation experiments with high  spatio-temporal resolution under sterile conditions.
In contrast to most commercial OTs and LMDs, which are installed on inverted microscopes, the setup is mounted on an upright microscope. Nevertheless, both inverted and non-inverted optical pathways are optically accessible. This configuration allows the placing of specimen on transparent and non-transparent substrates alike without affecting the overall performance of the optical setup. The system is configured to work in combination with experimental techniques such as multichannel microelectrode array recording, patch clamp electrophysiology, and fluorescence imaging.

Laser Dissection

on Sunday, 18 March 2012. Posted in Home

By depositing a high instant energy in a small focal volume, the probability for multi-photon absorption, and the occurrence of other nonlinear optical effects is increased. Such localized energy deposition may serve for three-dimensionally confined sample ablation (Berns 1981). Using sub-nanosecond pulsed UV laser light instead, the average power at the sample required for optical dissection can be further reduced while, sharply confining the photo-damage to the focal volume. The laser dissector based on a sub-nanosecond pulsed UV-A source, permit to perform three dimensionally confined ablation just like systems based on two-photon absorption processes. However, it has the advantage of delivering extremely low average power (few µW) to the sample, thereby minimizing undesirable thermal effects.By laser dissection and concurrent calcium imaging it is possible to estimate the extracellular solution influx in to the dissected neurite.

By depositing a high instant energy in a small focal volume, the probability for multi-photon absorption, and the occurrence of other nonlinear optical effects is increased (A.Diaspro. 2002).  Such localized energy deposition may serve for three-dimensionally confined sample ablation (Berns et al. 1981; Sacconi et al. 2006).

Using sub-nanosecond pulsed UV laser light instead, the average power at the sample required for optical dissection can be further reduced while, sharply confining the photo-damage to the focal volume (Colombelli et al. 2007).

Structured light

Force spectroscopy

Growth cone navigation

Electrophysiology

Laser Dissection

Axon Regeneration