The invention relates to apparatus for the detection of particles and for particle analysis. The apparatus comprises a sample holder comprising a base and a projection extending from the base. The base includes a contact region where, in use, the surface of a fluid sample may contact the projection. The surface of at least the contact region of the projection exhibits properties that allow the surface of the contact region to be substantially wetted by a fluid sample when the apparatus is in use so that the fluid sample forms a meniscus having its apex in contact with the contact region of the projection. The invention also relates to methods for using the apparatus.